EGU General Assembly 2024  

The transition to sustainable energy systems introduces a complex landscape, wherein geothermal energy and carbon dioxide storage (CCS) play critical roles. These activities target geological formations that are always faulted and fractured. As the focus intensifies on alternative energy systems for decarbonisation, understanding these faulted rocks in the subsurface gains great importance. Fault and fracture systems can act not only as conduits for fluid flow but they can also be zones of mechanical weakness that may respond dynamically to fluid pressure changes due to natural geological processes or anthropogenic activities, such as CCS or geothermal extraction. This dual role of fault and fracture systems as pathways for fluid flow and as potential triggers for mechanical failure makes their study a cornerstone of sustainable subsurface resource management. The challenge lies in accurately characterising the permeability of these systems and estimating their mechanical behaviour under changing stress conditions. This is vital for ensuring the integrity and efficacy of operations like CCS and geothermal energy extraction, where even slight variations in fluid pressure can have significant implications. For instance, experiences from the fluid injection experiment for an enhanced geothermal system in Basel, Switzerland, and the In Salah CCS pilot site in Algeria highlight how minor changes in pore fluid pressures (as little as 10 MPa) can induce leakage and/or seismic activities. We highlight selected case studies from both active and prospective CCS and geothermal sites (in Svalbard and Mid-Ethiopian Ridge, respectively). These examples illustrate methodologies in fault stability analysis and geomechanical characterization, shedding light on the relationship between fluid flow, stress alterations, and rock mechanics in faulted and fractured formations. By coupling empirical data with modelling techniques, we present strategies to mitigate risks and enhance the efficiency of subsurface decarbonisation efforts.

How to cite: Rizzo, R. E., Keir, D. B., Busch, A., Forbes Inskip, N., Healy, D., Gudbrandsson, S., De Siena, L., and Vannucchi, P.: Fault Lines to Frontlines: Geomechanical Challenges of Sustainable Energy Transition, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15525, https://doi.org/10.5194/egusphere-egu24-15525, 2024.

Water and energy are inextricably connected as water is needed for energy development and vice versa. This linkage is referred to as water-energy nexus, which highlights the need for integrated management and study of both resources. The nexus becomes even more complicated with climate change as both resources are greatly impacted by climate change. This study is aimed to assess the impact of climate change on water demand by thermoelectric power plants. The Integrated Environmental Control Model (IECM) and the Global Climate Model (GCM) are integrated to simulate water demand under future climate scenarios. The daily, monthly, and yearly water demand by selected thermoelectric power plants in Illinois are examined to explore the temporal patterns of climate change impact on water-energy nexus. Initial results showed that water use is more sensitive to shorter timescales. Compared with water withdrawal, water consumption is more sensitive to climate change.  This approach is also coupled with a hydrological model, specifically, a HSPF model, to assess the water supply risks to thermoelectric power plants in the future climate scenarios.

How to cite: Zhang, Z., Wang, Y., De La Guardia, L., and Dang, W.: Water supply risks for thermoelectric power plants considering climate change , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-79, https://doi.org/10.5194/egusphere-egu24-79, 2024.

Unprecedental and unplanned urban sprawl poses a substantial challenge for cities in developing nations, detrimentally impacting the environmental quality of the urban landscape. The key environmental factors affected by urbanization must be vigilantly monitored to ensure sustainable urban development. Consequently, it is imperative to have a sustainable framework for a comprehensive and critical assessment of the environmental parameters that are affected because of urbanization. The aim of this research is to assess the environmental quality of a developing city in India – Bhopal and to quantify the environmental damage. The environmental quality is compared at 5-year time steps from 2000 to 2020 keeping 2000 as the benchmark year. The study employs satellite-based remote sensing data to extract all the parameters that are considered. The biophysical indicators (BI), include Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST), Particulate Matter concentration (PM2.5) and actual Evapotranspiration (ETa), and the census-related parameters include the Population Density (PD) and Built-up Volume (BV). The research assesses the relation between these parameters, followed by the quantification of an Environmental Quality Index (EQI) for the years 2005, 2010, 2015 and 2020 to investigate the city's environmental quality. The city's environmental quality is then categorized based on the EQI values in each year. The results reveal that there is a poorer quality of environment where the BV and PD is high, and vegetation cover is low, which also results into higher LST. PM2.5 was higher in the traffic congestion zones, industrialisation areas and major roads. The comprehensive findings indicate pronounced environmental degradation in specific areas characterized by dense urbanization, heavy traffic, industrial zones, and major highways. This study sheds light on the adverse environmental impacts of unplanned urbanization, providing valuable insights for policymakers and urban designers to enhance the quality of urban development and promote sustainability. Additionally, the research proposes strategies and policy interventions for addressing industrial and vehicular pollutants, emphasizing the crucial role of urban greening in elevating the overall urban environment.

How to cite: Singh, S., Shukla, A., and Jain, K.: A remote-sensing-based assessment of a city's urban environmental quality, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1106, https://doi.org/10.5194/egusphere-egu24-1106, 2024.

In Korea, various development projects such as port construction, nearshore wind farms, tidal reclamation, and seawall construction have been taking place along the coast, however spatial information and vulnerability assessment methods for proper environmental impact assessment are lacking. In this study, we categorized four sectors (social environment, protected areas, habitats, and species) to create vulnerability maps on each that can be used for environmental impact assessment. The vulnerability map for the social environment includes spatial information on fisheries, aquaculture, coastal tourism, and port facilities, while the vulnerability map for protected areas is based on international protected areas, marine reserves, and environmental and fishery resource management areas. Habitat vulnerability map is based on data for tidal flats and wetlands, seagrass beds, stop-over sites of migratory birds, and marine protected species habitats. Finally, species vulnerability map was created spatial fish catches and marine bird tracking data. Vulnerability maps for each sector are based on the scores assigned to sector-specific indicators.

How to cite: Kim, T., Maeng, J., Kim, E., Kim, T., and Lee, M.: A Study on Vulnerability Maps for Marine Environmental impact Assessment, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1384, https://doi.org/10.5194/egusphere-egu24-1384, 2024.

Bifacial solar modules and solar trackers are experiencing worldwide rapid development, and they are proven to be effective in increase solar power generation. This study presents a comprehensive worldwide assessment on technical and economic potential of combination of mono or bifacial photovoltaic modules with different solar trackers based on a high-quality long-term solar radiation dataset and a physical model chain. Impact factors such as topography, land suitability, etc. were taken into consideration when evaluating electricity generation potential. Overall, bifacial photovoltaic modules can increase power generation and lower levelized tariffs globally. Solar trackers can increase the efficiency of PV panels, but reduce the total power generation due to lower land utilization. Fixed bifacial modules contributed the highest total global power generation of 2217 PWh and the lowest average global levelized cost of electricity of 3.6. The spatial distribution of the optimal PV module and solar tracker combination is also revealed by this study. Furthermore, there is a significant mismatch between energy generation and demand, despite the fact that total global electricity generation potential far exceeds total electricity demand. Countries with 70% of the total generation potential consume less than 20 % of the demand. Distributed PV may contribute to solving this problem. As for the environmental and ecological impact, the global carbon reduction and loss in ecosystems service values are 1205 million Mt and 3244 million dollars per year, respectively. The Sahara Desert and Western Asia, with high power generation potential and low ecological costs, serve to be hotspots for photovoltaic. This study providing guidance for selecting, sitting and deploying different solar modules combination, and emphasize the ecological and environmental impact of solar panels.

How to cite: Shao, C., Yang, K., and Zhang, X.: Global technical, economic and ecological performance of different solar photovoltaic modules , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1956, https://doi.org/10.5194/egusphere-egu24-1956, 2024.

With the green transition in Europe from fossil fuels to renewable energy, it will significantly change the demand for raw materials. The European Union’s new growth strategy focuses on sustainability. While doing so, the intent is to reduce the dependency on non-EU countries regarding the raw materials supply. Access to raw materials has been questioned by the European Commission for twenty years as it is foreseen as new “oil and gas”. The transition requires using carbon-free energy resources and electric vehicles which leads to a great need for raw materials that are used in the production of wind turbines, solar panels and batteries, etc. However, Europe is mostly dependent on non-EU countries which poses a risk of supply chain disruptions, as witnessed in the Covid-19 pandemic and the war in Ukraine.

In this study, silicon (Si) metal, one of the critical raw materials having high economic value, will be investigated in terms of its usage, substitution, supply, demand, and future strategies. Si metal is used in aluminum alloys, electronic, chemical, and photovoltaic applications. Green transition and autonomy in the mineral supply chain in Europe both require upscaling mining and supply from secondary materials/recycling of critical raw materials. However, there is almost no recycling of Si metal since it is mostly dispersive in metallic alloys and chemical applications. Thus, mining should be considered as the main activity for the security and sustainability of the Si metal supply chain. This implies that Europe will need to overcome several disadvantages such as no sufficient exploration of resources, public opposition to mining and complex permitting procedures, since it is not given the priority to produce their raw materials. Considering the disadvantages, it is estimated that the upscaling of the mining activities will take 10 to 15 years.

Today, China controls 76% of the Si metal global supply which increased by 10% since 2020 and USA shares 8 %, Brazil 7 % Norway 6 % of global production. Norway shares about 50% of the Si metal produced in Europe and there are high-purity quartz deposits distributed across the country. Furthermore, Norway possesses renewable and cheaper electricity, which is typically the most costly element in producing metals, in addition to its natural resources. The availability of affordable power will most likely become more crucial in the future as energy sources shift from hydrocarbons to green energy sources. Finland is assumed to have a high-quality reserve, while the exact quantities are unknown. In Greenland, although the purity is unknown, the reserves are thought to be substantial. Sweden is also known to have potential reserves of high-quality quartz. As a result, this study will elaborate on the potential leading role of northern countries in meeting Europe's Si metal needs in the path of green transition.

How to cite: Akyıldız, O.: The Importance of Silicon Metal on the Green Transition and the Role of Northern Countries in the Silicon Metal Market, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4042, https://doi.org/10.5194/egusphere-egu24-4042, 2024.

In the context of a circular economy, increasing the durability of existing infrastructure is of paramount importance. Roads are the lifelines of the modern economy, and it is imperative to increase their lifespan as part of sustainable growth. Most conventional roads are a mixture of rock aggregate and bitumen. The region where bitumen meets aggregate in any asphalt mix experiences a complex interaction between electrostatic, chemical, and mechanical forces resulting in the formation of an Interfacial Transition Zone (ITZ) (Zhu et al. 2017). More specifically, there is a complex behavior of materials that could result from three different types of interaction between the aggregates, fillers, and bitumen: i) physisorption ii) chemisorption iii) mechanical interlocking (Pasandín and Perez 2015).

The integrity of the ITZ is one of the crucial factors for the overall durability of any mixture containing aggregate and binding materials. Due to the complex interaction of different minerals, present in the rock aggregate, with the bituminous binder, this junction is considered a weak link that dictates the overall structural durability of the mixture (Zhu et al. 2021). Most of the studies concerning the ITZ are based on mechanical tests at the aggregate-bitumen contact and generally do not include mineralogical observations.

The present study focuses on the ITZ within laboratory-manufactured asphalt samples utilizing rock aggregate varieties typically used in surface courses in the Republic of Ireland. Structural and petrographic observations are made using a combination of digital microscopy and Raman spectroscopy. Early observations suggest that there is a strong control exerted by aggregate mineralogy on the formation of features within the ITZ, including the linear alignment of iron oxide particles in the bitumen. Iron-oxide particles could potentially create a zone of weakness in a stone-mix asphalt, especially where the key aggregate is greywacke.

References

• Zhu et al. 2017; Identification of interfacial transition zone in asphalt concrete based on nano-scale metrology techniques, Materials and Design. 129, 91-102.
• Pasadin and Perez, 2015; The influence of the mineral filler on the adhesion between aggregates and bitumen, International Journal of Adhesion and Adhesives.

How to cite: Chakraborty, T., Unitt, R., and Meere, P.: Investigation of the Interfacial Transition Zone (ITZ) in asphalt mastic and its effect on the integrity of the mix: A Raman hyperspectral approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4378, https://doi.org/10.5194/egusphere-egu24-4378, 2024.

The dissolution and diffusion process of hydrogen sulfide (H₂S) in aqueous solutions are critical in the formation of many metal deposits and the stability of H₂S hydrate also play an important role in natural gas exploitation and transportation due to the tendency of H₂S to form hydrate at low temperature and high pressure, which can lead to pipeline blockage. In this study, the solubility and diffusion coefficient of H₂S in water and brine as well as the stable conditions of H₂S hydrates have been determined using fused silica capillary cell, high pressure optical cell, high pressure reactor, and Raman spectrometers.The details are as follows: (1) H₂S solubility data in water were obtained at temperatures up to 573 K and pressures up to 100 MPa. These new data extend the predictable range of previous models. (2) The diffusion coefficients of H₂S in water at 0.1–2 MPa and 273.1–373.1 K and in four brine solutions (0.62, 1, 2, and 3 mol•kg⁻¹ NaCl) at 1 MPa and 273.1–373.1 K were determined. The results showed that the diffusion coefficient increased with the temperature and was inhibited by salinity. (3) The stability of H₂S hydrate in water and brine including NaCl, KCl, MgCl₂, NH₄Cl, Na₂SO₄ and K₂SO₄ at the temperature range from 273.4 to 298.8 K, pressure ranging from 1.13 to 21.90 bar, and salinity from 3.4-20.0 wt.% were investigated. The results showed that the inhibitory effect of six electrolytes on H₂S hydrate formation is in the order of MgCl₂ > NH₄Cl > NaCl > KCl > Na₂SO₄ = K₂SO₄.

How to cite: Jiang, L., Wu, C., Sun, J., and Lin, J.: Determination of the solubility, diffusion coefficient and hydrate stability of hydrogen sulfide in water and brine, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7342, https://doi.org/10.5194/egusphere-egu24-7342, 2024.

Energy storage is vital to buffer intermittency in power supplies comprised largely or wholly of variable sources (e.g. wind, solar) at large and small scale. Present technologies and those in development (e.g. electrochemical cells) have disadvantages (e.g. cost, resource use, chemical hazard) whilst the capacity required is extremely large and widely distributed. Storage is needed for burgeoning off-grid small-scale infrastructure such as sensor networks as well as larger scale power sources. To address challenges with current technologies we demonstrate the ability of the pedosphere to store electrical energy and act as a natural, biogeochemical battery. The pedosphere, consisting of porous geomaterials such as soil and sediment, is an extensive potential energy repository covering much of the Earth and underpins most infrastructure or situations where power is generated or required. This pre-existing capacity has the potential to simplify energy storage and the installation and management of power generating or consuming infrastructure.

In this study the concept of such ‘geo-batteries’ is demonstrated. Controlled microbial synthesis of simple organic molecules in natural porous media (estuarine sediment) is shown, with this organic matter acting as an accessible form of energy storage. When combined with the employment of a microbial fuel cell to extract this energy electrically through degradation of the organic molecules, a battery is formed, with external control over energy input and output through switching of charging and discharging cycles.

This project received funding from the UK Engineering and Physical Sciences Research Council, grant no. EP/X018865/1.

How to cite: Harbottle, M., Smith, H., Kennedy, J., Sapsford, D., Cleall, P., Weightman, A., and Carlos, U.-L.: Microbially mediated energy storage in the pedosphere , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9593, https://doi.org/10.5194/egusphere-egu24-9593, 2024.

As global efforts towards achieving net-zero targets continue to grow, countries experiencing a surge in demand for renewable energy infrastructure may encounter competition due to uneven production capacities. Currently, European renewable energy infrastructure depends on limited suppliers and technologies, which have the potential to be diversified and robustified. This work aims to explore the potential supply chain transition of net-zero European renewable energy infrastructure and evaluate it in terms of environmental impacts, policy robustness, and economic costs. Based on results from scenario analysis, we find that the trade-offs always exist, i.e., sustainability, reliability, and affordability cannot be simultaneously achieved in a single scenario. Furthermore, the study emphasizes the close interaction of European renewable energy infrastructure with global capacity and market, indicating the need for a holistic approach in addressing the challenges of achieving a sustainable and resilient energy future.

How to cite: Cui, C.: Sustainable, Reliable, or Affordable: The Future European Renewable Energy Infrastructure, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12941, https://doi.org/10.5194/egusphere-egu24-12941, 2024.

Precisely determining lithology and petrophysical parameters, including core-calibrated porosity and water saturation, is crucial for reservoir characterization. The traditional method of manually interpreting well-log data is not only time-consuming but also prone to human errors. To address these challenges in identifying lithology and estimating petrophysical parameters in Athabasca Oil Sands region, this study introduces a novel solution using the AutoRegressive Vision Transformer (ARViT) model for accurate prediction. ARViT improves upon the ViT framework by integrating sequential dependencies into its output. The self-attention mechanism and auto-regression are key features that enable ARViT to systematically process data, capturing detailed spatial dependencies in well-log data. This empowers the model to discern subtle spatial and temporal relationships among various geophysical measurements. In essence, ARViT's incorporation of sequential information through its auto-regression mechanism on top of ViT enhances its ability to comprehensively model complex relationships within well-log data. In this study, a multitask learning approach is embraced to enhance the model's interpretability and efficiency. This methodology involves optimizing the model's performance across multiple tasks simultaneously. By doing so, the model gains a broader understanding of diverse tasks and benefits from shared knowledge and features across these tasks. This collaborative optimization contributes to a more robust and versatile model, ultimately improving its overall perflormance and interpretability. To evaluate the effectiveness of the ARViT model, we conducted a comprehensive series of experiments and comparative analyses, contrasting its performance with conventional artificial neural networks (ANN), Long Short-Term Memory (LSTM), and ViT models. Furthermore, to illustrate the versatility of ARViT, we apply Low-Rank Adaptation (LoRA) to a different, smaller dataset of well-log, showcasing its ability to adapt effectively to various geological contexts. LoRA becomes particularly crucial in this context, as it not only enhances the model's adaptability but also plays a vital role in reducing the number of trainable parameters. This reduction not only contributes to computational efficiency but is essential for preventing overfitting and ensuring optimal performance across different datasets. Our findings demonstrate the consistent superiority of ARViT over ANN, LSTM, and ViT in accurately estimating lithological and petrophysical parameters. This is highlighted by ARViT's remarkable Lithological Accuracy of 96.51%, surpassing the baseline ANN's 73.18%, LSTM's 89.80%, and ViT's 93.23%. The substantial reduction in Mean Squared Error (MSE) for porosity, decreasing from 0.0007 (ANN) to 0.0004 (ARViT), and water saturation, decreasing from 0.022 (ANN) to 0.005 (ARViT), further emphasizes ARViT's exceptional performance in providing precise and reliable predictions across various metrics. The application of LoRA yields notable enhancements in ARViT's performance metrics. Specifically, in terms of Lithology Accuracy, ARViT-LoRA showcases a significant improvement, soaring from 88.74% (ARViT-Scratch) to an impressive 97.22%. Additionally, the implementation of LoRA resulted in a significant reduction of GPU consumption by 25%. While lithology prediction has been a well-explored field, ARViT distinguishes itself through its exclusive combination of features, encompassing a self-attention mechanism, auto-regressive nature, and multitask approach, coupled with effective fine-tuning using LoRA. This unique combination positions ARViT as a valuable tool for addressing intricate challenges of lithology prediction and petrophysical parameter estimation.

How to cite: Nasim, M. Q., Singha Roy, P. N., and Mitra, A.: Joint Optimization of Lithology and Petrophysical Parameters in Athabasca Oil Sands Using Self-Attention Mechanism, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14109, https://doi.org/10.5194/egusphere-egu24-14109, 2024.

Delivering the goals of the Paris Agreement, including limiting global temperature rise to no more than 1.5°C requires the setting and implementation of ambitious yet viable Nationally Determined Contributions, or NDCs. Article 4 of the Paris Agreement establishes a responsibility on each party to ‘prepare, communicate and maintain’ successive NDCs, each more ambitious than the last. Parties are then encouraged to work at a domestic level to achieve their NDC objectives.

Based on an analysis of NDCs from eastern and northern Africa (including Ethiopia, Eritrea, Kenya, Malawi, Rwanda, Tanzania, Somalia, Sudan, and Uganda) here we outline steps that would (i) strengthen opportunities for scientific input in the development of NDCs, ensuring that the mitigation and adaptation pledges included are both comprehensive and scientifically feasible, and (ii) improve aligned implementation strategies, ensuring coherence with higher education and research and innovation, and a cross-governmental approach to addressing climate change.

A lack of engagement with appropriate expertise when developing NDCs may result in pledges that are not viable and/or the omission of feasible and impactful options. A lack of appropriate implementation planning, and policy coherence, may result in a skills shortage that hinders implementation of actions set out in NDCs and therefore the ability to deliver the mitigation and adaptation ambitions of the Paris Agreement. Collectively, the steps we propose would strengthen the NDC process, while also supporting global ambitions to improve education for sustainable development (Sustainable Development Goal 4.7), employment opportunities (Sustainable Development Goal 8.5, 8.6), and research capacity (Sustainable Development Goal 9.5).

How to cite: Gill, J., Daniels, K., Maidment, D., Salih, M., and Blythe, L.: Enhancing the Ambition and Technical Feasibility of Delivering Nationally Determined Contributions to the Paris Agreement, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17869, https://doi.org/10.5194/egusphere-egu24-17869, 2024.

Constructed wetlands (CW) have emerged as sustainable and eco-friendly solutions for mitigating the impact of nutrient pollution in water bodies. Nutrient pollution, primarily caused by excess nitrogen and phosphorus, poses significant threats to aquatic ecosystems, leading to issues such as algal blooms, oxygen depletion, and impaired water quality. In response to these challenges, constructed wetlands have gained prominence as innovative systems capable of efficiently removing nutrients from wastewater and stormwater. These engineered ecosystems mimic the natural processes of wetlands to effectively treat wastewater. Among the key factors influencing the efficiency of nutrient removal, the choice of plantation method in CW stands out as a crucial aspect that demands closer scrutiny. As such, understanding the impact of different plantation methods on nutrient removal becomes paramount for optimizing the performance of constructed wetlands. This study focuses on elucidating the role of diverse vegetation strategies in enhancing the performance of these systems, with particular emphasis on nutrient uptake and transformation processes. Through a comprehensive review of existing literature, this research aims to identify and analyze the impact of various plantation techniques on nutrient removal efficiency. Factors such as plant species selection, plantation type i.e., single plant in a system (monoculture) or multiple vegetation in the system (polyculture) are examined to ascertain their influence on nitrogen and phosphorus removal rates. Polyculture improved TN and TP removal in horizontal subsurface CW by around 5%. However, a very high increment in treatment efficiency of both TN and TP was observed for vertical subsurface CW being more than 20%. Polyculture provided synergistic effect of various plant and microbial species for higher removal of nutrients from wastewater. Ultimately, the research aims to delineate the effect of plantation on performance of different CW in terms of mitigation of nutrient pollution in wastewater.

How to cite: Jain, M., Sharma, B., Pilla, S. K., Ghosal, P. S., and Gupta, A. K.: Nutrient removal in constructed wetlands: Especial emphasis on type of plantation method, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17873, https://doi.org/10.5194/egusphere-egu24-17873, 2024.

Geosystem services as a concept allow for understanding the benefits that are gained from abiotic processes and structures that contribute to human welfare. These services are obtained from the diversity of the geosystem (of which the subsurface is a part) are often overlooked and undervalued. Intense anthropogenic utilization of these finite services, emphasizes the need for pre-emptive management of the subsurface. While the concept of geosystem services allows for capturing the plurality of the subsurface (in terms of different functions and services), it is often under-emphasized in subsurface management. The objective of this paper is to systematically review the existing approaches for the management of geosystem services in literature and contextualize the principle of sustainable scale in terms of a conceptual scheme for the subsurface. The systematic review's findings reveal a lack of comprehensive discussions on the management of geosystem services. Instead, the current discourse revolves around identifying various components that require management and emphasizing the necessity for active management. Although the articles propose recommendations for the management of geosystem services, they lack a set of operationalized principles that can be used by policymakers. To establish a conceptual scheme for the sustainable management of the services obtained from the services, the principle of sustainable scale as found in the literature of Ecological Economics was contextualized. The proposed conceptual scheme resulted in the following key aspects: (a) connects the subsurface characteristics (e.g. replenishment rates, different functions) and the nature of benefits (economic, environmental, and social) (b) provides the conceptual basis for defining the scale of subsurface utilization based on the type of service and its regeneration rate.

How to cite: Eswaran, A., Compernolle, T., and Piessens, K.: Sustainable Scale for Geosystem Services Use: Addressing the missing link in subsurface management, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19931, https://doi.org/10.5194/egusphere-egu24-19931, 2024.

Wastewater treatment plants (WWTPs) are critical environmental solutions for sanitation management in many cities and municipalities. The construction of these facilities uses cementitious materials (e.g., concretes) due to their low cost, high strength and excellent watertightness properties. However, the long-term performance of these materials in WWTPs is affected by deterioration influenced by the formation of new (secondary) cement minerals. These secondary minerals are formed as a result of biogeochemical interactions between cementitious materials and wastewater microbial communities. The literature shows a lack of consensus on the mechanisms involved in the biogeochemical mechanism of sewage and cementitious materials in WWTP facilities. As a result, many civil and water engineers are unaware of its adverse effects on the sustainability of WWTP facilities, and as a consequence, the operation of many WWTP facilities costs billions of dollars in repair and maintenance due to concrete failure. This study studies the possible processes of biogeochemical interactions between sewage and cementitious materials in WWTPs and their subsequent mineral alteration and formation.

An in-situ experiment exposed 48 cement specimens of ordinary Portland cement and calcium sulfoaluminate cement to the sewage pumping station and sand-trap structures. The research involves: (1) geochemical analysis (SEM and XRD) to study the change of cement materials, (2) engineering analysis to study their mechanical change and (3) microbiological investigations to explore the microbial communities involved in the biogeochemical interaction.

The preliminary results of the study: (a) change of color from light grey to a mixture of yellow and brown for cement pastes exposed in the sewage pumping station, whereas the samples from the sand-trap maintained their original grey color. (b) the appearance of secondary minerals such as gypsum (CaSO₄.2H₂O), ettringite (Ca₆Al₂(OH)₁₂(SO₄)₃·26H₂O), and thaumasite (Ca₃Si(OH)₆ (CO₃) (SO₄)₁₂.H₂O) which are characterized as expansive process causing several cracks in the concrete structures. (c) the main mechanism for the formation of these sulfur-related minerals (i.e., gypsum, ettringite, and thaumasite) involves sulfide adsorption and its subsequent oxidation to form biogenic H₂SO₄ which eventually attack the cement alkaline mineral phases such as portlandite (Ca(OH)₂ and calcium silicate hydrate (C-S-H). Another biogeochemical mechanism for sewage-cement interaction observed in this work was the carbonation process, which resulted in the formation of calcite mineral in hydrated cement.

How to cite: Kashaija, N., Gável, V., Gergely, K., Szabó, C., Tóth, E., and Szabó-Krausz, Z.: Effects of biogeochemical interactions between cementitious materials and sewage on the durability of wastewater treatment plant facilities, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20300, https://doi.org/10.5194/egusphere-egu24-20300, 2024.

Coal power transition always maintains a high complexity as the heterogeneities of characteristics such as technical attribute, economic lock-in, and environmental and health impact. Here, we explored the cost-effectiveness uncertainty brought by policy implementation disturbance of different phaseout and new-built strategies (i.e., the disruption of phaseout priority) of coal power based on a developed unit-level uncertainty assessment framework, and revealed the opportunity and risk of coal transition decision by employing preference analysis. We found that, the uncertainty of policy implementation might lead to potential delays in yielding the initial positive annual net benefits. For example, a delay of 6 years might occur when the prior phaseout practice is implemented. A certain level of risk remains in the implementation of the phaseout policy, as not all strategies can guarantee the achievement of positive cumulative net benefits from 2018-2060. Since the unit-level heterogeneities shape diverse orientation of decision making, the decision-making preferences would significantly alter the selection of coal transition strategy. While the uncertainty of policy implementation might lead to missed opportunities in identifying optimal strategy. Our results highlight the importance of minimizing the policy implementation disturbance, which helps mitigate the risk of negative benefits and strengthen the practicality of phaseout decision.

How to cite: Yan, X. and Tong, D.: Cost-effectiveness uncertainty may bias the decision of coal power transition in China, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1232, https://doi.org/10.5194/egusphere-egu24-1232, 2024.

Solar parks are a rapidly expanding novel land use primarily to produce renewable energy. However, the aim is to make them multifunctional, and limit negative impacts on soils or even improve soil quality. Solar panels change the microclimate and cause shading below the panels, influencing plant growth and carbon and water inputs to the soil, with potential cascading effects on the soil biota. This research aimed to test the effect of solar panels on earthworm and nematode communities in 12 solar parks with contrasting designs across the Netherlands. Earthworm abundance and diversity, plant biomass and nematode abundance were measured between (gap) and below the solar panels. Nematode abundance was also measured at the highest and lowest edges of the panels. Plant biomass, nematode abundance and earthworm abundance were all significantly lower below the solar panels compared to in the gap between the panels. Nematode abundance at the highest and lowest edges showed intermediate numbers compared to the gap and below the panels. These results show that solar parks have a large impact on the soil biota and stress the need for guidelines for ecologically sound solar park designs to prevent soil damage.

How to cite: Scholten, L., De Deyn, G., and de Goede, R.: Solar park impacts on plant biomass and earthworm and nematode communities, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1833, https://doi.org/10.5194/egusphere-egu24-1833, 2024.

Green Riyadh project is one of the most ambitious urban forestation projects in the world. It is one of Riyadh’s four megaprojects launched on 19 March 2019. The project will be a milestone that contributes to fulfilling a key goal of the Saudi Vision 2030 to promote Riyadh’s position among the world’s top livable cities.

The Green Riyadh project will contribute to increasing the per capita share of green space, and raise the total green spaces by planting trees around all city features and facilities as well as in all its provinces. All of the greenings will be watered by recycled water from an irrigation network. The greening initiative will lead to improved air quality and reduced temperatures in the city. As a consequence, this project will encourage Riyadh citizens to follow a healthy lifestyle which is part of the Kingdom’s Vision 2030.

Afforestation include planting 7.5 million trees across the capital, 3,330 neighborhood gardens, 43 parks, 6,000 schools, 2,000 car parking sites 1,670 public facilities, 390 healthcare facilities 64 universities and colleges, 16,400 kms of streets and roads, 1,100 kms green belts along utilities lines (power stations oil pipelines, etc.), and 272 kms valleys. About 72 native shade plant species compatible with Riyadh’s environment will be used for the project.

Project benefits include the reduce of ambient temperature by 2 Celsius degrees during summer season, reduce temperatures by 8-15 Celsius degrees in selected intensively afforested locations across the city improve the air quality by reducing CO2 concentration by 3-6%, reduce dust concentration in the air, reduce annual power consumption by 650 gigawatt/hour, through encouraging the principles of Green Building techniques that use green ceilings and walls, improve readiness for handling rainwater and minimize the flood hazards , encourage citizens of Riyadh to adopt a healthy lifestyle, preserve natural zones and improve the biological diversity , improve quality of life and promote Riyadh’s position among the world’s top liveable cities, yield about 18 billion Euro as ROI 2030 through less healthcare expenses, lower electricity consumption, higher real estate value, use of treated wastewater as a replacement for potable water for irrigation, and Improve urban landscape of Riyadh.

How to cite: AlHumidan, S.: Green Riyadh, Ambitious Urban Environmental Forestation Project, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2411, https://doi.org/10.5194/egusphere-egu24-2411, 2024.

Solar energy is the most rapidly growing renewable globally. However, ground-mounted solar panels have a high land requirement, leading to extensive, low-nature-value photovoltaic parks. This may be alleviated by considering ecological aspects during their planning, construction and mainetnance. The resulting ecovoltaic park can bring various benefits for the owners if ecosystem services related to the imporved ecological conditions are recognized and wisely utilized. A major step in developing ecovoltaic parks is the creation of a short but species-rich grassland ecosystem. There is little empirical evidence on how to achieve this; therefore, we set up an experimental sowing experiment in three formerly conventional photovoltaic parks located in the forest-steppe zone of Hungary. From the regional native grassland species pool, we selected short but competitive ones (two graminoids and 50 forbs that are often visited by pollinators), and sowed them in half of the parks (between panel rows) in October, 2022, while the other half was left as control. In 2023, we surveyed the vegetation of the sown and control parts of the parks and adjacent old-growth grasslands (as references), and found that total plant species richness and the species richness of grassland specialists increased compared to the control sites, but remained below the references. In contrast, the cumulative cover of grassland specialist species in the sown sites could reach the references. We also surveyed pollinator assemblages (hoverflies and wild bees), and found higher species richness and Shannon diversity in the sown parts then in the reference grasslands, while control parts of the parks showed intermediate values. This might have been caused by spillover from the sown parts, although flying pollinators might have also taken advantage of the permanent windshade among the panel rows of control parts, despite the low food supply compared to the reference grasslands. Our findings suggest a rapid improvement of plant and pollinator assemblages after sowing native seed mixtures in solar parks. The resulting high-nature-value grassland ecosystem can have many co-benefits for the owners, as (i) it requires lower management intensity due to the short vegetation, (ii) has the potential to offer high-quality forage for livestock or honey-bees, and (iii) lowers the widespread “not-in-my-backyard” syndrome of local inhabitants due to its attractive, flower-rich appearance.

How to cite: Tölgyesi, C., Magyar, B., Frei, K., Hábenczyus, A. A., Bátori, Z., and Gallé, R.: Introducing the first ecovoltaic parks of Hungary: a reconciliation between solar development and nature conservation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2933, https://doi.org/10.5194/egusphere-egu24-2933, 2024.

Residential sector contributes significantly to emissions of various air pollutants and adverse health impacts in rural China. One of the major activities leading to the emissions is space heating using solid fuels in rural households. Although cooking energy has switched rapidly towards clean one in the past several decades, solid fuels still dominate the heating activity in rural areas, primarily due to high cost of using electricity or natural gas. A recent government intervention in North China Plain to replace coal with clean energy for rural residential heating has resulted in great success. Here we show that the clean heating is feasible for a large rural population in entire heating zone at reasonable cost. Electricity is preferred over natural gas for cost, save, and energy security reasons. The scheme of promoting clean heating can be optimized based on population density. If per capita investment can reach 1,700 RMB, 75% of rural population in the heating zone can be covered, resulting in avoidance of 42,000 premature deaths associated with exposure to PM2.5 from solid fuels.

How to cite: Tao, S.: Cost and health benefits of clean heating in rural China, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3840, https://doi.org/10.5194/egusphere-egu24-3840, 2024.

The urban population is experiencing rapid growth, and it is estimated that around 90% of people will be living in cities by the year 2100. Given that urban areas are significant sources of greenhouse gas and pollutant emissions, and with the expectation that these urban areas will become even more densely populated, achieving sustainable urban living requires careful and well-informed urban planning for infrastructures capable of effectively mitigating these emissions. One commonly proposed approach to address this challenge is the implementation of urban green infrastructures, which are often regarded as net sinks for CO₂. However, due to the diverse and varied land use within urban areas, our ability to precisely isolate and quantify their overall impact on the city's carbon balance is limited.

Our research aims to overcome this limitation by testing two distinct frameworks. The first integrates remote observations with local measurements to determine the carbon balance of green infrastructures at the city level, ultimately producing a detailed CO₂ sequestration map of these infrastructures. The second utilizes satellite observations of solar-induced chlorophyll fluorescence, a signal emitted exclusively by vegetation, to estimate urban vegetation's city-wide carbon sequestration potential. Our findings demonstrate that these two frameworks provide valuable insights into the carbon sequestration capacity of green infrastructures.

The frameworks developed in this study offer a significant advancement in understanding the contribution of green infrastructures to the carbon budget of cities. This improved understanding can inform the planning of low carbon-emitting cities and aid in identifying green areas with limited—or even negative—net carbon uptake. Additionally, the results of this research may be instrumental for policymakers and city planners in developing more sustainable urban environments.

How to cite: Kira, O., Bamah, J., Muleta, A., and Bushner, S.: Remote sensing-based frameworks to quantify city-level carbon fluxes in urban green infrastructures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4551, https://doi.org/10.5194/egusphere-egu24-4551, 2024.

Food waste (FW) has a substantial environmental impact, contributing to 4.4 GtCO₂ eq annually, equivalent to approximately 8% of total anthropogenic greenhouse gas emissions based on carbon footprints. Indonesia ranks as the world's second-largest food waste producer, estimated to generate 300 kg of food waste per capita per year. However, there is a scarcity of studies assessing the electricity generation potential and economic feasibility of biogas-to-electricity projects in Indonesia. This paper presents the recovery of biogas from food waste for electricity generation, aiming to determine its economic and environmental benefits for Jakarta, Indonesia. The food waste generation potential in Jakarta was estimated from 2024 to 2043, and the theoretical methane yield was calculated using Buswell's equation. The economic feasibility of anaerobic digestion projects was analyzed using various methods, including total life cycle cost, net present value, investment payback period, levelized cost of energy, and internal rate of return. Environmental impact assessment included air pollution (SO₂, NOx, and PM₁₀) and greenhouse gas (CO₂ and CH₄) emissions reduction. Methane yield from anaerobic digestion was determined to range from 315.9 to 616.5 × 10⁶ m³/yr, with electricity generation potential between 721.5 and 1,407.9 Gigawatt-hours. Economic indicators demonstrated the viability of anaerobic digestion, with positive net present values. The net present value and levelized cost of energy for anaerobic digestion were $162.8 million and $0.095 per kilowatt-hour, respectively. Utilizing biogas from anaerobic digestion for electricity generation could displace 8.2 million tons of coal over the system's lifespan. This displacement would lead to reductions of 17.8 million tons of SO₂, 13.9 million tons of NOx, 1.7 million tons of PM₁₀, and 20.1 million tons of CO₂ compared to coal combustion.

Acknowledgments

This research was supported by Particulate Matter Management Specialized Graduate Program through the Korea Environmental Industry & Technology Institute (KEITI) funded by the Ministry of Environment (MOE).

How to cite: Park, J.-K., Jung, M.-J., Yun, H.-Y., and Wang, K.-H.: Electricity generation using biogas from food waste in Jakarta, Indonesia: Techno-economic and environmental impact analysis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4911, https://doi.org/10.5194/egusphere-egu24-4911, 2024.

An increasing amount of CO₂ emissions from the household sector of Iran led us to analyze the inequality and understand the possible driving forces behind the CO₂ emissions. The household sector in Iran contributes one of the largest sectors of CO₂ emissions. The study of inequality provides information to policy‐makers to point policies in the right direction. By considering the differences in the socio‐economic factors of provinces, the study aims to analyze the inequality in CO₂ emissions and different kinds of energy consumption, including oil, gas and electricity, for the household sector of Iran’s provinces between 2000 and 2019. Also, Household panel data of 28 provinces of Iran are employed by using both static and dynamic panel models for the years 2001 to 2019. This study investigates the relationship between CO₂ emissions and the efficient factors in three major groups including energy, climate, and household socio-economic factors. the Theil index and Kaya factor, as a simple and common method, were considered to evaluate the inequality in both CO₂ emissions and energy consumption, and determine the driving factor behind CO₂ emissions. According to the results, inequality in oil and natural gas consumption were increasing, electricity was almost constant; however, CO₂ emissions experienced a decreasing trend for the study period. The results of the Kaya factor indicate that the second factor, energy efficiency, with a 0.21 value was the main driving factor of inequalities in CO₂ emissions. The empirical result of the static method showed a positive dependence of household CO₂ emissions on Heating Degree Days (HDD), Cooling Degree Days (CDD), precipitation level, oil consumption, gas consumption, household income, size of household, and also building stocks. Also, removing the energy subsidy for fossil fuels due to substantial subsidy in fossil fuels in Iran or implementing a re-pricing energy policy can be a beneficial way to control carbon emissions from households within the provinces of the country.

Behnam Ata is funded by the Stipendium Hungaricum scholarship under the joint executive program between Hungary and Iran.

The study was elaborated under the research project TKP2021‐NKTA‐32 . 

How to cite: Ata, B., Pakrooh, P., and Pénzes, J.: Inequality and driving factors in regional level energy-related CO2 emissions at a residential sector of Iran, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5653, https://doi.org/10.5194/egusphere-egu24-5653, 2024.

The importance of accurate monitoring of carbon dioxide (CO₂) emissions from cities is underlined by the substantial urban contribution to global fossil fuel combustion. Typically, cities quantify emissions of CO₂ using inventories and also use these models to design appropriate local mitigation policies and measures. However, inventories of individual cities can be uncertain (lack of appropriate activity data and emission factors, uncertainties in spatial downscaling) and furthermore often do not include estimates for the sector Land Use, Land-use Change and Forestry (LULUCF). While the relative, total contribution of LULUCF to a city’s annual CO₂ balance may be assumed small, such an assumption should be verified. Furthermore, biogenic fluxes of photosynthesis and respiration may indeed be significant at higher temporal resolutions and omitting these fluxes can limit the conclusions drawn from comparisons of city CO₂ inventories with estimates based on atmospheric CO₂ observations.

The Vienna Urban Carbon Laboratory is currently investigating how monitoring of CO₂ emissions in Austria’s capital city can be supported by a range of atmospheric measurement methods, including a tall-tower, urban application of eddy covariance. Despite the focus on atmospheric observations, the project is also investigating the contribution of biogenic fluxes to Vienna’s net CO₂ budget. A LULUCF model of annual carbon stock changes has been developed following the IPCC guidelines using inter alia local forest inventory data and spatially-explicit data on land use and urban tree crown cover. Parrellel to this, work is underway to implement spatially- and temporally resolved simulations of vegetation CO₂ fluxes using semi-empirical models of photosynthesis and respiration. Ultimately, integrating these results (together with bottom-up estimates of human respiration) will provide a more meaningful comparison between the local CO₂ inventory with the fluxes derived from the eddy covariance measurements.

How to cite: Fasano, E., Schmid, C., Moldaschl, E., Mayer, M., Braun, S. K., Vuolo, F., Weiss, P., Schume, H., and Matthews, B.: Investigating the contribution of biogenic sinks and sources to Vienna’s CO2 budget using bottom-up modelling and tall-tower flux measurements, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5919, https://doi.org/10.5194/egusphere-egu24-5919, 2024.

Highly accurate land cover (LC) information with fine spatial resolution serves as the cornerstone for reliable environmental insights, strategic land management, and ecological conservation. Yet, existing public LC products with 1-30m resolution exhibit considerable inconsistencies, particularly within complex terrains and fragmented habitats such as hill and gully regions, leading to uncertainties in various applications. In this context, our study innovatively targeted China's hilly and gully regions to develop an enhanced 10m resolution LC map for 2020, termed CLC-HG. The methodological advancement lied in fusing multiple LC products through accuracy evaluation, spatial consistency verification, object-oriented classification, and random forest classification. The research involved: (1) Strategic zoning of hilly and gully regions into five areas, selecting one or two representative validation regions within each; (2) Leveraging high-resolution imagery and 20000 field verification points to derive a 1m resolution land use dataset for validation regions, named GFLUCC, with 1m resolution and 95% accuracy; (3) Comprehensive validation of seven land use products spatial consistency and accuracy based on GFLUCC; (4) Filtering of layers based on spatial consistency, retaining regions with high and medium consistency; (5) Utilizing object-oriented classification and random forest classification, a higher-accuracy LC dataset was generated to replace the layers that were removed in the spatial consistency process; (6) Successful creation of CLC-HG, mirroring the accurate land use patterns of 2020. Our findings elucidated: (i) The superiority of WorldCover 10m in LC classification, contrasting with other products' regional inaccuracies; (ii) The influences of terrain complexity and human activity on accuracy, highlighting the precision in uniform areas versus the inaccuracy in complex regions; (iii) Substantial variations in spatial consistency across different terrains, with LP showing the weakest consistency; (iv) CLC-HG's remarkable performanced in identifying diverse LC types, boasting 85% overall accuracy; (v) Notable progress in classification accuracy with CLC-HG, uncovering the nuanced influences of land category complexity on consistency and human interventions on accuracy. This study breaks new ground by integrating multidimensional data and methodologies, contributing valuable insights for classification enhancements and more adept land resource management. The pioneering CLC-HGproduct holds significant potential to reduce uncertainties in global environmental change studies, ecosystem evaluations, and hazard assessments, marking an important step forward in remote sensing applications.

How to cite: Chen, L.: Multisource fusion for high-accuracy land cover mapping: A 10m resolution strategy in China's hill and gully regions , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9379, https://doi.org/10.5194/egusphere-egu24-9379, 2024.

African tropical ecosystems possess great potential for nature-based solutions in mitigating fossil fuel emissions through absorbing and storing carbon in soil and vegetation. However, past studies mostly focused on pan-continental carbon balance quantification, often ignoring regional differences. Remarkably, few science-informed attempts have been made to refine carbon flux estimates at the national level within African rainforest countries. Yet, such refined estimates are essential to improve the quantification of Nationally Determined Contributions for the United Nations Framework Convention on Climate Change.

In this contribution, we present preliminary results on quantifying national carbon budgets for African rainforest countries by disentangling three major carbon fluxes for the period 2001-2015: (1) net carbon uptake in tropical savannas, woodlands, and forests, (2) carbon losses from land-use change, and (3) fossil fuel emissions. Carbon fluxes in intact forests are quantified using ground-based data¹, while the carbon uptake by intact savannas and woodlands is based on Net Primary Productivity assessments estimated from remote sensing products^2,3. Furthermore, carbon emissions from land-use change are estimated by analyzing various satellite images and related products providing data on land-use change^4–6, soil and tree carbon stocks^7–12, fire emissions^3,13,14, and carbon recovery in regrowing forests^15–18 in tropical Africa. Country-level fossil fuel emissions are taken from the Global Carbon Project database¹⁹ to complete the national carbon balances.

We reveal that most Central and East African rainforest countries acted as net carbon sinks between 2001 and 2015, while West African rainforest countries exhibited minimal net carbon loss. Overall, tropical ecosystems have played an important role in mitigating carbon emissions due to land-use change and fossil fuels in African rainforest countries, particularly in Congo Basin countries. Our insights into nation-level carbon fluxes will be crucial for informing African rainforest countries, guiding climate policies to stay on track to keep global warming well below 2°C.

References:

1. Hubau, W. et al. Nature 579, 80–87 (2020).
2. Running, S.W. et al. BioScience 54, 547-560 (2004).
3. Randerson, J.T. et al. (2018).
4. Hansen, M.C. et al. Science (1979) 342, 846–850 (2013).
5. Vancutsem, C. et al. Sci Adv 7, eabe1603 (2021).
6. Curtis, P.G. et al. Science (1979) 361, 1108–1111 (2018).
7. Simard, M. et al. Nat Geosci 12, 40–45 (2019).
8. Avitabile, V. et al. Glob Chang Biol 22, 1406–1420 (2016).
9. Zarin, D.J. et al. Glob Chang Biol 22, 1336–1347 (2016).
10. Saatchi, S.S. et al. Proc Natl Acad Sci USA 108, 9899–9904 (2011).
11. Baccini, A. et al. Nat Clim Chang 2, 182–185 (2012).
12. Poggio, L. et al. SOIL 7, 217–240 (2021).
13. Van Wees, D. et al. Geosci Model Dev 15, 8411–8437 (2022).
14. Di Giuseppe, F. et al. Atmos Chem Phys 18, 5359–5370 (2018).
15. Heinrich, V.H.A. et al. Nature 615, 436–442 (2023).
16. Deklerck, V. et al. Biol Conserv 233, 118–130 (2019).
17. Cook-Patton, S.C. et al. Nature 585, 545–550 (2020).
18. IPCC. 6 (2006).
19. Friedlingstein, P. et al. 14, 4811–4900 (2022).

How to cite: Verbiest, W. W., Ewango, C. E., Makana, J.-R., Lewis, S., Bauters, M., Bastin, J.-F., Fayolle, A., Gorel, A.-P., and Hubau, W.: Disentangling national carbon fluxes of African rainforest countries., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9583, https://doi.org/10.5194/egusphere-egu24-9583, 2024.

In recent years, there has been an increased interest in technologies such as Vortex-induced vibration energy harvesters (VIV-EH) concerning the potential to harvest and utilise the energy potential in oceans, rivers, channels and water pipelines. VIV-EH could be an ideal solution for energy generation through harvesting the kinetic energy from flow-induced vibration in open water systems such as rivers, lakes and lagoons, as well as closed water systems like water pipe systems in water and energy infrastructure. The energy generated could enable a self-powered sensor monitoring system and, therefore, replace the need for batteries or diesel generators to power the monitoring system, enhancing the water system's reliability. One of the applications explored for deploying VIV-EHs is installing into existing water pipelines to harness the flow vibration for energy generation. Assessing the feasibility of new energy technology such as VIV-EH is crucial to successfully implementing any technology into the pre-existing system. To fully determine feasibility requires information and inputs attained from assessing multiple cross-dimensional factors, which can provide information on the positive and negative economic, environmental and societal impacts and technological barriers or opportunities related to implementing this technology to any existing system infrastructure. To address this, an assessment framework is being developed, incorporating data and calculations from Life Cycle Assessment for calculating environmental impacts, MatLab for calculating the VIV-EHs key characteristics, and stakeholder engagement for assessing the selection of crucial evaluation metrics. The assessment tool will allow the user to carry out a multi-dimensional (Socio-Economic, Technical, Environmental) or single-dimension feasibility assessment concerning the integration of VIV-EHs into existing water infrastructure using a web-based tool. The application of the assessment framework provides critical informations such as VIV-EH's energy generation potential and role in the energy transition towards a cleaner and green energy system, which are relevant to designing a technology implementation strategy. The framework is applied, tested and used to evaluate the potential of VIV-EHs in various case studies: i) a geothermal district heating network in Reykjavik, Iceland; ii) a drinking water supply system in Ferlach, Austria, and iii) the MOSE flood protection in the Lagoon of Venice, Italy. Preliminary results suggest that the VIV-EH can reach capacities to supply sufficient energy – measured in watts – to power sensors for monitoring, maintenance and operation of water infrastructure. This continuous supply for monitoring networks can increase the resilience of water infrastructure and improve water resource utilisation, which is becoming more critical during climate change. The findings will be used to develop the assessment tool further and provide information that can help build a strategy for deploying VIV-EHs into water and energy infrastructure across Europe. The framework is tested on representative case studies across Europe but can potentially be applied in any energy system worldwide.

How to cite: Guðlaugsson, B., Secnik, M., Stepanovic, I., Bronkema, B., Hocevar, M., and Finger, D.: Multi-Dimensional Feasibility Assessment of the Deployment of Vortex-induced vibration Energy Harvester to utilize hidden hydro potential in European water and energy infrastructure, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10664, https://doi.org/10.5194/egusphere-egu24-10664, 2024.

The transition away from fossil fuels involves management challenges since the socioeconomic prosperity of the affected areas should be assured. This study assesses the mechanisms, and the future planning of two European regions - Rhenish in Germany, and Western Macedonia in Greece – currently under decarbonization. The assessment is grounded in the application of the five EU - recommended tools, i.e., the governance tools, the sustainable employment and welfare support toolkit, the environmental rehabilitation and repurposing toolkit, the financial toolkit and the technology options toolkit. Rhenish region is targeting for lignite phase-out by 2038 whilst Western Macedonia has set a target for the completion of the transition away from lignite by 2028. The analysis carried out here has shown that both regions have adopted comprehensive strategic plans, delineated transition roadmaps, and established economic models. In particular, both regions have similar governance structures in place and have adopted comparable action plans for sustainable employment and welfare support. However, Western Macedonia faces some implementation challenges and delays in the sector of Reclamation and repurposing efforts. The financial structure of both regions is similar, with the EU and the state being the primary funding sources. Both regions are primarily considering technology options that prioritize the repurposing of power plants, the reduction of carbon emissions in energy-intensive industries, the utilization of hydrogen technologies, and non-electric carbon applications. The findings of this work will contribute to the development of viable strategies for coal transition in diverse national contexts. By thoroughly evaluating the experiences of these locations, this work aims to inform policymakers and stakeholders about effective approaches to navigate the challenges associated with decarbonization while ensuring sustained prosperity in affected areas.

How to cite: Tagaris, E., Tranoulidis, A., Sotiropoulou, R.-E. P., and Bithas, K.: Transition towards low-carbon emissions: A Comparative Analysis between Western Macedonia (Greece) and Rhenish (Germany), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11334, https://doi.org/10.5194/egusphere-egu24-11334, 2024.

Abstract

Energy storage systems (ESS) are required to overcome the challenges of large-scale integration of variable renewable energy. Specifically, offshore ESS can increase the utilisation of offshore transmission cables and reduce stress on the grid. Marine pumped hydro storage (PHS) is a promising technology in this domain [1]. This study focuses on the role of a subsea PHS system in offshore wind farms, taking the Dutch North Sea as a case study. This novel technology stores electricity on the seabed by pumping water to a reservoir subject to the hydrostatic pressure of the overlying seawater, and releases it by letting the water flow back through a set of turbines to a second reservoir at atmospheric pressure, thus utilising the change in potential energy associated with pressure difference.

Anthropogenic activities increasingly deploy marine environments as sites of operation. Besides traditional uses like fisheries, navigation, defence and
mining, the climate and biodiversity crises respectively call for the uptake of offshore renewable energy systems and biodiversity-enhancing structures such as artificial reefs. These activities affect the marine host ecosystems, though impacts can be both beneficial (providing artificial habitats) and detrimental (disturbing species) [2].

The European Topic Centre on Inland, Coastal and Marine waters highlights the importance of marine spatial planning and environmental impact assessment (EIA) methods in elucidating conflicts of interest between the development of offshore renewable energy and protection of the marine environment [3]. Though the environmental impacts of offshore renewable energy projects such as wind and even wave farms have been investigated and are safeguarded by EIA legislation, only few studies can be found on offshore energy storage. Research on offshore ESS mainly focuses on either the (life-cycle) environmental impacts of a technology, or on the technical and/or economic performance in terms of efficiency, feasibility or costs and benefits. The combination is lacking for specific technologies and areas, such as subsea PHS. Therefore, this study integrates a techno-economic modelling approach with EIA methodology with the objective of obtaining the techno-environmental potential of subsea PHS as a novel offshore energy storage system.

First, a literature review is conducted to compose a framework for the assessment of biological, chemical and physical impacts of offshore energy storage systems, consisting of a list of impact indicators and, if available, threshold values. Second, the framework is applied to a case study of subsea PHS in the Dutch North Sea. The technical potential, i.e., the optimal installed capacity from a technical point of view, is determined by modelling the Dutch planned offshore wind farms until 2030, allowing for installation of the storage technology to minimise curtailment of wind energy in the system. The model is formulated as a mixed-integer linear program. Third, the impact indicators are investigated for the resulting technology size and, taking threshold values into account, the environmental potential is determined. Last, trade-offs between technical performance and ecological effects are identified and discussed.

References

[1] Wang et al. A review of marine renewable energy storage. International Journal of Energy Research, 2019.
[2] Taormina et al. A review of methods and indicators used to evaluate the ecological modifications generated by artificial structures on marine ecosystems. Journal of Environmental Management, 2022.
[3] Galparsoro et al. Mapping potential environmental impacts of offshore renewable energy. European Topic Centre on Inland, Coastal and Marine waters, 2022.

How to cite: Ossentjuk, I., Wiegner, J., Nienhuis, R., Griffioen, J., Vakis, A., and Gazzani, M.: The techno-environmental potential of offshore pumped hydro storage: A case study of the Dutch North Sea, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12276, https://doi.org/10.5194/egusphere-egu24-12276, 2024.

Soil organic carbon dynamics are strongly influenced by soil and climate conditions, as well as management practices including grazing and cropping. Over the past two decades, biogeochemical models have been widely used for analysing the effect of different environmental and management variables on soil carbon, including potential change under hypothetical future climate and management scenarios. The DayCent model, which is a daily implementation of the Century model, considers the impacts of soil texture, climate, historical vegetation cover, and land management practices, including crop type, fertilizer additions, and cultivation events on soil carbon dynamics.

In this study, we calibrate the DayCent model for two long-term (38-year) native pasture exclosures at one location in south-eastern Queensland. These sites have had similar management, being ungrazed and burnt or mown at the beginning of each pasture growing season but differ with respect to soil type (texture and depth) and species composition. One site is dominated by kangaroo grass (Themeda triandra), which represents the species composition prior to the introduction of tree clearing and grazing by cattle in the late 1800s. The other site is dominated by black spear grass (Heteropogon contortus) which has become the dominant species in the region since that time. To reflect the long-term species composition changes in the region, kangaroo grass crop parameters were used to run the model to equilibrium from year 1 AD to the year 1900 for both sites, and spear grass parameters were introduced in 1901 for the spear grass site.

The model calibration concentrated on the key ‘crop’ parameters governing potential production, root to shoot ratio, and plant carbon to nitrogen ratio. The calibrated DayCent model accounted for only 21 percent of the observed year-to-year variability in end-of-season above-ground biomass at the kangaroo grass site and 58%  at the spear grass site. The observed biomass production for the two sites was most strongly correlated with simulated evapotranspiration during the growing season (R² = 0.43 and 0.58 for kangaroo grass and spear grass respectively) and we found a strong correlation between simulated and observed soil water content to a depth of 50 cm at both sites (R² = 0.64 and 0.6 for kangaroo grass and speargrass respectively).

Whilst year-to-year variability was not well simulated, the long-term average production of each site is the main driver of soil carbon. For both sites, the model overestimated the average observed above-ground biomass at the end of the growing season by approximately 15 percent. By this time of year, the plants have flowered and lost biomass through the detachment of seeds and seed heads as well as some dead leaves. The timing of this detachment process is difficult to simulate in DayCent and it is therefore likely that DayCent simulated the annual biomass production quite closely. It remains to validate the DayCent simulations against similar long-term production data at a further six long-term study sites at this location and to evaluate how well DayCent simulates observed soil carbon across soil types, both under grazed and ungrazed conditions.

How to cite: Mirsafi, Z., Day, K., Parton, W., Takeda, N., and Rowlings, D.: Calibration of the DayCent Model for Native Pastures in South-Eastern Queensland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13162, https://doi.org/10.5194/egusphere-egu24-13162, 2024.

Against the backdrop of the rapid global rise of solar photovoltaic (PV) energy, its supply chain from manufacturing to installation has gradually exhibited dynamic spatial evolution, yet the spatiotemporal distribution of greenhouse gas emissions and mitigation throughout the entire PV industry chain has not received sufficient attention. The pathways to enhance the net mitigation benefits of PV through international collaboration across the entire industrial chain remains in its initial stage. This presentation will outline the author's systematic accounting of global supply chain carbon emissions and mitigation, combining spatiotemporal dynamic lifecycle assessments and scenario analyses. The analysis explored the spatiotemporal evolution of net greenhouse gas mitigation from 2009 to 2060 within the global PV industry. The study reveals that optimized collaboration between manufacturing and installation globally could increase the net mitigation effects of the entire industrial chain by 97.5 Gt carbon dioxide equivalent, equivalent to 1.9 times the global GHG emissions in 2020. This finding provides theoretical and empirical support for enhancing international strategic cooperation to enhance global greenhouse gas mitigation.

How to cite: Chen, S. and Lu, X.:  Greenhouse gas emissions and mitigation in the global solar photovoltaic industry chain, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13733, https://doi.org/10.5194/egusphere-egu24-13733, 2024.

The rapid expansion of renewable energy and the imperative for carbon reduction have prompted significant coal phase-outs. Coal is the largest contributor to energy-related carbon emissions globally, accounting for over one-third of the total. Coal-fired electric generating units (EGUs) play a significant role in these emissions, with over 5,000 units in China contributing to around 15% of global carbon emissions. These units, relatively young with an average age of less than 15 years, are facing challenges such as the absence of power purchase agreements, the prospect of early retirement, amid renewable energy growth, and ongoing retrofits for energy efficiency and carbon reduction. The transition pathway of the coal-fired power sector is crucial for its evolution and the integration of renewable energy. Hence, a data-driven optimization prediction model is introduced in this study, aiming to delineate an optimal transition pathway for the coal-fired power sector under different scenarios, guiding its evolution towards a low-carbon energy system.

The model comprises two modules: the phase-out module and the retrofit optimization prediction module. A unified unit-level database, encompassing operational data from over 5000 coal-fired EGUs in China, as well as techno-economic information associated with 21 types of carbon reduction retrofits, serves as the foundation for the most cost-effective pathway towards a low-carbon transition in the power sector. The phase-out module predicts the phase-out and remaining capacities, including the potential portion replaced by renewable energy. The phase-out determination involves assessing the cost of replacing coal-fired power with renewable power generation, along with considerations of the economics and carbon emissions associated with units under normal operation before retirement. This laterally furnishes valuable information for comprehending the potential capacity for renewable generation, ensuring that the transition pathways in the coal-fired sector are realized in a manner that safeguards the stability and reliability of the future power system. The optimization prediction model employs machine learning algorithms consisting of the predictor and the optimizer. The predictor provides estimates for overall carbon reduction potential (CRP) for the coal-fired power sector, even for the power sector, as well as near-term levelized costs of carbon emissions reduction (LCOC) and electricity (LCOE), approached from the unit-level perspective. The optimizer identifies portfolios that maximize carbon emission potential while minimizing costs. This study ultimately provides a comprehensive analysis of the low-carbon transition pathway for the primary source of emissions in the energy sector, namely the coal-fired power sector, conducted from both techno-economic and environmental (specifically carbon reduction) standpoints, employing an optimization prediction model.

How to cite: Zhao, X., Zhang, L., Wang, X., Zhu, C., Wang, K., Ni, Y., Pan, J., Yang, L., Su, Y., and Zheng, C.: Optimal Transition Pathways Toward a Low-Carbon Energy System in China: a Data-Driven Optimization Prediction Model in Machine Learning., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13747, https://doi.org/10.5194/egusphere-egu24-13747, 2024.

In Taiwan's rural areas, significant changes are underway in the once-predominant focus on traditional agriculture. The current landscape in rural areas is characterized not only by the presence of numerous factories but also by the increasing solar panels, driven by the ongoing transition to renewable energy sources. Despite numerous studies confirming the correlation between land use and temperature in urban areas, limited thermal research has been conducted in rural regions. Additionally, rural residents, particularly the elderly, are more sensitive to temperature variations.

The purpose of this study is to investigate whether the construction of iron rooftop factories and rooftop solar panel structures in rural environments results in significant differences in surface temperature and surrounding land use, thereby revealing the thermal impacts of these structures.Three coastal towns in central Taiwan were selected as the primary study area due to their higher density of solar panels and similar agricultural characteristics. Landsat 8 surface temperature data were utilized, with buffer zones established at 30-meter intervals from sample boundaries to explore variations in surface temperature and land use characteristics.

The findings reveal that rooftop solar panels and iron factories are predominantly surrounded by arid fields. As the distance from rooftop solar panels increases, the surface temperature gradually decreases, returning to ambient levels. However, no discernible changes in surface temperature were observed around iron rooftop factories. This study not only sheds light on the thermal impacts of these structures in rural environments but also points out the importance of land use control on thermal environments.

How to cite: Lee, Y.-J., Chung, M.-K., and Tseng, W.-L.: Coexisting Agriculture, Industry, and Energy in Rural Areas： Comparative Surrounding Surface Temperatures between Rooftop Solar Panels and Iron Rooftop in the Yunlin, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13845, https://doi.org/10.5194/egusphere-egu24-13845, 2024.

The changes in Land Use and Land Cover (LULC) have multifaceted impacts on sustainable development. Among the main ecosystem services acting on the environment, the Carbon Storage and Sequestration consists of the process of removing carbon from the atmosphere and its subsequent incorporation or storage in the form of biomass. Therefore, its understanding and modeling allow the control and instrumentalization of the biological absorption of carbon by the soil and, consequently, the reduction of the amount of greenhouse gases (GHG) in the atmosphere. To unravel this intricate ecosystem service, this study employs the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) methodology, specifically the Carbon Storage and Sequestration (CSS) model, within the municipality of Itaperuna in the northwest of the state of Rio de Janeiro (RJ), Brazil. This model estimates the amount of carbon stored in an area, calculates the variations that have occurred, and predicts future storage in the same region. It does so by analyzing land use and land cover, estimating carbon sequestration alterations between different scenarios, and assessing their monetary worth. To undertake this analysis effectively, three key pieces of information are essential: delineation of two LULC scenarios (e.g., 2015 and 2020), carbon content across various LULC classes, and the Social Cost of Carbon (SCC), which evaluates potential socioeconomic repercussions due to climate change for each ton of carbon emitted. This investigation aims not only to comprehend the dynamics of land use and land cover alterations in a medium-sized city within this region but also to estimate changes in carbon stocks and sequestration resulting from LULC transformations. The study further intends to quantify the financial implications of these alterations through the application of SCC.

How to cite: Paz, I., Celebrini de Oliveira Campos, P., Barros Felix, N., and Soares Marques, M. E.: GIS Assessment of Carbon Storage and Sequestration Impact Caused by Urban Development in Itaperuna-RJ, Brazil, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13941, https://doi.org/10.5194/egusphere-egu24-13941, 2024.

The quantification of carbon sequestration in Urban Green Spaces (UGSs) is challenging due to their unique characteristics such as the fragmentation of green spaces, human-influenced species selection, and varying management practices. IPCC guidelines recommend calculating carbon sequestration in UGSs per individual tree or crown cover area. Although crown cover area-based estimation is commonly used in national greenhouse gas inventories, research on the growth rate based on crown cover area (CRW) and the effects of varying sampling methodologies is limited. This research aimed to calculate CRW [ton C (ha crown cover)^-1 yr^-1] in South Korea using two distinct sampling methods. Method_SS (M_SS; Systematic Sampling Method) divided urban areas into 500m x 500m grids and selected a 5% sample (1,603 grids) randomly. Within each grid, three sites were chosen and vegetation at three points was surveyed. For analysis, only points with trees excluding shrubs were included. Method_CS (M_CS; Categorized Sampling Method) divided UGSs into three categories: street trees, urban parks, and others. For each category, 48 sites with three plots each were selected. In the street trees category, a plot consisted of 20 trees, while in urban parks and others, a plot was defined as a 20 x 20 m area. At each plot, species, diameter at breast height (DBH), height, and crown width of all trees were measured. For the derivation of CRW, a total of 8,037 and 5,733 trees were used in M_SS and M_CS, respectively. CRW was calculated in four steps: 1) The carbon storage of individual trees (C_t1) was calculated using allometric equations and the carbon fraction. 2) The carbon storage from one year prior (C_t2) was estimated based on the annual DBH growth rate (cm yr^-1). 3) The annual carbon accumulation (kg C tree^-1 yr^-1) was calculated as the difference between C_t1 and C_t2. 4) CRW was calculated by dividing the total annual carbon accumulation by the total crown cover area of the surveyed trees. As a result, The study revealed a notable difference in CRW between M_SS and M_CS. M_SS reported CRW of 0.23 ton C ha^-1 yr^-1, while M_CS presented 0.30 ton C ha^-1 yr^-1. When categorized by land use, CRW was found to be highest in urban parks followed by others and street trees. In M_SS, the diverse sample locations resulted in a wider range of DBH values, including many large-sized trees (DBH ≥ 70 cm). The lower CRW estimates in M_SS were primarily due to the assumption that large-sized trees had zero annual carbon sequestration following the IPCC guidelines. This led to a higher inclusion of large-sized trees in M_SS, resulting in lower CRW values. Also, there were significant differences in species distribution, tree sizes (DBH), and CRW, depending on the sampling methodology. These variances are primarily due to the unique characteristics of UGSs. The study highlights the necessity for further research into more representative sampling methodologies for estimating carbon sequestration in UGSs.

How to cite: Lee, J., Jo, H., Kim, W., and Son, Y.: Annual Carbon Sequestration Per Crown Cover Area of Urban Green Spaces in  South Korea: Comparative Analysis Using Different Sampling Methodologies, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14214, https://doi.org/10.5194/egusphere-egu24-14214, 2024.

The reduction of carbon dioxide levels in the atmosphere is one of the most pressing issues in the context of global warming. Forest ecosystems play a crucial role in carbon cycling due to their ability to store significant amounts of carbon in plant biomass, deadwood and soil. Research on deadwood has usually focused on the analysis of the current state without considering the history of forest stands. However, a recent trend in many European countries is to increase the area and number of protected areas, often encompassing previously managed forests. Such changes in forest management affect the abundance and character of deadwood, and thus and need to be considered in the analysis of its carbon storage capacity.

The forests of Wielkopolski National Park in Poland are an excellent subject for such research. Until the end of the 18th century, they were owned by various landowners, leading to a highly diversified forest management driven by immediate needs of owners. In 1931, the first reserve, where logging was discontinued, was established. The current strict protection areas were mostly designated in 1957 when the park was legally established. Currently, strict protection mainly applies to habitats of oak-hornbeam forests Galio sylvatici-Carpinetum betuli, with other communities represented to a lesser extent.

The assessment of deadwood carbon stock (DWCstock) was performed using the data from the field survey conducted between 2017 and 2018. Deadwood was inventoried at 98 circular plots (0.04 ha) located inside 12 strictly protected areas. We distinguished five deadwood categories: standing snags, logs, stumps, branches, and twigs, and 5 decay classes. All dead trees and their parts with a minimum top diameter of 3 cm were measured. The small diameter threshold was selected due to the abundant presence of shrubs that ocurrred during the 'renaturalization' of forest ecosystems. From the measured dimensions we derived DWCstock using species- and decay-specific volume equations, wood density and carbon fraction values. The data were stored in a relational database and further processed and statistically analysed in the R environment. 

The analysis showed a high variability of DWCstock between plots (from 0.19 to 92.43tC/ha, mean 15.03tC/ha). Almost 50% of the total DWCstock was assigned the third decay stage, while 10 and 5% of DWCstock occurred in the first and last decay stage, respectively. This indicates a substantial accumulation of the deadwood after the abandonement of forest management. In 60% of cases, the dominant species of deadwood did not coincide with the dominant species of the currently living trees suggesting the changes in species composition of forest ecosystems over time. The results show deadwood can be considered as a long-term memory of forest dynamics. The work highlights the need to use multiple data sources for a better understanding of ecosystem development.

How to cite: Merganicova, K., Nowinska, R., Merganic, J., and Kaczmarek, L.: Impact of recent forest protection on deadwood carbon stocks, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18737, https://doi.org/10.5194/egusphere-egu24-18737, 2024.

China and India, two of the world's leading carbon emitters, have pledged to achieve carbon neutrality by mid-century in alignment with the Paris Agreement. Central to this ambition is the electrification of their economies, and both nations have made significant strides in recent years. Yet, a thorough cost-benefit analysis of their energy transition progress and future energy transition pathways remains lacking. Here we adopt nine comprehensive models to assess the region-specific co-benefits related to carbon emission, air pollution, health and employment of energy transition in the power sector in China and India from 2015-2020 and further explore their most cost-effective pathways towards 1.5°C and 2°C scenarios in 2030-2050. We find that although the emissions contributed by the power sector in China and India from 2015 to 2020 resulted in more than 10,000 PM_2.5 attributable deaths in 2020, the economic benefit of job creation of new installation of renewable power in 2020 was 68 (95% CI: 56-93) times and 6 (95% CI: 5-7) times than the monetary of health loss. Under the SSP1_RCP2.6 scenario, it will ultimately achieve the largest benefit (monetary health co-benefits) to cost (carbon mitigation cost) ratio for both countries in 2050, and India (14.6 (95% CI: 12.7-16.1) will obtain a larger ratio than that of China (4.1 (95% CI: 3.3-4.7)). We recommend both nations deepen their commitment to power sector transition, prioritizing low-carbon fuels and expanding education and skill training to support the emerging new energy economy.

How to cite: Lu, C.: Co-benefits and cost-benefit analysis of energy transition in the power sector in China and India, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20459, https://doi.org/10.5194/egusphere-egu24-20459, 2024.

Urbanization has led to significant shifts in both natural resource utilization and human activities. The equilibrium between energy and other resources has been disrupted by the concentration of urban populations and the environmental repercussions of economic growth. This issue is of paramount importance on both global and regional scales. Among the various facets of urban life, the transportation sector, an indispensable urban function, is predominantly associated with issues such as pollution, traffic congestion, and inadequate public transportation systems.
This research presents a framework for achieving sustainable development objectives in urban transportation by phasing out diesel-powered vehicles in favor of electric ones. The implementation of electric vehicle policies holds the potential to mitigate urban air pollution. Nonetheless, if the government fails to consider the interplay between various policies during the evaluation process, unintended environmental consequences may emerge.

For instance, while electric vehicles that supplant traditional gasoline and diesel counterparts do not emit pollutants during their operation, they may shift the burden to power plants, necessitating a more diverse range of resources. As such, a comprehensive assessment of the overall environmental impact becomes imperative.

Hence, in this study, we initially focus on motorcycle batteries as a case in point. We employ methodologies such as material flow analysis, life cycle assessment, and real-world factory inventory to examine the resource consumption across various stages of battery production. Subsequently, we gauge the implications using distinct sustainability and environmental management criteria pertinent to diverse urban settings and resource management strategies. The resulting data is then amalgamated into a comprehensive environmental assessment.

In addition, we account for variations in battery reuse rates, such as repurposing them as energy storage units. Ultimately, these scenarios are scrutinized to gain insight into the divergent environmental repercussions associated with different reuse approaches

How to cite: Wang, Y.-S. and Kuo, N.: Life cycle Assessment of different waste electric vehicle battery reuse strategy – a case study in Taipei , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20500, https://doi.org/10.5194/egusphere-egu24-20500, 2024.

In recent years, landscapes in many countries have been transformed by efforts to fight global warming, specifically the shift towards renewable energies. Photovoltaics is one of the key technologies for reducing greenhouse gas emissions and achieving climate neutrality for Europe by 2050, which has led to the promotion of solar parks. Due to the ambitious goals for the expansion of photovoltaics, a multiple of the area used so far will be built on with solar parks. These parks are often built on arable land, can span up to several hundred hectares, and grassland vegetation is usually created between and under the panels. In most cases, this is done by spontaneous revegetation or by seeding species-poor mixtures dominated by grasses.

In a case study of 12 spontaneously planted solar parks in a structurally poor agricultural landscape in central Germany, we found an average of 90 vascular plant species. However, the number of target grassland species is only one third and the majority are ruderal species. A comparison of the three zones showed that there were the same number of target grassland species in the area between the panels and without panels, but significantly fewer under the panels. Surprisingly, the coverage of target grassland species was highest between the panels.

Establishing grasslands using highly divers native seed mixtures can significantly enhance target species richness. This finding has already been well documented by grassland restoration research. However, it has not yet been proven for solar parks with their special characteristics, such as small-scale modified site conditions. In two solar parks on ex-arable land, we seeded a site adapted seed mixture with high percentage of forb seeds (39 species, including 3 grasses). In the first year after sowing, the establishment success of the sown species in the areas between the PV panels were recorded. The establishment rate was 25-30 % in the unshaded sections, increased significantly in the partially shaded sections and fell sharply with increasing shade. The low establishment rate is probably related to the significantly below-average rainfall in 2021, while the partially shaded sections provided better establishment conditions due to higher soil moisture. Heavy shading hindered the establishment of light-demanding grassland species. An increasing establishment rate is expected in the further vegetation development and must continue to be monitored.

How to cite: Dullau, S., Meyer, M. H., Scholz, P., and Tischew, S.: Grassland establishment in solar parks on former arable land - spontaneous succession and first findings of a highly divers seed-based approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20934, https://doi.org/10.5194/egusphere-egu24-20934, 2024.

Litter stores around 5% of total carbon (C) stocks in the World's forests (Pan et al. 2011) and is one of five forest ecosystem C pools in national greenhouse gas (GHG) inventory reports, for which reporting is mandatory. Litter is known for its high spatial heterogeneity at different scales. Litter mass, and therefore its C stock, varies with respect to climate region, forest type, and various site and stand characteristics. Litter in the context of GHG reporting in Croatia corresponds to the forest floor (undecomposed leaf organic layer – OL, and fragmented and humified organic layer – OFH), while emissions and removals from the Forest land category, which includes the Litter pool, are stratified into Broadleaves and Conifers. Although a relatively small country in Europe, the biogeographical diversity of Croatia is high, which leads to the question if the existing stratification for the litter should be refined. We tested the hypothesis that litter C stocks within specific tree species groups (Broadleaves and Conifers) differ between biogeographical regions (BGR).

From available national data sources, we compiled a database on litter, soil and forest stand variables at 276 plots distributed across three BGRs in Croatia: Alpine, Continental and Mediterranean. Litter data includes height, dry mass, C stock and C/N. Soil data includes soil organic C (top 30 cm), soil texture and bulk density. Stand variables include main tree species, stand basal area and tree density. Additionally, the database includes information on mean annual temperature (MAT), mean annual precipitation (MAP) and elevation at the plot level. Data were analysed at different scales regarding three BGR and two tree species groups (Broadleaves and Conifers).

Litter C stocks showed high variability (CV>30%) at the regional scale, with the Mediterranean BGR having the highest variability (CV of 43%). When looking at the specific tree species group, coniferous forests in Mediterranean BGR have the highest averaged litter C stocks (8.13 tC ha^-1), while the broadleaf forests in Continental BGR have the lowest averaged litter C stocks (4.37 tC ha^-1). Litter C stocks significantly differ between Alpine and Mediterranean BGR in coniferous forests, while in broadleaf forests significant difference in litter C stocks was observed between Alpine and Continental BGR. Our results indicate that the stratification of the Litter with respect to BGRs may improve the accuracy of the national carbon inventory.

How to cite: Bitunjac, D., Ostrogović Sever, M. Z., Bakšić, D., Anić, M., and Marjanović, H.: Variability of litter carbon stocks in Croatia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21320, https://doi.org/10.5194/egusphere-egu24-21320, 2024.

Soil organic carbon (SOC) is a key property of soil quality in arable soils and can play a central role in the voluntary carbon credit market by improving soil health, future food security and mitigating against climate change. The adoption of regenerative agricultural practices are considered one solution to achieve increases in SOC sequestration rates. However, the spatiotemporal dynamics of SOC mean the changes in SOC attributed to management practices are often difficult to detect across different spatial scales and over short temporal periods. Thus, rapid, cost-effective methods for quantifying carbon are sought by key stakeholders in both academia and industry for accurate accounting of SOC stocks. A field trial experiment was conducted in 2023 on five arable fields in Denmark to compare SOC stocks measured between: (i) the conventional sampling method and (ii) a portable, handheld visible near infrared (NIR) spectrometer. The conventional sampling method used a hydraulic corer to extract soil in each field (n=9) split into three depth increments (0-15, 15-30 and 30-60 cm). The samples were analysed for %SOC by the dumas dry combustion method whilst bulk density was measured volumetrically from the intact core upon extraction. For the spectroscopy method, soil was first extracted using a handheld auger (0-30 cm) which was subsequently homogenised and soil properties (%SOC, %Clay content and bulk density) were measured in situ by the scanner. The SOC concentration of these in situ soil samples were also measured by dry combustion analysis. We found differences in cumulative SOC stocks between the conventional and NIR methods attributed to variation in how SOC concentration was measured (directly vs. dry combustion) and less so to variation in bulk density. Clay contents were also similar between the conventional sampled soils and NIR soils, whilst the SOC concentrations measured by dry combustion were similar for both conventional and NIR soils. Overall, the results highlight that portable vis-NIR spectroscopy could be a scalable solution for monitoring SOC stocks in arable soils.

How to cite: O'Neill, M., Alves, M., Manderson, A., Macdonald, R., and Georgiadis, P.: Intercomparison of soil organic carbon stocks measured from conventional and in situ sampling techniques at different spatial scales, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21950, https://doi.org/10.5194/egusphere-egu24-21950, 2024.

The transition towards a decarbonized electricity system, based on renewable energies, is urgently needed to achieve the so-called carbon neutrality and help mitigating climate change, among other reasons. At the same time, there is a need for electricity production from renewable energies to be stable in time, or to follow the demand, without substantial fluctuations. The open-access step-wise model called CLIMAX exploits the fact that wind and solar photovoltaic (PV) power present a certain degree of spatio-temporal complementarity in order to reduce the volatility of their combined production at its minimum. In a previous study, CLIMAX was used to identify optimum deployments of PV and wind power facilities across five European domains (Jerez et al., 2023). Here, using these optimum capacity density scenarios, the installed capacity per European country for the period 2012-2020 as reported in IRENA (2020), and ERA5 reanalysis data for the same period, are used to compute capacity factors, and the wind-plus-solar electricity production is estimated and compared to that from a BASE scenario with a homogeneous spatial distribution of installations. Results show that the optimization of the spatial distribution of the wind-plus-solar installed capacities does not only enhance the stability of the energy production in time, but also in terms of mean values (i.e. efficiency). More precisely, an average improvement in the energy production of +47.5 TW·h per year, integrated over Europe, is obtained as compared to BASE. Consequently, pollutant emissions from thermal power plants could have been reduced if electricity would have been produced from these renewable sources. In this work, this reduction is estimated and, in a last step, the potential reduction of human deaths related to air pollution is also evaluated. Results encourage further efforts towards a low-carbon energy future.

REFERENCES:

Jerez, S., Barriopedro, D., García-López, A., Lorente-Plazas, R., Somoza, A. M., Turco, M., et al. (2023). An action-oriented approach to make the most of the wind and solar power complementarity. Earth's Future, 11, e2022EF003332. https://doi.org/10.1029/2022EF003332.

IRENA. (2020). Renewable capacity statistics 2020. International Renewable Energy Agency (IRENA).

How to cite: Gallardo, V., Jiménez-Guerrero, P., and Jerez, S.: Optimized renewable energy production for a low-carbon future to mitigate climate change and associated health impacts, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22105, https://doi.org/10.5194/egusphere-egu24-22105, 2024.

Worldwide changes in the land use and climate are the main drivers that have triggered a decline in both biological and cultural diversities, and the degradation of ecosystems. In countries like Brazil, deforestation is the main source of greenhouse gas emissions, and it is increased, in some cases, by the degradation. As response to those challenges, degraded areas have emerged as a promising option for cultivating biomass to produce biorenewables, aligning with the concept of a 'green transition'. Brazil stands out as a viable region for new cropland requirement to address the global demand for biorenewables production. Nevertheless, despite the large areas of degraded pastureland in Brazil, identifying those for growing the crops avoiding worsening the principal causes of biodiversity loss is an issue to be addressed. We evaluated the ecological feasibility of degraded pasturelands as potential areas for biomass production. We selected four exclusion criteria based on the Brazilian legal framework and the conventions and agreements to which the country is a signatory. In 2021, Brazil had 98.1 Mha of degraded pasturelands with the largest portion (63.9 Mha) experiencing a moderate level of degradation, mostly in Amazon biome (22.3 Mha). In addition, Brazilian legislation for biofuels production (Renovabio) predicts the exclusion of Amazon and Pantanal (a Brazilian wetland) biomes as eligible areas. Those biomes were the first exclusion criteria, remaining 65.1 Mha after its exclusion. In terms of protected areas, another adopted criterion, the land of traditional populations evaluated contains fewer degraded areas (0.3 Mha), when compared to the other Brazilian conservation categories (1.2 Mha). In the excluded degraded pasturelands (55.8 Mha, in total), the restoration of native vegetation should be prioritized to enhance biodiversity loss and the mitigation of climate change. Restoration efforts may vary by region, but agroforestry systems using native species of the biome could be a positive alternative. In addition to prioritizing the recovery of habitat and biodiversity loss, this approach has the potential to decrease local social vulnerabilities and to promote sustainable biorenewables production. By prioritizing the conservation of biological diversity, Brazil still has 42.3 Mha available for biorenewables, which corresponds to almost the total area currently under soybean cultivation in the country. The greater availability of degraded pastureland areas is within the Brazilian savanna. In addition to be a biodiversity hotspot, the Brazilian savanna is also central to water supply, contributing to important river basins in the country. Future work should consider other criteria such as water scarcity and climate vulnerability since it is necessary to evaluate the whole biorenewables’ value chains to assure sustainability.

How to cite: Padgurschi, M., de Souza Henzler, D., Palma Petrielli, G., and A. D. Hernandes, T.: Degraded pasturelands for sustainable biorenewables production: an ecological approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22175, https://doi.org/10.5194/egusphere-egu24-22175, 2024.

This contribution presents one of the research directions of the project WATERISKULT (https://wateriskult.geoscienze.unipd.it), involving the decay of underwater archaeological sites, in particular of submerged structures and artifacts made of stone. The pilot sites of this project are located in the western, central, and eastern Mediterranean Sea, and include the Roman complex of Baia in Italy, the Hellenistic harbor of Amathus in Cyprus, and the Roman port structures of Anse des Laurons in France. Diving and sampling campaigns were organized therein in the first half of 2023, and were followed by laboratory analyses that explored the state of conservation of different archaeological stone materials (limestones, marbles, tuffs, sandstones, etc.). Microscopic techniques were applied for investigating the stone composition, biofouling, and chemical alteration, observing the surface and stratigraphic features of the sampled materials. Moreover, 3D morphometric techniques allowed for the quantification of the physical damage of the archaeological surfaces. The analytical results were combined with site-specific topographic information collected during the dives and environmental data provided by seawater monitoring agencies. In that way, the interaction between ancient materials and the underwater environment was explored, discussing the relationship between deterioration and a range of different stone and seawater properties.

How to cite: Germinario, L., Moro, I., Crocetta, F., Tomasin, P., Moschin, E., Cibecchini, F., Demesticha, S., Gallocchio, E., Gatt, J., and Mazzoli, C.: Stone decay in the underwater environment: examples from Mediterranean archaeological sites, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1188, https://doi.org/10.5194/egusphere-egu24-1188, 2024.

Carrara marble is widely used, in buildings and sculptures, in ancient and recent works. Yet, it can develop deteriorations over time, such as bowing, cracks, expansion, reduction of mechanical strength, when it is exposed to environmental conditions. Previous studies have shown that these deteriorations can result from exposure to temperature variations, and that they can be enhanced by additional humidity variations. However, the mechanisms at stake at the microstructure level are still not well-understood.

This work is therefore focused on the understanding of the degradation mechanisms induced on marble by temperature and humidity fluctuations. Laboratory experiments are carried out on Carrara marble samples first heated at different temperatures and then undergoing thermal, hygric, and thermo-hygric cycles. The temperature investigated during cycling belongs to the mild temperature range (40 – 105 °C) in order to simulate outdoor exposure conditions.

The mechanical state of Carrara marble samples is non-destructively monitored during the cycles with Nonlinear Resonant Ultrasound Spectroscopy (NRUS), through the evolution of resonant frequency and of nonclassical nonlinearity. The first parameter is related to sample stiffness, and the latter is highly sensitive to any change occurring at the microstructure level (micro cracks, friction, capillary effects, etc.). Additionally, microstructural characterization (mercury intrusion porosimetry, optical microscope and SEM observations) is made on marble samples to link the evolution of the NRUS parameters to the changes occurring in marble microstructure.

The impact of heating on marble is first studied for temperatures between 40 and 250 °C, and the progressive granular decohesion of the material is monitored with NRUS. Marble state is also characterized during adsorption-desorption cycles, which shows that relative humidity fluctuations alone do not induce permanent damage. Finally, the influence of thermal cycling at mild temperatures and the impact of combined temperature and relative humidity cycling are studied with NRUS.

How to cite: Chavazas, M.-L., Bromblet, P., Berthonneau, J., and Payan, C.: Thermo-hygric weathering of Carrara Gioia marble monitored with Nonlinear Resonant Ultrasound Spectroscopy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1312, https://doi.org/10.5194/egusphere-egu24-1312, 2024.

The integrated use of non-destructive geomatic and geophysical techniques such as close-range digital photogrammetry, laser scanner techniques, thermography, sonic and ultrasonic methods, resistivity, etc... for the diagnostics of the stone building materials of architectural structures has become increasingly dependent on the integration of different disciplines of applied research. As is well known many historic monuments are characterized by severe damage due to temporal degradation, problems caused by differential settlements of the foundations and various types of natural hazards. Therefore it is of great interest to test and develop effective, integrated non invasive procedures to detect the conservation state of the building materials of historic structures, and identify and prevent their potential vulnerability in order to preserve their intrinsic characteristics for a long time.

For extensive applications, as well as for investigations on monuments or large architectural elements, scanning and digital high resolution images are particularly useful, thanks to their limited cost, high production and relatively simple reproducibility of the tests. These techniques give useful information on the shallow conditions of the investigated materials. Geophysical techniques such as the ultrasonic and resistivity methods are non-invasive and are considered the most appropriate to evaluate the internal structure and assess the quality of the stone materials of the architectural heritage.

This paper presents an integrated approach that combines advanced geomatic survey procedures, such as close-range photogrammetry (CRP) based on high resolution images and Terrestrial Laser Scanner (TLS) techniques with a few geophysical techniques such as the ultrasonic and resistivity ones in order to test the effectiveness of the integrated approach in providing an effective diagnosis of stone building materials in the Basilica di San Saturnino (Cagliari – Italy). This Basilica is the oldest monument of the town of Cagliari (Italy) and represents an interesting synthesis of different construction techniques with heterogeneous stone materials of different origins. CRP and TLS were applied to the investigated elements with the aim of obtaining a natural colour texturized 2D-3D model with a calibrated scale and coordinates. The geometrical anomaly and reflectivity maps derived from the data of the CRP-TLS survey show the presence of some anomalies worthy of attention, but they were referred to the shallow materials. A further investigation on site using the ultrasonic pulse velocity (UPV) and electrical resistivity techniques were performed to investigate the materials in depth. The results of the CRP and TLS techniques allowed the best design of the ultrasonic and electrical techniques and also proved to be useful in the data interpretation phase.

Acknowledgements: The authors would like to thank the Ministero della Cultura - DIREZIONE GENERALE MUSEI - DIREZIONE REGIONALE MUSEI SARDEGNA (ITALY) for their kind permission to work on the San Saturnino Basilica.

How to cite: Casula, G., Fais, S., Cuccuru, F., Bianchi, M. G., Ligas, P., and Cannas, L.: A multidisciplinary approach for the diagnostics of the stone building materials of architectural structures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2818, https://doi.org/10.5194/egusphere-egu24-2818, 2024.

Interaction between the historical built environment and environmental pollution can result in the accumulation of weathering crust on building material surfaces. A subgroup of weathering crusts are black crusts, which consist of gypsum layers formed by sulfation on calcium-rich substrates. These crusts occur more often and are more pronounced in polluted environments such as urban settings. As a result, they can incorporate particulate matter, polyaromatic hydrocarbons, and heavy metals. Black crusts can act as non-selective passive samplers, accumulating distinct layers of air contaminants depending on historical pollution levels.
Existing studies provide only coarse-resolution reconstruction of pollution, differentiating solely between inner and outer crust layers. Just a few explore the correlation between different periods of exposure to pollution and the variation of the composition of these crusts. This study focuses on the stratigraphic analysis of black crusts to assess their potential as a reliable geochemical archive for the reconstruction of past anthropogenic pollution within urban settings.
Following technological developments in transportation and combustion, the composition of pollutants in the atmosphere has evolved over the centuries, likely reflected within weathering crusts where pollutants accumulate. For the identification of past air pollution signatures, lead can serve as a useful tracer due to its isotopes, their presence is the result of different historical pollution sources. Variations in the ratios of lead isotopes provide a means to attribute and differentiate among these pollution sources. For lead isotope analysis, high-resolution laser ablation mass spectrometry will be used to distinguish between 206Pb, 207Pb, and 208Pb.
This study deepens the understanding of localized pollution levels in urban settings, allowing the implementation of conservation interventions including cleaning and consolidation, strategies to mitigate the impact on human health, local ecosystems, and biodiversity, and to support urban planning.

How to cite: Deboli, S., Visschers, S., Astray Uceda, B., Šípková, A., Wilhelm, K., and De Kock, T.: Black Crusts as Geochemical Archives: Preliminary Results from Antwerp, Belgium, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4340, https://doi.org/10.5194/egusphere-egu24-4340, 2024.

Lake Tana is the largest lake in Ethiopia and the source of the Blue Nile. The lake is protected as a natural heritage site. It is surrounded by wetlands that provide a sanctuary to a diverse set of flora and fauna some of which are endemic to the region. It is also a culturally significant area. Surrounding the lake and on the islands are found tens of stone built monasteries, churches, bridges and palaces built in the Gondarine period (17^th and 18^th Century AD) and earlier. However, these buildings are subjected to biological growth in many different types that cause  discoloration and  degradation. The short and intense rainy season contributes to the nature, diversity and intensity of biological colonization of these stone structures. Biofilms, fungi, mosses, lichen and higher plants can be observed, while also small animals such as mites and rodents are agents of bio-deteriorative process. While micro-organisms alter the visual appearance, roots of higher plants are responsible for more severe physical decay on the site and building level, increasing also the impact of moisture-related weathering in decayed locations. However, micro-organisms can also alter the surface properties of materials, like water absorption and retention, and it is currently not well understood to what extend these contribute to the observed forms of degradation, like chipping, fissuring, cracking, etc. 

This poster aims to address some of the key challenges of managing cultural heritage sites found in a complex, evolving and vulnerable ecosystem, i.e. Lake Tana. Factors such as intense rainfall, humidity, the state of the structures, intensification of agriculture and the perspectives of local communities and stakeholders will be evaluated.

How to cite: Demssie, A., De Kock, T., Ortega-Saez, N., and Gemeda, B.: Biodeterioration of historical buildings and sites in north of Lake Tana, Ethiopia: a preliminary investigation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7547, https://doi.org/10.5194/egusphere-egu24-7547, 2024.

Extreme weather events due to climate change not only affect nature, but can also impact historical buildings, collections, and historic parks and gardens. Assessing the extent to which cultural heritage is threatened by such weather and climate events is an interdisciplinary task that requires the collaboration of experts from heritage preservation and restoration, climate research, natural and engineering sciences, social and economic sciences, landscape architecture, informatics, and more.

Due to this complexity and the abundance of available information, modern IT tools are crucial in explaining the condition of cultural heritage sites to decision-makers and providing insights into future developments. To get a better understanding of the situation of historic parks and gardens, a knowledge platform can offer map-based visualization of data. The biggest challenge in developing such a platform was the integration and processing of relevant data. Due to the interdisciplinary nature of the field and the heterogeneity of the data, it was designed to be able to flexibly integrate and process various types of data. For example, the platform incorporates:

- (Live) sensor data,

- Severe weather risk maps,

- Climate projections and models,

- Expert knowledge incl. tree cadasters,

- Image and video materials, and

- Unstructured documents

This integration aims to provide users with a comprehensive view of their properties.

As part of the project, soil moisture sensors were deployed in Sanssouci Park in Potsdam Germany to monitor soil moisture levels over an extended period of time. These sensors allow for the measurement of soil moisture and temperature at a depth of one meter. A total of 10 sensors were placed at representative locations to provide insights into the irrigation needs of the property. The sensors transmit their data using LoRaWAN (Long Range Wide Area Network), a wireless communication technology that can reliably transmit smaller amounts of data over long distances with low energy consumption. Given the vastness of the Sanssouci Park case study, this approach is suitable as it allows the sensors to be placed in relevant locations without having to consider technical constraints.

The collected data is stored using a FROST server, which is an open-source software project that enables the capture of time series data, including their metadata. The FROST server implements the SensorThings API, a standard of the Open Geospatial Consortium, which aims to standardize the description of sensor data and simplify their reuse. For the visualization of the captured sensor data, a map view has been developed that allows for the positioning of the sensors and the display of their measured data.

How to cite: Moßgraber, J., Hellmund, T., Reuter, J., Kotova, L., and Matheja, K.: Creating a holistic view on the situation of historic parks and gardens, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10672, https://doi.org/10.5194/egusphere-egu24-10672, 2024.

Pollution and climate change raise increasing concerns about the vulnerability of cultural heritage. In carbonate rocks, the primary concern is surface recession, which severely impacts the readability of details, preventing us from transmitting our legacy to future generations. Recession equations available in the literature are highly inadequate due to the complex relationship between climate conditions, hygrothermal (HT) behaviour, and stone textures. This is related to the limited set of parameters used by different authors and to the basic statistical approach used in their fitting processes.

Through this research, we aim to develop a robust and reliable model to predict stone recession, employing Machine Learning algorithms supported by Multivariate Statistical Analysis. We will examine a large database of surface recession measurements obtained from different types of carbonate rocks, which differ in their textural features (e.g. grain size, porosity) and HT behaviour (e.g. water vapour permeability), and of the relative micro-climate conditions under which they have been exposed during outdoor experiments. Additional recession data will be derived from laboratory experiments using an autoclave, allowing precise regulation of pH and temperature of water in contact with stone samples. Validation of the predictive model will involve comparing the recession predictions based on the time series of climate data and material characteristics with the observed recession obtained through the meticulous comparison of historical plaster replicas with the original monuments. This comprehensive analysis aims to ensure the model accuracy in capturing the real-world complexities of carbonate rock surface recession under varying environmental conditions.

Acknowledgement:

ERODEM project was funded by the Department of Geosciences through the “Progetto Premiale” call. This initiative is part of the larger project "Le Geoscienze per lo Sviluppo Sostenibile," funded by the Italian Ministry of University and Research (MUR) within the frame of the “Progetti di Eccellenza 2023-2027”.

How to cite: Mazzoli, C., Coletti, C., Germinario, L., Maritan, L., Pozzobon, R., Preto, N., and Kraniotis, D.: ERODEM: Exploring Carbonate Rock Recession through Data Fusion of Extensive Experimental Data via Machine Learning, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11004, https://doi.org/10.5194/egusphere-egu24-11004, 2024.

The European project SCORE (Sustainable COnservation and REstoration of built cultural heritage, GA 101007531) deals with a two-way assessment of impacts of the environment on materials and of materials on the environment. Indeed, climate conditions and atmosphere composition determine built cultural heritage (BCH) materials’ behaviour and, at the same time, BCH conservation processes (products and techniques) impact greenhouse gases emissions and then climate change.

The objective of this work is to study the feasibility of recycling old mortars and plasters from an existing building to extract the sand with the aim of reusing it to produce new mortars for the renovation of the built heritage. Old mortars and plasters were mainly made with "natural" sands, generally alluvium and river sands, available near the site. These sources of sand may no longer be available or have become scarce. The use of different sands from the original ones in restoration plasters has consequences on the aesthetic properties of the new plasters applied during the renovation, which often requires the use of additives and dyes. To solve this problem, one possibility is to extract the original sand from deconstruction mortars, taken for example from renovation sites.

We tested the proposed method on a site in Paris. Deconstruction mortars were crushed and the sand was recovered, characterized and used for the formulation of new mortars by adding lime and water. Washing methods with water and acid washing solutions have been tested in order to obtain sands free of debris and lime agglomerates. Citric acid was used because it presents good lime dissolution results and is quite easy to employ in restoration works. Microscopic observations were made to determine the effectiveness of each washing solution. Sands washed only with water show some remains of lime on the grain surfaces whereas washing the grains with citric acid solution (2 %) produces excellent results.

In addition, mortars formulations with different grain size of recycled sands were made. These formulations consist of a mixture of recycled sand, water and an additive lime in equal proportions. Specimens of 4 x 4 x 16 cm were produced and their mechanical properties were measured at 28 days of age. During the maturation time, the samples are kept in an environment with constant humidity and temperature, to optimize the conditions of hydration, carbonation and maturation.

The results obtained show that the mechanical properties of mortars made from recycled sand are acceptable and that these are intrinsically linked to the grain size and quality of the sands. The mechanical properties of mortars formulated with recycled sands of the right grain size are similar to those formulated with commercial natural sand. A large part of the recycled sand, after just washing with water, can be used in the formulation of new mortars with regard to standards and aesthetic properties.

How to cite: Menéndez, B., Yameogo, V., and Ghorbel, E.: Sustainability and cultural heritage conservation: re-use of sand from deconstruction renders, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12505, https://doi.org/10.5194/egusphere-egu24-12505, 2024.

The European project SCORE (Sustainable COnservation and REstoration of built cultural heritage, GA 101007531) deals with a two-way assessment of impacts of the environment on building materials and of materials on the environment. Indeed climate conditions and atmosphere composition determine built cultural heritage (BCH) materials’ behaviour and, at the same time, BCH conservation processes (products and techniques) impact greenhouse gases emissions and eventually climate change.

This contribution presents a characterization of the effects of different climate conditions on several traditional restoration mortars, bricks and calcareous stones. A common strategy plan was designed in order to compare the results of weathering exposition experiments in several location: North of Spain, North-West of France, Denmark and Calakmul Biosphere Reserve in Mexico. Some of the presented results correspond to real conditions experiments started before the common exposition campaign but they will be presented because of their interest.

The exposition support is a frame with a plate surface of 1mx1m, placed at 1m height under two exposure conditions: inclination of 10° and at horizontal position. The exposition frame is oriented facing the predominant wind direction. For comparison we chose to expose two kinds of hydraulic lime mortars from Saint Astier company, bricks from Denmark and Mayan calcareous stone from Campeche area treated with Ca(Zn (OH)₃)₂·2H₂O nanoparticles (CZ) in order to improve their behaviour under the exposure conditions.  Mortar coupons had dimensions of 20 x 10 x  3 cm, while the stone samples ones were 5 x 5 x 3.5 cm. A first set of mortars consisting of two-layer sample was tested with a base of a salt protection mortar and a 1 cm upper layer with a finishing mortar. A second set of mortars consists of a monolayer of a masonry restoration mortar. In each specific site, local or recipe mortars have been also exposed. 

Samples have been characterized before exposition and at regular time intervals during the exposition period, that is not finished. Weight, hardness, deterioration patterns, colour and P wave velocity have been measured at different sample locations. Results indicate that in French locations commercial mortars become better than home-made ones, probably due to the absence of any additive in the home-made recipes. First results for the Spanish exposition site show that velocity measurements start detecting some points where layers begin to separate from each other. Some microcracks start to develop at the surface of one type of mortar respecting the monolayer one.  Finally colour changes have been detected in the two layers masonry mortar.

Such gradual (also visible) degradation has previously also been documented in laboratory examination of fired clay bricks submerged in liquids with varying pH (3,5,7,9,11) and varying duration up to more than one year (432 days). Increasing submersion duration resulted in increased degradation, whereas the different pH values representing exposure to various conditions (acid rain, traditional rain, connection with alkaline mortar) revealed different degradation patterns.

The stone coupons improve some of their properties due to CZ addition at initial periods, but they tend to decrease over time.

How to cite: Valdeon, L., Menendez, B., Reyes, J., and Rörig-Dalgaard, I.: Durability of Built Cultural Heritage Materials under different climate conditions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13376, https://doi.org/10.5194/egusphere-egu24-13376, 2024.

The Greater Kuala Lumpur (Greater KL) region, a pivotal hub of Malaysia's economic growth, confronts a burgeoning challenge amid rapid urbanization. Unprecedentedly, it is vulnerable to seismic reactivation possibilities from the dormant Kuala Lumpur Fault Zone (KLFZ). With a comprehensive integration of geospatial technologies, to dissect the geological intricacies of the KLFZ and assess the vulnerability of critical infrastructure within Greater KL. The research aims to bridge the realms of geology and infrastructure engineering, providing actionable insights for policy decisions and urban planning to enhance the region's resilience to seismic events. The problem statement underscores the urgent need for a comprehensive investigation into the interplay between the geological characteristics of the KLFZ and the vulnerabilities in infrastructure. Despite the economic significance of Greater KL, a notable research gap hinders effective mitigation and preparedness strategies. The aim is to unravel the distinctive features of the KLFZ, assess infrastructure vulnerability, and inform policies for safeguarding against potential seismic threats. The methodology unfolds systematically, employing geospatial analysis, remote sensing, and geological data. The research adopts a meticulous data acquisition approach, integrating Sentinel-2 imagery and a seismotectonic map of Malaysia to delineate the fault zone. The extraction of critical infrastructure is conducted with precision, considering the guidelines from the U.S. Cybersecurity and Infrastructure Security Agency. The subsequent steps involve buffer zone creation, overlay analysis, and data classification to develop a vulnerability index. The expected outcome revolves around a comprehensive understanding of the KLFZ and its implications on infrastructure vulnerability. The methodology employs detailed mapping and geospatial analysis, providing insights into fault characteristics, seismic hazards, and critical infrastructure susceptibility. The research aims to contribute a robust foundation for disaster preparedness, urban planning, and engineering strategies, fostering the safety and stability of Greater KL against seismic risks. This research contributes to the broader discourse on urban resilience and disaster management, emphasizing the significance of geomatics in addressing the complex challenges posed by active fault zones or the possibilities of reactivated fault zones. The findings hold practical implications for policymakers, urban planners, and geospatial professionals, offering a nuanced perspective on the intricate relationship between geological factors and infrastructure vulnerabilities in dynamic urban landscapes. In conclusion, this research endeavours to unravel an inform evidence-based decision-making, contributing to the sustainable development and safety of the Greater KL region.

How to cite: Abu Bakar, R., Noorazri, N. F., Mohamad, Z., Sari, A. M., and Ramli, Z.: Vulnerability Index of Critical Infrastructure in Greater Kuala Lumpur Fault Zone, Malaysia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13920, https://doi.org/10.5194/egusphere-egu24-13920, 2024.

The Theban Mountain, on the west bank of the river Nile, near Luxor is internationally known as the burial site of Egyptian Dynasties. The current study focuses on four tombs dating back to the late Old Kingdom and the First Intermediate Period. The tombs are located on the hill's southern slope and were cut into the rock. Their geometry is characteristic since at least six horizontal rows were excavated above one another. Sedimentary rocks of the study area form parts of Tarawan Cretaceous, Esna Shale and Theba Limestone formations. All four tombs were once lavishly decorated with wall paintings and reliefs carved directly into the carbonatic rocks. Until now, these structures have gone through considerable erosion in addition to the occurring damages resulting from their reuse as modern habitations until the late 20^th century. Thus, most of the tombs’ decorations have perished or heavily deteriorated. Since 1983 a Hungarian Archaeological Mission has been exploring the site. Numerous attempts have been made to reconstruct the fragmented walls and conserve the remaining works of art, however, very little effort has been made to understand the deterioration process and its origins. This research describes the geological conditions, petrology and sedimentology of local carbonates, fracture pattern, micro-climatic conditions of the tombs, and decay forms. Stratification, micro-cracking and discontinuities were also mapped. The painted and carved surfaces were documented, and the condition of the walls was assessed. On-site tests included moisture content measurements (vertical profiling) and the detection of surface strength by non-destructive methods. Sensors were placed at various parts of the tombs, recording temperature and relative humidity. The main trigger mechanisms of deterioration processes were identified and preservation measures were made. This study aims to provide an example that helps assess the conditions of rock-cut tombs in arid climates and the changes linked to micro-climatic conditions.

How to cite: Török, Á. and Zomborácz, T.: Condition assessment of limestone tombs Theban Necropolis (Luxor, Egypt), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15733, https://doi.org/10.5194/egusphere-egu24-15733, 2024.

Ongoing urbanization has increased the impact of the urban heat island effect, air pollution, and noise pollution while limiting the space for green areas. Therefore an urgent action is required to mitigate these environmental risks. Vertical Greenery (VG) has emerged as a sustainable and viable solution across diverse contexts, but it is generally not always accepted for historic buildings by experts. The scepticism is rooted in concerns about the potential adverse effects on conservation practices and heritage values. Contrary to expert concerns, VG on historic buildings is seen as a response to reducing the urban heat island effect in high environmental risk areas by the users.

We conducted a comprehensive study in Antwerp (Belgium), a city actively advocating for VG solutions. We selected three neighbourhoods, namely Historical Centre, Oud Berchem, and Borgerhout Intra Muros Zuid, where air pollution, noise, and heat stress are above the risk level. We documented the VG implementations in these three neighbourhoods through the use of GIS and field survey methods. The prevalence of VG in case sites was analysed based on factors such as the heritage status of buildings and the morphology of streets, which could pose challenges to the implementation of VG.

The results suggest that VG is present in up to 14% of all buildings in the selected neighbourhoods. While in the Historical Centre, 59% of the buildings with VG have a heritage designation. As such, narrow streets and heritage designation do not prevent VG implementation in densely built neighbourhoods with green space deficits.

While this study provides site-specific results, the analysis methods we used can guide policymakers and urban planners to explore VG's adaptability to historic buildings in the development of effective integration strategies.

How to cite: Kale, E., De Groeve, M., Pinnel, L., Erkan, Y., Hacıgüzeller, P., Orr, S. A., and De Kock, T.: Mapping Vertical Greenery on Historic Buildings in Neighbourhoods with High Environmental Risks: A Case Study in Antwerp, Belgium, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15931, https://doi.org/10.5194/egusphere-egu24-15931, 2024.

Built heritage is a vital component of urban environments and is rich in cultural and economic values. These buildings are abundant in city centres and have been the site of development for several centuries. They have created dense urban environments, exhibiting strong urban heat island effects. Ground-based vertical greening is a widely used green initiative in dense urban environments to mitigate the current climate stressors due to its small footprint and its ability to cover a large surface area with vegetation. The impact of this green initiative on the materials and structural integrity of built heritage is currently poorly understood and thus the focus of this research.

Several studies have already proven the efficacy of ground-based vertical greening in fostering a more stabilized condition on the underlying wall surface, characterized by reducing the amplitude of temperature and relative humidity fluctuations and the amount of solar irradiation. More stable conditions can imply a lower risk of common degradation processes, such as freeze-thaw weathering and salt crystallization, in historic building materials. 

Since the extent of the vertical greening performance and the deterioration of building façades strongly depend on the orientation of the façade, part of this research aims to establish a relationship between those two variables while considering the orientation of a building façade. Monitoring case studies in the historic city centre of Antwerp during summer develops an understanding of the shading performances of vertical greening and characterises the boundary conditions, such as orientation or leaf area index (LAI), that signify the extent of efficacy. The current case studies reveal a positive correlation between the LAI and the shading potential of vertical greening and highlight the significant role of orientation in mitigating the environmental parameters on the wall surface, as the cooling processes of vegetation mainly depend on the amount of solar irradiation. More specifically, the highest leaf area index and a south or west orientation show us the most significant cooling behaviour during the day which can reduce the risk of salt crystallization the most. The shading performance of vertical greening is only one of the several mechanisms determining the impact of vertical greening on the local environment and the subjected historic materials. 

How to cite: De Groeve, M., Kale, E., Orr, S. A., and De Kock, T.: The influence of orientation and leaf area indices of a vertical green wall on historic building materials, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16698, https://doi.org/10.5194/egusphere-egu24-16698, 2024.

The increase in demand for natural resources due to the growth of the world population is generating an unprecedented increase in waste, and the unsustainability of this situation has induced the change towards a more environmentally friendly economy, the so-called “Green Economy”. Through the new policies for waste management, its reuse in other industrial processes is being encouraged, favouring “Zero Waste” initiatives. This aims to minimize the emission of greenhouse gases that could accelerate climate change, as well as to the reduction of associated energy expenditure. In Spain, two of the sectors that generate the most waste are construction and agriculture, especially linked to animal by-products not intended for human consumption (SANDACH, by its Spanish acronym). In line with these new trends, new initiatives are required to promote the reuse of this waste and the development of more sustainable construction products that involve the reduction of the carbon footprint. Therefore, the main goal of this work is to better understand the effect of adding natural fibres of animal origin, in this case cow hair and pig bristles, to lime mortars for their use both in modern construction and its application in repair historical mortars. In this way, we aim to achieve a double goal: on the one hand, to obtain information about the quality of the result of combining these products; and on the other hand, to reduce CO₂ production by avoiding the incineration of animal by-products not usable in other sectors, finally producing a more sustainable mortar. The specific objectives proposed are: 1) to compare the quality of lime mortars considering the addition of hairs, bristles or with combined proportions of both fibres, with respect to control samples without fibres; 2) to evaluate if the speed and degree of carbonation are affected by the addition of fibres; 3) to identify deterioration processes that may reduce the quality of lime mortars due to aging in the laboratory and outdoors; and 4) to establish optimal production and handling conditions in collaboration with regional or national companies interested in the use of this product. To achieve these goals, in this first stage we will present the preliminary results comparing a mortar without fibres as control sample, with 3 sets of samples with different fibre proportions (containing 10 g or 20 g of cow hair or pig hair per 2 kg), as well as a mixture of both types of fibres (5+5 g and 10+10 g per 2 kg). Based on these results, it will be possible to consider the possibility of increasing the quantity of fibres until reaching an acceptable limit of workability and usefulness without compromising the quality of these mortars.

Acknowledgements: This study was financially supported by the Research Project TED2021-132417A-I00 funded by MCIN/AEI /10.13039/501100011033 and by the European Union NextGenerationEU/ PRTR and E. Molina-Piernas acknowledges co‑funding from the European Social Fund (D1113102E3) and Junta de Andalucía.

How to cite: Molina-Piernas, E., Pacheco-Orellana, M. J., Domínguez-Bella, S., Martínez-López, J., and Sánchez-Bellón, Á.: Insight to the effect of adding cow hair and pig bristles to lime mortars: Towards obtaining more sustainable construction products recycling waste animal byproducts., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18747, https://doi.org/10.5194/egusphere-egu24-18747, 2024.

Cultural heritage in Sweden is increasingly at risk from a number of climate change related factors. These include the direct effects of erosion, flooding, landslides, melting permafrost and related threats, but also increasing industrial activity in the Arctic associated with energy production and the extraction of minerals for 'green' technologies. Whilst much of the physical science of climate related threats is well understood, the practical implications at the local and regional level, as well as the hands-on management of these risks has been somewhat neglected. In a recent pilot study we exposed problems in government planning processes, and in particular that even though the general risks and potential consequences are known, Sweden lacks any form of coordinated system for the prioritisation of sites in terms of conservation, protection, documentation or abandonment. On an international level, we also identified a tendency to focus on above ground archaeological remains and high status sites and monuments. Cultural landscapes, preserved organic and palaeoecological archives, and as yet undiscovered sites are, on the other hand, are less frequently studied and often neglected in planning processes.

Many important cultural heritage sites and landscapes are in close proximity to, and potentially impacted by, transport infrastructure. As the climate warms, roads in particular are increasing in number and traffic volume in the northern areas of Scandinavia. In cooperation with the Swedish Transport Administration we developed a prototype GIS system for assisting in the evaluation of climate related threats to sites in close proximity to transport infrastructure. Three areas were investigated in more detail, ranging from temperate coastal to sub-Arctic rural settings and including a broad variety of cultural heritage types from prehistoric to historical. Case studies looked at particular secondary risks, including the expanding use road salt, and the use of specific datasets (e.g. historical maps, erosion models). This work exposed not only the potential for using such a system in research and planning, but also a number of issues in the uncritical use of publicly available national databases for transport infrastructure, climate threats, and cultural heritage. For example, the poor spatial resolution of risk maps in the Arctic and the poor locational accuracy of many older archaeological and historical investigations can lead to an incorrect assessment of threats. Similarly, much of the rural north of Sweden is poorly surveyed, and existing predictive models for locating unknown sites are inadequate. There is thus a potential bias between risk assessment in the south and the north, and between urban and rural areas. A clear potential exists for the further development of GIS based models with a greater capacity for visualizing and, to an extent compensating for, variability in the quality of the underlying data.

This presentation will show some results and conclusions from these studies, as well as some preliminary findings from ongoing research into the reasons behind problems of implementing strategies for the prioritisation of cultural heritage threatened by future climate change.

How to cite: Buckland, P. and Antonson, H.: Challenges and potential for predicting and managing climate threats to cultural heritage in Sweden, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18769, https://doi.org/10.5194/egusphere-egu24-18769, 2024.

Treatments intending to prevent stone damage sometimes accelerate deterioration unexpectedly. It would be meaningless if the use of protective agents in a more severe deterioration than originally intended. A combination of the properties between agents and stones determines the ability of protective agents to penetrate the stone. In particular, it is expected to depend on the pore diameter distribution of the stone. The present study focuses on freeze-thaw and salt weathering tests were carried out by using several types of tuffs to verify this. The stone materials used were Oya tuff, Nikka tuff, Tatsuyama tuff, Ashino tuff, and Towada tuff, which have different pore size distributions, different strengths, and different durability to salt weathering. In rocks with a high proportion of micro-pores and low resistance to salt weathering, the use of protective agents (water repellents) can delay the onset of surface deterioration. On the other hand, rocks with a high proportion of large pores (>10^0.5 µm) and not less resistant to salt weathering were found to be more likely to deteriorate more severely with an earlier onset of surface deterioration than untreated stones. It is considered to be because the salts crystallize at greater depths when protective agents are applied, whereas they crystallize only at the surface in the case of untreated rocks, and the crystalline pressure causes fracture from the deeper layers. Therefore, when using protective agents, it is necessary to understand the combination of rock properties such as rock structure, pore size, and strength of the rock sample with crystal pressure.

How to cite: Oguchi, C. and Ikeda, Y.: Effect of pore size distribution on the application of water repellent for preventing deterioration of stone materials., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19171, https://doi.org/10.5194/egusphere-egu24-19171, 2024.

Identifying and determining buried archaeological structure limits are crucial for archaeological prospection surveys. The archaeological prospection surveys can shed light on protecting cultural heritage. Magnetic is one of the most applied methods in archaeological surveys to plan the excavation process. It aims to identify buried temples, graves, city walls, and other structures by interpreting the data obtained from magnetic measurements, which is one of the non-destructive geophysical exploration methods. In the process of interpretation of magnetic data, many methods have been developed, such as Horizontal Gradient Magnitude, Analytical Signal, Theta Map, and Tilt Angle methods, which can generate information about the boundaries of potential subsurface features. By analyzing the gradients of the magnetic field data, inferences can be made to determine the edges of subsurface potential archeological structure distributions.

The Olympos is an important ancient city in Antalya (the south of Turkey) and contains many structures from the Byzantine period. This research aims to detect the pipe drain as a water system of the Episkopeion region in the Olympos ancient city. To this end, Tilt Angle (TA) and Edge detection field (ED) methods were tested on the magnetic map of the synthetic model. The horizontal boundaries of the potential pipe drain elements of the region were analyzed by applying the same procedures on the magnetic map obtained from the magnetic measurements on the area that has not been excavated in the Episkopeion archaeological excavation area. Magnetic measurements were carried out in 4 different regions within the Episkopeion area, and each area was numbered and analyzed separately. Combining the results obtained, an integrated visualization of the water system in the area was achieved.

Keywords: Archaeological Prospection, Edge Detection, Olympos, Tilt, Angle, Pipe drains.

How to cite: Deniz Toktay, H.: Edge detection of magnetic data: Preliminary results of application to Episkopeion region in Olympos Ancient City (Antalya), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19203, https://doi.org/10.5194/egusphere-egu24-19203, 2024.

Water scarcity due to climate change and increased water demands is driving the use of non-conventional water sources, including reclaimed water, particularly in agriculture. In many EU countries affected by droughts, reclaimed water has become an important component of the overall water mix. For example, in Spain, Europe’s most arid country, reclaimed water is 560 hm³/year (nearly 10% of the treated wastewater).

The use of reclaimed water has many advantages, but it also faces significant barriers. The lack of social acceptance has been described as one of the major obstacles. However, understanding how different stakeholders perceive the use of reclaimed water has not been addressed in depth the literature so far. Existing studies are scarce and fragmented. They focus on a single type of stakeholder (farmers or consumers), ignoring the perceptions and eventual acceptance of different stakeholder groups directly or indirectly impacted by reclaimed water.

This study attempts to fill this gap by exploring the plurality of perspectives on the use of reclaimed water for irrigation in Spain. To do so, we applied Q-methodology and conducted twenty-three interviews with key stakeholders, including representatives of public administration, environmental groups, farmer associations, food retailers, consumer organizations, water treatment companies and water reuse experts. As part of the Q study, stakeholders were asked to sort according to their level of relative agreement 36 statements related to different socio-economic, technical, environmental, institutional and political aspects of reclaimed water. The results were analysed using principal component analysis in R ('qmethod' package).

Our study found three discourses: 1- Reclaimed water is a guarantee for water supply in agriculture, 2- Reclaimed water has the potential to be a sustainable water resource and 3- Reclaimed water has a negative impact on the environment. These discourses show different ways of understanding reclaimed water. Although stakeholders had diverse perceptions, there is a certain agreement that the public administration has the will to promote the use of reclaimed water and therefore it is key to promote reclamation projects in agriculture.

They also agree that most consumers are not informed about the quality of reclaimed water and its benefits in the agricultural sector, which leads to a certain social reluctance to use it, and to avoid this, awareness campaigns would be necessary to increase the social acceptance of reclaimed water.

Therefore, some discourses conclude that it is possible that reclaimed water may have pollution problems, but it is also true that the potential for improvement in reclamation technology can avoid them. Regarding the reduction of ecological flows, it is important to study this on a case-by-case basis, as this problem tends to occur in inland areas, although not always.

Finally, the question of who should pay for water regeneration is very controversial and the best solution is to share the costs between the different stakeholders, with the purification and reclamation being carried out tipping fee, and the farmers, with the help of the administration, bearing the costs of the infrastructure and controls from WWTP.

How to cite: Villacorta Ranera, C., Blanco Gutiérrez, I., and Novo Nunez, P.: Disentangling social perspectives on the use of reclaimed water in agriculture using Q methodology, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-605, https://doi.org/10.5194/egusphere-egu24-605, 2024.

Flex crops—crops with multiple end-uses that can be flexibly interchanged—play an important role in our society. Due to high nutritional and energy contents, they became widely used in various industries, providing food, animal feed, biofuels, and other chemical components. However, a limited number of studies exists on the environmental pressures of such crops, specifically concerning water resources.

Here, we aim to quantify the water footprints of main flex crops—namely maize, oil palm, soya beans, sugar cane, coconut, cassava, rape seed, and sunflower—using a recently published database on gridded water footprints of the world’s major crops in the 1990–2019 period. Our study reveals three key developments:

• All flex crops experienced large water-productivity gains in response to increasing crop yields (less water is needed per tonne).
• The global water footprint of flex crops has increased by more than one trillion cubic metres as productivity gains were insufficient to meet rapidly growing demand.
• The production of flex crops has been concentrating around main exporting regions, most notably in Latin America and South-eastern Asia.

As demand keeps increasing, this raises a need for further research addressing the sustainability of flex crops. In particular, regarding the potential links to green and blue water scarcity, exposure of global supply chains to socio-economic and climatic risks, and the role of flex crops in our society.

How to cite: Mialyk, O., Berger, M., and J. Booij, M.: Increasing water footprints of flex crops, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1342, https://doi.org/10.5194/egusphere-egu24-1342, 2024.

How to cite: Kupfer, N., Montzka, C., and Quoc Vo, T.: Overcoming Barriers to Sustainable Rice Production: A Remote Sensing-Enabled Approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1481, https://doi.org/10.5194/egusphere-egu24-1481, 2024.

Renewable energies (REs) are increasingly important in addressing the challenge of climate change. Their development and widespread use can significantly reduce greenhouse gas emissions from fossil fuels and help mitigate the effects of climate change. To achieve a "net-zero" carbon economy, the transition to a RE system must occur alongside a profound transformation of the agri-food sector. Agrivoltaics (AVs) offers an opportunity to achieve both of these goals simultaneously. AVs provides clean energy and it is an important tool for realizing a sustainable and circular food economy in rural and farming communities. Additionally, by placing photovoltaic (PV) panels over crop fields, AVs can avoid the competition between solar energy and agriculture for land-use. This can also help to mitigate the impact of climate change on crop productivity, which is expected to be negatively affected by a warmer and drier future climate.
In our study, we developed a large-scale sub-grid AVs model to explore the inter-links between climate, the AVs system, and crops. This model enables a comprehensive evaluation of the effectiveness and efficiency of an AVs configuration within the context of the climate-water-energy-food nexus. Our approach involves coupling a PV model with the soil-vegetation-atmosphere-transfer model ORCHIDEE (Organising Carbon and Hydrology In Dynamic Ecosystems) to construct the AVs module. The PV layer simulates the effects of PV panels, altering solar radiation and wind speed taken from atmospheric forcings. Subsequently, these altered variables, along with other key atmospheric variables like air temperature and precipitation required by ORCHIDEE, are used as inputs to the hydro-vegetation layer. Leveraging ORCHIDEE capability to quantify terrestrial water and energy balances at the land surface, this integration allows for a comprehensive simulation of crop ecosystem behavior within an AVs system. Net Primary Production (NPP), Water Use Efficiency (WUE), and PV power potential (PV_pot) are finally computed as ultimate outputs of our model, representing key indicators for the water-energy-food nexus. Focusing on the Iberian Peninsula and the Netherlands, we apply our model to assess three AVs configurations (fix-tilted array, sun tracking, sun antitracking) across three specific years (2015, 2018, 2020) for two types of crops. Specifically, we compare the performance of different configurations among themselves and against the situation without AVs systems to analyze different behaviors depending on climate conditions, crop type, and location and to explore the potential benefits of the AVs systems.

How to cite: Rapella, L., Drobinski, P., and Faranda, D.: Modelling Agrivoltaics in a climate perspective for water-energy-food nexus analysis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1491, https://doi.org/10.5194/egusphere-egu24-1491, 2024.

The escalating threat of water scarcity presents a dual challenge to both food production and water-related systems. The degradation of conventional water resources (e.g., surface water and ground water), coupled with insufficient investment in infrastructure, has compelled the water sector to seek alternative sources such as Non-Conventional Water Resources (NCW), encompassing reclaimed water reuse and desalination of brackish and seawater, as a long-term strategy, particularly in arid and semi-arid environments where irrigation is a vital component.
Recognizing the substantial potential of NCWs, this research presents the outcomes of an extensive study [1]. The study adopts a multidisciplinary approach, specifically employing Multi-Criteria Decision Making (MCDM), to assess the effectiveness of smart city water management strategies within the framework of NCWs. Utilizing representative criteria, our analysis involves objective judgment, assigns weights through the Analytic Hierarchy Process (AHP), and scores strategies based on their adherence to these criteria.
Our findings underscore the pivotal role of the "Effectiveness and Risk Management" criterion, carrying the highest weight at 15.28%, in shaping strategy evaluation and ensuring robustness. Criteria with medium weight include "Resource Efficiency, Equity, and Social Considerations" (10.44%), "Integration with Existing Systems, Technological Feasibility, and Ease of Implementation" (10.10%), and "Environmental Impact" (9.84%), focusing on ecological mitigation. Recognizing the importance of community engagement, "Community Engagement and Public Acceptance" (9.79%) is highlighted, while "Scalability and Adaptability" (9.35%) address the dynamics of changing conditions. Balancing financial and governance concerns are "Return on Investment" (9.07%) and "Regulatory and Policy Alignment" (8.8%). Two low-weight criteria, "Data Reliability" (8.78%) and "Long-Term Sustainability" (8.55%), emphasize data accuracy and sustainability.
Strategies with higher weights, such as "Smart Metering and Monitoring, Demand Management, Behavior Change," and "Smart Irrigation Systems," prove highly effective in enhancing water management in smart cities. Notably, medium-weighted strategies (e.g., "Educational Campaigns and Public Awareness," "Policy and Regulation," "Rainwater Harvesting," "Offshore Floating Photovoltaic Systems," "Collaboration and Partnerships," "Graywater Recycling and Reuse," and "Distributed Water Infrastructure") and low-weighted strategies (e.g., "Water Desalination") also contribute significantly, allowing for customization based on each smart city's unique context.
This research is of significance as it addresses the complexity of urban water resource management, offering a multi-criteria approach that enhances traditional single-focused methods. It comprehensively evaluates water strategies in smart cities and provides a criteria-weight-based resource allocation framework for sustainable decision-making, thereby boosting smart city resilience. It is essential to acknowledge that results may vary depending on specific smart city needs and constraints. Future studies are encouraged to explore factors such as climate change's impact on water management in smart cities and consider alternative MCDM methods like Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) or Elimination and Choice Expressing the Reality (ELECTRE) for strategy evaluation.

[1] Bouramdane, A.-A., Optimal Water Management Strategies: Paving the Way for Sustainability in Smart Cities. Smart Cities 2023, 6, 2849–2882. https://doi.org/10.3390/smartcities6050128

How to cite: Bouramdane, A.-A.: Sustainable Management Strategies for Non-Conventional Water Resources: Enhancing Food and Water Security in Arid and Semi-Arid Regions , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2856, https://doi.org/10.5194/egusphere-egu24-2856, 2024.

Growing pressure on water resources and climate uncertainty are driving the need for alternative water sources. In countries with severe water stress, such as Spain, the reuse of water from urban wastewater treatment plants has become a promising opportunity to secure and improve agricultural production. The use of reclaimed water in agriculture offers many significant economic and the environment benefits. In addition to preserving freshwaters, it increases the reliability of water supplies and provides a source of nutrients needed for crop growth and soil fertility. In recent years, the European Union and the Spanish government have promoted the reuse of reclaimed water for irrigation as part of their circular economy strategies. However, the uptake of this practice is still limited and so far deployed below its potential.

This study uses a hydro-economic model to investigate the potential for reclaimed water reuse in agriculture and effective water resource management in the Western La Mancha aquifer in Spain. In this region, groundwater abstraction for irrigation exceeds aquifer recharge, leading to conflicts between rural socio-economic development and water conservation. In this context, reclaimed water reuse is seen as an alternative source to groundwater that can contribute to reduce over-exploitation. An economic optimization model is linked to the hydrology model WEAP (Water Evaluation And Planning system) to analyse management alternatives, that include full compliance with the current water abstraction regime and different levels of reclaimed water reuse from the region’s urban wastewater treatment plants (current level and full potential). Climate uncertainty is also simulated and represented by projected precipitation and temperature changes from a selection of global climate models under different representative concentration pathways (4.5 and 8.5).

The results show that compliance with the abstraction regime can help to mitigate aquifer overexploitation. Reclaimed water reuse represents an additional effort for aquifer recovery, resulting in improved groundwater storage levels. Its effect is particularly relevant under climate change scenarios, although groundwater levels would show a downward trend. However, reusing reclaimed water for irrigation reduces effluent flows to rivers and has a negative impact on meeting the environmental needs of downstream wetlands. At the same time, water reuse could mitigate the negative impact of water scarcity on farm incomes, especially in municipalities with high-capacity treatment plants (> 1Mm3/year) where high value crops (vineyards, olives and horticultural crops) are grown. 

Overall, this research evidence uneven impacts of reclaimed water reuse across the basin. Its contribution to reversing groundwater depletion is limited and should be understood as part of the solution, but not as the solution itself. Our results provide valuable insights into the economic and environmental implications of reclaimed water reuse and can support policy decisions for the adoption of such alternatives for integrated and sustainable water resource management in semi-arid regions.

How to cite: Esteve, P., Blanco-Gutiérrez, I., Mautner, M. R., Seifollahi-Aghmiuni, S., and Escobar, M.: Challenges and opportunities of using reclaimed water for agricultural irrigation in Spain: A hydro-economic analysis. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3533, https://doi.org/10.5194/egusphere-egu24-3533, 2024.

In a context of growing global water demands, plus climate change affecting water resources availability, non-conventional water sources (like reclaimed water and desalinated seawater) are emerging as promising water supply alternatives. Given that agriculture is the major contributor to water withdrawals, this study analyzes if the use of non-conventional water for irrigation leads to a better performance of irrigation communities (ICs). To do so, the research includes several ICs from the Segura River Basin (southeast of Spain), a region with structural water deficit, which is pioneer regarding the use of non-conventional water; as well as ICs from the Apulia region (southeast of Italy), which also suffers from water scarcity problems, but is less experienced regarding the use of non-conventional water. A benchmarking analysis was carried out, based on a set of Key Performance Indicators (KPIs), such as irrigation efficiency, guarantee of water supply, energy costs or gross margin, among others. This methodology has been previously used in the framework of the water and drainage sector. Also, a Principal Component Analysis and Clustering Analysis were applied to explore potential dissimilarities between the studied ICs and their causes. Finally, a regression analysis was carried out to observe if the use of non-conventional water has any effects on the performance of the studied ICs. The results of this research may help to increase knowledge regarding the pros and cons of using these non-conventional water resources, depending on the socioeconomic, environmental and geographical context. This way, this study would contribute to promoting the use of non-conventional water in other regions, leaning towards a more sustainable use of water resources and, consequently, protecting and preserving water ecosystems.

How to cite: Ballesteros-Olza, M., Stempfle, S., Blanco-Gutiérrez, I., Gómez-Ramos, A., Giannoccaro, G., and De Gennaro, B.: Do non-conventional water resources lead to a better performance of irrigation communities? A comparative analysis between the regions of Murcia (Spain) and Apulia (Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3941, https://doi.org/10.5194/egusphere-egu24-3941, 2024.

The United Kingdom (UK), a high consumer of meat, has traditionally relied heavily on the European Union for its meat imports. However, with the advent of Brexit, the UK now faces the imperative of identifying potential meat-importing nations. The choices of different meat import countries not only impact the economy and environment of the UK but also other countries around the world. This study builds the UK Meat Trade-centred World Input-Output Model (UK-MTWIO), incorporating diverse import data within various scenarios. With different scenarios considering costs, GHG emission and animal welfare, this study analyzes the economic, environmental and animal welfare impacts on the UK and other countries worldwide. The novelty involves the comprehensive consideration of scenario setting, the application of RAS method as well as the animal welfare analysis with the method of world input-output model. The study reveals that beef imports have the most significant impact on the imports of the lamb and pork. Meanwhile, the changes in the UK's meat trade may change the trade partners of some major meat-importing countries. In terms of environment, some import scenarios have the potential to contribute to GHG emissions reduction in the global agricultural sector: CHN, MEX, and JPN are typical countries that are significantly impacted. The results of this study provides valuable insights for policymakers making meat trade decisions post-Brexit.

How to cite: Wang, K., Liu, L., Chenoweth, J., and Morse, S.: The economic and environmental impacts of UK meat imports post-Brexit, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4136, https://doi.org/10.5194/egusphere-egu24-4136, 2024.

China's increasing food consumption, particularly for animal products, presents a substantial challenge to mitigating greenhouse gas (GHG) emissions, not only within China but also extending to its trading partners. In this study, we employ the well-established food system integrated assessment model (GLOBIOM-China) to comprehensively investigate GHG emissions within the context of China's future food consumption. Our study indicates that in the baseline scenario (BAU), GHG emissions from China's food consumption side are projected to be 965 million tonnes of CO₂ equivalent (Mt CO₂ eq) by 2060, similar to the current level. Domestically, ruminant production accounts for a substantial 44% of total consumption-based emissions. Meanwhile, livestock-related methane emissions take prominence in terms of different gas categories, comprising a significant 45%. Virtual GHG emissions import is expected to decrease due to the deceleration of land use change, while the GHG emissions attributable to livestock product imports are projected to incrementally rise, eventually constituting 17.2% of the total food consumption-based emissions. Striving for food self-sufficiency (SS scenario) offers a pathway to diminishing China's food system GHG emissions and virtually imported emissions by 6% and 43%, respectively. However, this scenario presents an increase of domestic emissions by 2% and simultaneously poses challenges to domestic land use and other related indicators. Maintaining basic food self-sufficiency, and reducing calorie intake from animal sources and improving production practices contribute to a 216 Mt CO₂eq reduction of total GHG emissions. This approach not only holds promise for emission reduction but also brings broader benefits such as decreased agricultural commodity prices (by -28%), reduced nitrogen fertilizer uses (by -13%), diminished agricultural land requirement (by -10%), and only 2% decline in per capita calorie intake. Our study reconciles GHG mitigation strategies and food security within China's food system, thereby contributing significantly to global sustainable development.

How to cite: Zhao, H., Zhang, H., Havlik, P., and Chang, J.: Balancing food system greenhouse gas emissions reduction and food security in China, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5637, https://doi.org/10.5194/egusphere-egu24-5637, 2024.

Humanity’s contemporary challenge in achieving global food security is sustainably feeding the rising global population. Intensive agricultural practices have powered green revolutions, helping nations attain self-sufficiency. However, these fertilizer-intensive methods and exploitative trade systems have created unsustainable agrarian systems. To probe the environmental consequences on production hubs, we map the fate of Nitrogen and Phosphorus in India’s interstate staple crop trade over the recent decade. Here, we analysed the spatiotemporal evolution of physical and virtual nutrient flow within India's interstate agricultural trade network, examining the environmental load on key production regions, assessing the sustainability of domestic wheat and rice trade systems in light of nutrient surplus, and providing policy recommendations for environmentally sustainable food security. Our examination of the cereal crop trade reveals that the Nation's food bowls contributing significantly towards domestic food security are sacrificing their environmental goals by becoming pollution-rich and water-poor. Our study emphasises policies focusing on redistributing funds from agricultural subsidies that aggravate environmental disparity to those incentivising sustainable production. The findings could offer a foundation for designing and exploring alternate trade network configurations that aim for environmental sustainability without compromising food security goals.

How to cite: Goyal, S., Dave, R., Bhatia, U., and Kumar, R.: Agricultural pollution in Indian Interstate Trade Network, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7331, https://doi.org/10.5194/egusphere-egu24-7331, 2024.

The surge in pharmaceutical use during global pandemics, like SARS-CoV-2, has led to increased antiviral concentrations in wastewater treatment plant influents. The low biodegradability of certain antivirals poses a challenge for wastewater treatment, threatening aquatic and soil ecosystems. This study aimed to optimize ozonation and catalytic ozonation processes for removing two anti-COVID-19 drugs (namely, favipiravir and oseltamivir) and assess their ecotoxicological effects in the context of potential wastewater reuse.

In this study, samples with 50 µg/L of favipiravir and oseltamivir were added to synthetic wastewater with approximately 50 mg COD/L, mirroring a typical domestic effluent. Experiments involved three ozone doses (0.2, 0.6, and 1 mg O₃/mg DOC) at pH levels of 7 and 10. Adding 0.1 g/L of ZnFe layered double hydroxide as a catalyst aimed to improve the ozonation efficiency. Samples with 0.1 mg/L polyethylene microplastics were prepared to explore the efficiency of the applied processes in the presence of microplastics. The target drugs were quantified by LC-MS/MS. E. crypticus was used to understand the ecotoxicological impact of the treatment techniques on the potential reuse of treated wastewater for irrigation.

Regardless of the ozone dose used, ozonation at pH=7 resulted in removal efficiencies of 84% and 64% for favipiravir and oseltamivir, respectively. Increasing the pH value to 10 did not improve favipiravir elimination, yet an additional removal of 21% was recorded for oseltamivir at all three ozone doses. During catalytic ozonation, an approximately 30% decline in the abatement of drugs was observed when compared with ozonation alone, which could be attributed to either adsorption of ozone on the catalyst’s active-sites (blockage of active-sites and reduction in the availability of ozone radicals) or production of refractory by-products (enhancement in the competition between radicals and active-sites). In the presence of microplastics, ozonation experiments at pH=7 provided an average decrease of about 30% in the removal efficiency for both drugs whereas ozonation at pH of 10 resulted in an approximately 15% fall in the elimination level. Catalytic ozonation in the absence of microplastics, however, showed positive effects on the reduction rates of the examined drugs since the applied process yielded an improvement in the abatement of 14 and 7% for favipiravir and oseltamivir, respectively. Both in the presence and absence of microplastics, ozonation and catalytic ozonation of antivirals at pH=7 did not lead to any toxic effects for the reproduction of E. crypticus; instead, an increase in the reproduction performance was found, possibly due to the formation of more biodegradable organic intermediates. The experimental data obtained revealed that ozonation or catalytic ozonation could be viable alternatives for upgrading the existing wastewater treatment plants as they functioned well as a complementary treatment process not only to reduce the release of antivirals from domestic effluents, but also to substantially increase the reuse potential of treated wastewater for irrigation purposes.

This study was financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK, Project #121Y383) and Scientific Research Projects Coordination Unit of Istanbul Technical University (ITU-BAP, Project # MYL-2023-44496).

How to cite: Chavoshi, N., Dogruel, S., Bilgin-Saritas, N., Karaoglu, Z., Ozturk-Ufuk, I., Keyikoglu, R., Khataee, A., Topuz, E., and Pehlivanoglu-Mantas, E.: Removal of favipiravir and oseltamivir in domestic wastewater effluents using ozonation and catalytic ozonation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7380, https://doi.org/10.5194/egusphere-egu24-7380, 2024.

As urban populations swell and infrastructure demands escalate, managing resources sustainably becomes increasingly challenging. This paper focuses on the energy challenges inherent in distributed water management systems, using sewer mining as an example. Sewer mining is a distributed water management solution involving mobile wastewater treatment units that extract and treat wastewater locally. In this context, we examine the integration of renewable energy sources, specifically solar photovoltaics, to reduce reliance on traditional power grids, highlighting a pilot implementation at the Athens Plant Nursery in Greece since 2021. The study evaluates various system configurations, balancing performance with landscape integration, to propose a scalable and robust model for distributed water management. This approach not only addresses the direct energy requirements of water treatment systems but also contributes to the broader agenda of circular economy, by enhancing the sustainability and resilience of urban water infrastructure.

This work is supported by IMPETUS research project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 101037084

How to cite: Zisos, A., Monokrousou, K., Tsimnadis, K., Dafnos, I., Dimitrou, K., Efstratiadis, A., and Makropoulos, C.: Leveraging renewable energy solutions for distributed urban water management: The case of sewer mining, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7458, https://doi.org/10.5194/egusphere-egu24-7458, 2024.

Water and food security in the Indo-Gangetic Plain (IGP) is severely affected due to the intensive irrigated agriculture, growing population, and changing climate. Agricultural intensification with the water-intensive rice-wheat system has increased the water demand in India. The declining monsoon rainfall and increased irrigation with more reliance on groundwater sources have resulted in groundwater depletion over India’s fertile region, the Indo-Gangetic Plain (IGP), with high energy usage. Despite several agricultural technology developments, no improvement is found in calorie production from cereal crops per unit of water consumption in the IGP. Crop switching from water-intensive rice and wheat to climate-resilient nutri-cereals can be a potential solution for water sustainability, but other dimensions i.e. food supply, and farmers’ profit need to be considered for implementation. So, a multi-objective optimization framework is needed to address the social, economic, and environmental sustainability objectives which are conflicting in nature, to find the optimal cropping pattern. In this study, an optimization model is developed and applied for crop switching with objectives to maximize calorie production, and farmers’ profit and to minimize water consumption by reallocating the cropped areas between cereals at the district level. Application of the model suggests switching from rice to millet and sorghum in the Kharif Season (monsoon), and wheat to sorghum and barley in the Rabi season (winter), which could potentially decrease water consumption by 32%, increase calorie production by 39%, and elevate farmers' profits by 140%. Water and energy savings (with the replaced cropping pattern are higher than changing irrigation practices (i.e. from flood to drip). So, crop switching coupled with efficient irrigation practices (drip) contributes to saving more energy and water. These findings suggest the potential of crop switching to address the multidimensional sustainability challenges in agricultural practices in the IGP, with a scope of application to other regions grappling with similar issues. The implementation of crop switching is driven by multiple factors such as the willingness of farmers, incentives, and other strategies for farmers to shift crop practice, procurement of nutri cereals through Minimum Support Price, subsidized supply through the Public Distribution System, and consumer demand; thus, leaving an opportunity to explore these aspects in future studies for policy framing towards sustainable agricultural practices.

How to cite: Chakraborti, R., Davis, K. F., DeFries, R., D. Rao, N., Joseph, J., and Ghosh, S.: Crop switching in the Indo-Gangetic Plain of India can improve water and food sustainability with increased farmers’ profit, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7880, https://doi.org/10.5194/egusphere-egu24-7880, 2024.

Soil hydrophysical properties can be very spatially and temporally heterogeneous even in small areas. Due to this spatial and temporal variability, it is impossible to obtain real data for each point of interest. Therefore, the possibility to obtain the optimal estimated value, at any desired point, is decisive. The aim is to evaluate different methods to minimise the error made in this measurement.

Two basins were selected in the Autonomous Community of Madrid (Spain), where hydraulic conductivity data were taken at different points. All sampling point in both basins were georeferenced. For each basing different interpolation methods were tested. The methods used are Spline, Inverse Distance Weighted Interpolation (IDW), Kriging, and Thiessen Polygons. With the help of the Matlab program, the values for each method were obtained. Finally, the error is used for the analysis.

Differences among the obtained data by each method are expected to be found. In addition to the differences between the number of samples and the error, and the location in the basin of the samples.

In conclusion, it is hoped to find the most appropriate method for obtaining a value as close to reality as possible. Furthermore, it is expected to be able to use this methodology in other situations.

Acknowledgements: This research Project has been funded by the Comunidad de Madrid through the call Research Grants for Young Investigators from Universidad Politécnica de Madrid

How to cite: Cuevas, B., Pascual, E., Bernal, C., and Zubelzu, S.: Comparison of different interpolation techniques for sub-basins located in Madrid., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9881, https://doi.org/10.5194/egusphere-egu24-9881, 2024.

Small tropical islands in the Pacific Ocean are highly vulnerable to climate change. Nature-based solutions can help local communities adapt their local agricultural systems. Through a comparative analysis, we evaluated the effects of agroforestry management practices on soil temperature, soil water availability and storage, and carbon stocks in Santa Cruz Island (Galapagos Archipelago). We installed six monitoring sites that consist of two replicates per agroforestry management practices: (i) conservation of native forest, (ii) traditional agroforestry, and (iii) abandoned farmland in passive restoration. After pedological characterization of the sites, the soil physicochemical and hydrological properties were determined in the laboratory. Over 30 months (July 2019 to December 2021), the environmental sensors captured the hydrometeorological and soil physical and hydrological properties of the sites. This was done by a dense network of rain gauges, air temperature and relative humidity sensors, and time-domain reflectance probes that registered volumetric water content and soil temperature.

We measured differences in soil temperature, moisture availability and soil organic carbon content between soils under forest, traditional agroforestry and passive restoration. Forest soils are protected from direct solar radiation, and trees keep the soil 12% cooler than soils converted to agricultural land. Soil moisture is 20% higher under forest than under traditional agroforestry or abandoned farmland, and forest soils have a lower dry bulk density, lower saturated hydraulic conductivity and higher water retention capacity. The forests and sites under passive restoration store more than 377 Mg C. ha^-1 (1 m depth), about 50% more than under traditional agroforestry. The study shows that conserving forest patches in an agricultural landscape might be a promising strategy to mitigate increasing soil temperatures, agricultural drought, and decline in soil organic carbon content. However, more studies on landscape scale are needed to corroborate those results.

How to cite: Alomia, I., Montes, Y., Paque, R., Dixon, J., Molina, A., and Vanacker, V.: Agroforestry management practices as nature-based solutions for climate change adaptation in the Galapagos Islands, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11353, https://doi.org/10.5194/egusphere-egu24-11353, 2024.

Sand dams are water harvesting structures built across ephemeral sandy rivers to increase water supply in drylands. Despite their effectiveness in reducing water scarcity for local communities and their recent traction in research and development, information on their distribution and characteristics are sporadic and largely unreported. This gap represents a major barrier for understanding the large-scale potential of such a Nature-based Solution for drylands and planning for new infrastructure. This paper presents a global database of sand dam locations and dimensions developed within a collaboration between research and development experts on the topic. We collected sand dam information on location from several sources, ranging from research reports to databases provided by practitioners. We then reviewed and enriched them based on visual inspection from Google Earth images. The georeferenced information provided by the database can support research development on the effectiveness of sand dams and support practitioners with science-based criteria for sand dam development across global drylands.

How to cite: Eisma, J., Piemontese, L., Castelli, G., Quinn, R., Mpofu, B., Graber Neufeld, D., Ryan, C., Ritchie, H., Villani, L., and Bresci, E.: Expert-based global database of sand dams dimensions and distribution across drylands, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11369, https://doi.org/10.5194/egusphere-egu24-11369, 2024.

Pumping energy is a key component of the groundwater governance challenge. Yet it is largely missing in the discourse on agricultural use of groundwater. A sub-category of literature studying groundwater-energy nexus tends to focus on groundwater depletion hotspots where entrenched interests and long-standing history restrict the range of feasible energy models. We simulate expected impacts of expanding groundwater irrigation under five different energy provision models in a region with among the lowest irrigation coverage, and therefore, free of path dependent policies. We find aquifer properties play a crucial role in mediating the groundwater-energy nexus. On average, the maximum volume of water that can be pumped from a well of a specific depth in an alluvial aquifer is approximately 150 times the volume that can be pumped from a well in a hard-rock aquifer. Therefore, managing uncertainty in groundwater consumption is a far greater challenge in alluvial than hard-rock aquifers. Uncertainty in groundwater consumption can be limited in hard-rock aquifers if the number of wells and depths of wells can be controlled - capital subsidies for well construction could be a potential policy. Our results imply that while solar pumps are a risky alternative in alluvial aquifers for maintaining current and future groundwater levels, they are relatively safe and among the most economical for expanding irrigation in hard-rock regions. Using a novel dataset comprising of biophysical and socioeconomic data, we find hard-rock regions to have limited irrigation coverage, high availability of annually replenishable groundwater, and high concentrations of marginalized farmers. Therefore, groundwater irrigation expansion in hard-rock areas could have dual benefits of ensuring future food security and targeting poverty reduction.

How to cite: Ray, S.: Balancing groundwater access and sustainability through energy pricing in India, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13972, https://doi.org/10.5194/egusphere-egu24-13972, 2024.

Within the European Union, approximately 129 Mtons of food waste were generated in 2011, and about 52% of them derived from post-processing activities. The most common by-products originated from the food industry are spent coffee grounds, sugar cane waste, and fruit peels, while the main agricultural wastes are livestock slurry, manure, crop residue, and woodland pruning and maintenance wastes. The olive tree is cultivated worldwide, and more than 90% of the cultivated area is located in the Mediterranean basin. The olive oil extraction is carried out using two- or three-phase centrifuge systems. The olive mill wastes can be incorporated into the diets of productive animals, especially ruminants, due to their high fiber content. The aim of this work was to investigate the optimum conditions for silage production for animal food using olive oil wastes from a diphasic olive mill facility. Olive mill waste and straw were the base materials for silage composition: 53 to 55% and 45 to 47%, respectively (dry weight basis). Different mass ratios of molasse (0 to 4%) and urea (0 to 1%) per olive mill mass (dry weight) were used. The presence of urea and the absence of molasses turned out to be inhibitory factors for the silage process. The highest molasses rates the highest efficiency of silage production.

How to cite: Manariotis, I., Biliani, S., Manarioti, M. V., and Athanassolpoulos, N.: Silage  production from olive mil wastes , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14721, https://doi.org/10.5194/egusphere-egu24-14721, 2024.

How much and what we eat and where it is produced can create huge differences in greenhouse gas emissions. Bridging food consumption with detailed household-expenditure data, this study estimates dietary emissions from 13 food categories consumed by 201 expenditure groups in 139 countries, and further models the emission mitigation potential of worldwide adoption of the EAT–Lancet planetary health diet. We find that the consumption of groups with higher expenditures generally creates larger dietary emissions due to excessive red meat and dairy intake. As countries develop, the disparities in both emission volumes and patterns among expenditure groups tend to decrease. Global dietary emissions would fall by 17% if all countries adopted the planetary health diet, primarily attributed to decreased red meat and grains, despite a substantial increase in emissions related to increased consumption of legumes and nuts. The wealthiest populations in developed and rapidly developing countries have greater potential to reduce emissions through diet shifts, while the bottom and lower-middle populations from developing countries would cause a considerable emission increase to reach the planetary health diet. Our findings highlight the opportunities and challenges to combat climate change and reduce food inequality through shifting to healthier diets.

How to cite: Li, Y., He, P., Shan, Y., Li, Y., Hang, Y., Shao, S., Ruzzenenti, F., and Hubacek, K.: Reducing climate change impacts and inequality of the global food system through diet shifts, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14983, https://doi.org/10.5194/egusphere-egu24-14983, 2024.

Food insecurity results from a complex interplay of climate, socio-economic and political drivers, with local food security being frequently influenced by events elsewhere. Recent unprecedented climate events and economic disruptions such as Covid-19 and the resurgence of large intra- and inter-state conflict, show the diverse and unpredictable nature of risk, which can suddenly impacting food production and supply chains.

Here, we present a coupled hydrology-crop production-trade model that is able to simulate, in real time, current and near-future risks to water and food security. The model combines an operational process-based simulation of global crop production and hydrology with an ML-powered trade module, trained on FAOs detailed trade matrix dataset. It is updated monthly with the latest ERA5 climate data from the Copernicus Data Store to assess current risk, and can be forced with seasonal forecasting and long term climate projections up to 2100. The model explains about 50% of yield variability in major growing regions - a critical characteristic for nowcasts or seasonal forecasts – and the majority of food trade and trends therein, but generally still underestimates the variability. As a first step to better reproduce observed crop yield anomalies we improved the simulation of growing seasons in the production model.  

By combining production with trade, we are able to estimate the impact of climate-related yield anomalies elsewhere, and to assess risks for water- and food security at the country, regional or global scale. Derived indicators provide a real-time insight into, for example, food production and storage per capita, crop water productivity, or crop or export specific water stress. Through continued evaluation and learning, we expect to be able to better identify emerging stresses in the food system and its drivers, and support early anticipation of potential future food security risks. This should ultimately lead to a better understanding of the complexity of the global food system and eventually result in a more sustainable food system.

How to cite: Gülpen, M., Siderius, C., van der Velde, Y., Cranko Page, J., Biermann, J., Hutjes, R., Nauta, L., Sutanto, S., and Biemans, H.: Tracking real-time impacts of climate variability and trade disruptions on water and food security , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15307, https://doi.org/10.5194/egusphere-egu24-15307, 2024.

The Green Revolution in India, from 1967-68 to 1977-78, led to a significant shift in the country's agricultural landscape, transforming it from an insufficient food production country to a global agricultural power. This led to an increase in the use of pesticides, such as atrazine, which can pollute water sources and endanger aquatic habitats. This research aims to find sustainable and practical techniques for atrazine remediation within aquatic habitats. Literature suggests that macrophyte richness enhances the functionality of constructed wetlands (CWs), but the predominant practice is monocultures. The functional diversity within macrophyte communities is crucial for optimal performance of CWs for contaminant remediation. CWs with diverse growth forms exhibit enhanced plant growth and superior nutrient removal capabilities. The study evaluates atrazine removal efficacy of polyculture and monoculture plantation, monitoring the efficiency of various individual macrophyte, such as Canna indica and Phragmites Australis for atrazine detoxification. The findings could guide the formulation of sustainable and efficacious atrazine remediation strategies, safeguarding water quality and the integrity of aquatic ecosystems.

How to cite: Pilla, S. K., Jain, M., Ghosal, P. S., and Gupta, A. K.: Atrazine Removal in Constructed Wetlands: Efficacy of Monocultures versus Polycultures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15345, https://doi.org/10.5194/egusphere-egu24-15345, 2024.

Over the last decade, a combination of economic uncertainty, supply shocks, and extreme climate events has led to a renewed prevalence of undernourishment, posing a serious threat to the realization of the Zero Hunger Sustainable Development Goal. Future scenarios are likely to be even more challenging to its accomplishment, based on projected trends of population growth and human-induced climate change impacts. There is urgent need for the development and implementation of sustainable transformation pathways to make agri-food systems worldwide more resilient and capable to sustain these pressures. These pathways should include a wide range of actions, targeting all stages of the value chain. Reducing food loss and waste (FLW), which currently accounts for approximately one-third of the food produced, is considered among those with the largest potential, with significant environmental co-benefits on the Water-Energy-Food-Ecosystem Nexus. The presence of complex and tele-coupled trade networks however, together with the lack of robust and granular datasets, make it difficult for researchers to run detailed analyses on this issue.

In this work we estimate the FLW associated to the consumption of a wide range of staple crops globally, disaggregating between the single food commodities and the different stages of the value chain. Moreover, we investigate the associated impacts on the water, land, and energy resources. The methodology applied allows us to trace the environmental impacts from the countries of production and manufacturing, where resources have been used, to the countries of consumption (from farm to fork) and backwards (from fork to farm), offering a dual perspective on the complex system. Our preliminary results show that over 20% of the quantities cultivated are wasted through FLW, globally. Transnational flows of FLW – and of associated virtual resources – compose a vast multi-layered network involving most of the countries worldwide. Differentiated impacts are observed, depending on the countries’ role in the network: while large exporters bear substantial impacts of FLW occurring abroad on their resources, net-importing nations transfer large portions of the environmental effects of the FLW associated with their consumptions onto foreign stocks. The ability to discern between the single food commodities, without aggregating primary and derived products, increases the level of specificity from past research. This detailed data is valuable for informing public policies, providing a more fine-grained approach to prioritize efforts in reducing FLW and its associated impacts.

How to cite: Semeria, F., Falchetta, G., Vinca, A., Laio, F., Ridolfi, L., and Tuninetti, M.: Food loss & waste of staple crop products: mapping environmental impacts within the Nexus paradigm, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16795, https://doi.org/10.5194/egusphere-egu24-16795, 2024.

Disinfection is a critical drinking water treatment procedure to guarantee water safety in urban water supply systems. However, an inevitable consequence is the generation of secondary pollutants, referred to as disinfection byproducts (DBPs). Toxicological researches have linked the ingestion of DBPs to harmful human health consequences like a higher risk of bladder cancer, reproductive problems, etc. Subsequently, the water authorities face immense challenges due to their existence in the drinking water. The foremost approach to limiting their generation in the drinking water is to eliminate their precursors prior-to disinfection. Humic acid (HA), a significant constituent of the natural organic matter in surface water, has been acknowledged as the primary precursor of DBPs. Thus, the present work aims to reduce humic acid content in water by magnesium oxide (MgO) adsorbent. To ascertain the mechanism of humic acid removal, characterizations of the adsorbents were conducted both before and after. At neutral pH level, the impacts of various process parameters are examined, including contact time, adsorbent dosage, initial humic acid concentration, and temperature. Moreover, studies were performed to assess the effects of different solution pH on the elimination of humic acid. The removal of humic acid was found to be increased at low pH. At pH 3, over 85% elimination was obtained. Furthermore, the role of several anions, including nitrate, sulfate, and chloride, in the adsorption of humic acid has also been evaluated. Overall, the present study would be conducive to proving the applicability of MgO for the reduction of HA and other organic matter from water and, hence, reduce the generation of DBPs.

How to cite: Sinha, R. and Ghosal, P. S.: Adsorptive removal of humic acid from water by magnesium oxide, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18001, https://doi.org/10.5194/egusphere-egu24-18001, 2024.

Life Cycle Assessment (LCA) is a systematic approach used to evaluate the environmental impacts of products, services, or activities throughout their life cycle, from raw material acquisition and production to use and final disposal or recycling stages. The goal of LCA is to comprehensively assess environmental impacts across the entire life cycle, including energy consumption, greenhouse gas emissions, water and land use, and more. The execution of LCA primarily involves four stages: "goal and scope definition," "life cycle inventory," "life cycle impact assessment," and "life cycle interpretation." This method helps identify and improve environmental hotspots in products or activities, aiming to reduce adverse impacts on the environment.

This study references the "Packaging Lunch Box Product Category Rules" published by the Environmental Protection Administration of the Executive Yuan in Taiwan. Using a vegetarian lunch box manufacturer in Taiwan as a data source, a "Vegetarian Lunch Box Carbon Footprint Calculation Tool" was developed using SimaPro. Users can input first-tier data for each stage of the product life cycle (such as raw material input, energy, transportation distance, and output products), enabling the calculation of the carbon footprint of the vegetarian lunch box.

However, during the "life cycle interpretation" stage, this study found that the "raw material acquisition stage" contributes 80% of the carbon footprint throughout the entire life cycle of the vegetarian lunch box. This indicates significant negative environmental impacts during the "agricultural production" process. As a result, the study traces the environmental impacts of upstream agricultural production processes for grains and vegetables and proposes an improvement strategy: regenerative agriculture.

Regenerative agriculture practices include protective tillage to reduce physical soil disturbance, increasing biodiversity in fields, cover cropping to enhance soil carbon and prevent erosion, crop rotation for balanced soil nutrient use, and refraining from using chemical fertilizers and pesticides. The goal of regenerative agriculture is to sequester carbon in the soil and above-ground biomass, reducing greenhouse gas emissions, increasing crop yields, enhancing resilience to unstable climates, and improving the health and vitality of rural communities.

This study will also employ the life cycle assessment method to collect inputs and outputs for both conventional farming practices and regenerative agriculture, comparing their environmental impacts.

How to cite: Chen, C.-K. and Tung, C.-P.: Application of Life Cycle Assessment in Vegetarian Lunch Box: Environmental Impact Hotspot Analysis of Whole Grain and Vegetable Production, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18099, https://doi.org/10.5194/egusphere-egu24-18099, 2024.

• Motivation, problem statement and aim

Cowpea is an important source of protein in the semiarid parts of sub-Saharan Africa. Even under water or temperature stress, cowpea can produce grain and fix nitrogen. The robustness of cowpea makes them a good choice especially for smallholder farmers with limited resource. Inoculated cowpea is not only more resilient against many plant diseases, but also can fix nitrogen more effectively.

Located in sub-Saharan region, water supply is a constant struggle of Namibia. In addition, due to dry climate and soil characters, only 1% of the country is arable. In contrast to harsh natural condition, over 70% of population depends their livelihoods on agriculture. For insufficient production, food supply in Namibia is highly dependent on imports. This combination of natural and societal condition puts Namibian population into nutrition hazard.

Thereby, the study aims to investigate the potential of cowpea inoculation in Namibia by answering the following questions:

1) How much can inoculation increase cowpea production in Namibia?

2) How much land and water resource can be saved by introducing inoculation in cowpea cultivation?

• Methodology

Environment Policy and Integrated Climate (EPIC) model is adopted for crop simulation. It is calibrated specifically to the Namibian agricultural environment. Different climate scenarios and agricultural management systems are simulated in EPIC. The simulation result is used in optimisation modelling using General Algebraic Modelling System (GAMS). The model is simulated under objective of maximum food production given the current population.

• Result

Primarily, potential cowpea production is depicted in both inoculated and non-inoculated scenarios. The simulation considers the total arable land of the country and subsistence farming as the only farming management. Cowpea production increases by 26% with inoculation.

The land and water use of inoculated cowpea cultivation is shown in relative to non-inoculated cowpea cultivation. In the perspective of current resource availability, the relative resource use is elaborated. Inoculation saves up to 23% of land and 79% of water use.

• Conclusion

By introducing inoculation in cowpea cultivation, Namibia is expected to have meaningful increase in production and decrease in both land and water use. Since cowpea is already well integrated in smallholder farmers’ practice, the adoption of inoculation can penetrate the positive effects into remote and vulnerable areas.

How to cite: Jeong, J., Jantke, K., and Schneider, Uwe. A.: Exploring the potential of cowpea inoculation in Namibia for improved resource use and human nutrition, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20605, https://doi.org/10.5194/egusphere-egu24-20605, 2024.

The rural areas of the SUDOE present many common challenges related to the integrated water cycle: the scarcity of water resources (aggravated by climate change), the impact of agricultural and livestock activities on water quality (and the consequent difficulty of reconciling compliance with the European directive, the continuity of economic activity and the availability of water) and the lack of efficiency and profitability in management (with obsolete facilities and few human resources).
It is essential to strengthen collaboration networks between the many stakeholders involved in water resources management in order to implement efficient, sustainable and cost-effective techniques for water purification, reuse and treatment. To this end, it is necessary to create a new governance system based on territorial cooperation. Water is a common good and, as such, it does not understand borders.
The project will develop a strategy to improve water efficiency and quality in rural SUDOE areas in a context of climate change, 5 action plans for 4 organizations to improve water supply and treatment services, 3 pilot tests of cost-effective and sustainable solutions for water purification, purification and reuse, and a digital tool for 2 organizations to improve water management. In addition, it will improve the capacities of public authorities in 3 countries and the knowledge of water purification, treatment and reuse techniques like water treatment, reuse and purification techniques of 3 scientific institutions.
GestEAUr will adopt an innovative approach, addressing the integrated water cycle holistically (taking into account all its stages) and will go beyond existing practice, which tends to apply the same solutions whatever the characteristics of the territory where they are implemented.
Consequently, it will analyze and test cost-effective, cutting-edge and nature-based techniques (and combinations of techniques) (SBN) specific to the needs of rural areas in the SUDOE. It will also provide digital tools to optimize and facilitate their management and planning.

How to cite: Molina, J. L., Monsalvo, V., Encinas, A., and Lacasa, E.: Sustainable and digitalized water management in rural environments in the SUDOE area (GestEAUr project), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21484, https://doi.org/10.5194/egusphere-egu24-21484, 2024.

How to cite: Kimani, P., Foster, T., Parkes, B., Lam, S. K., and Pang, A.: Multi-sensor analysis of variability in rice transplanting dates in smallholder rice production systems in South Asia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21831, https://doi.org/10.5194/egusphere-egu24-21831, 2024.

The rapid expansion of wastewater treatment plants, aimed at mitigating global water stress, has significantly increased the energy demand. In India, the anticipated rise in sewage generation to treatment ratio from 46% to 80% by 2050 [1]. It is expected to further intensify the energy demand of treatment facilities to meet national standards. This required energy, predominantly in the form of electricity, primarily fulfill from coal-based thermal plants, consequently contributing to air pollution and emissions. Moreover, enhancing the oxygen supply in the biological process to improve treatment efficiency is projected to escalate direct greenhouse gas (GHG) emissions. India's central electricity authority reports that the Indian grid produces around 0.91 kg CO2eq/kWh. A typical wastewater treatment plant (WWTP) demands an average of 185 kWh per million litres per day (MLD), resulting in approximately 168.35 kilograms of CO2 equivalent emissions per MLD [2]. Exploring alternative mitigation measures becomes imperative to address the energy demand from the grid. One approach involves employing mitigation technologies like gasification, anaerobic digestion, or pyrolysis to generate electricity from the sludge process. The study aims to estimate direct and indirect emissions from WWTPs by conducting a comprehensive life cycle assessment of various mitigation technologies. Notably, gasification, anaerobic digestion, and pyrolysis demonstrate potential emission reductions of around 81.8%, 57.2%, and 36.4%, respectively.

How to cite: Vidyarthi, P. K., Arora, P., Blond, N., and Ponche, J.-L.: Mitigation of GHG emission from the wastewater treatment plant: Life cycle assessment approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1146, https://doi.org/10.5194/egusphere-egu24-1146, 2024.

The Ulan Buh Desert, as one of China's eight significant deserts, is situated in the country's northwestern region and encompasses a diverse array of landscapes, including various desert types, vegetation, water bodies, and other landforms. This diversity is crucial for the ecological integrity and safety of the Yellow River Basin. The desert is notably constrained by water availability, and there has been a notable expansion in the degree of human activities, particularly regarding agricultural development, in the area.

Over the past 32 years, studies tracking the temporal and spatial variations of the Normalized Difference Vegetation Index (NDVI) in the Ulan Buh Desert have revealed a consistent increase in vegetative cover. Through the analysis of drivers such as climate change and human activity, it has been determined that temperature exhibits a positive correlation with NDVI, a relationship that has strengthened progressively over the years. Conversely, precipitation's influence on NDVI has been relatively insignificant. On the human activity front, contributions to NDVI changes have grown considerably, with such activities accounting for nearly a 50% increase in the vegetative index, suggesting that human interventions are increasingly aligning with ecological rehabilitation and positive environmental outcomes.

By scrutinizing the ecological consequences of both natural processes and human endeavors on the Ulan Buh Desert, insights gleaned can offer actionable recommendations for ecological restoration efforts, ensuring the sustainable management and recovery of this vital region.

How to cite: Yan, Y. and Cheng, Y.: Study of Changes in the Ulan Buh Desert under the Dual Impacts of Natural and Anthropogenic, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1249, https://doi.org/10.5194/egusphere-egu24-1249, 2024.

China, with nearly 20% of the world's population, achieves self-sufficiency in major grain production using only about 10% of the global arable land. To further ensure food security in China, it is crucial to gain a deep understanding of the driving factors behind grain production. Climate change, water scarcity, and air pollution pose serious threats to food production. Air quality in China is among the poorest in the world, thus quantifying its impact on grain production not only holds significance for maintaining its food security but also provides valuable insights into future air quality management policies. Here, we conducted a comprehensive analysis of the impact of aerosols and ozone on crop growth by integrating long-term, high spatial-temporal resolution remote sensing SIF data, crop planting information, and nationwide air pollution concentration data using nonlinear functional relationships and a two-way fixed-effects statistical model. The results show a consistent negative impact of ozone pollution on crop growth, while the effect of aerosols is varied by crop type and geographic location. By establishing a quantitative response relationship between crop growth and pollutant concentrations, we found that when China reaches the standard of 35 µg m^-3 PM_2.5, the average yields of corn, rice, and wheat nationwide will change by 0.45 ± 0.8%, 0.70 ± 0.22%, and −5.28 ± 2.97%, respectively. At the same time, reaching a warm-season ozone concentration of 60 µg m^-3 in China will result in average national yield increases of 7.40 ± 1.32%, 3.40 ± 0.56%, and 8.71 ± 1.85% for corn, rice, and wheat, respectively. If China simultaneously meets both air pollution standards, the average daily per capita calorie intake of the three major crops will increase by 4.51%. Finally, our study suggests that, compared to reducing PM_2.5, reducing ozone can more effectively increase domestic grain supply and further maintain China’s food security.

How to cite: Liu, X., Chu, B., Tang, R., Liu, Y., Li, X., Xiao, J., Desai, A., and Wang, H.: Air quality improvements can strengthen China's food security, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1717, https://doi.org/10.5194/egusphere-egu24-1717, 2024.

Diversifying cropping systems with grain legumes has been identified as a key measure to achieve the objectives set by European policies in terms of sustainability and protein self-sufficiency. Because grain legumes are sensitive to numerous biotic and abiotic stresses, expanding their production area in the context of climate change will require the implementation of adaptation strategies.

The objectives of this study are to shed light on what knowledge is needed by stakeholders to adapt grain legume cultivation to climate change and to assess matches and mismatches between these needs and crop-climate modelling. To this aim, we performed (i) a systematic literature review (n=83) to summarise recent simulation studies that assessed the impact of climate change and adaptation on grain legume performances in Europe, and (ii) interviews with 30 stakeholders involved in different stages of the value chain in France (cooperatives, seed breeders, extension services) to identify their needs.

Stakeholders’ information needs could be grouped into three categories: (i) information on profitability (including crop yield, pre-crop effect, and economic margin) and risks associated with growing grain legumes (including yield stability and risk of crop failure) and comparison of these variables with major crops like cereals, (ii) agroclimatic indicators such as rainfall distribution, heat waves, and frost days, that can be used to adjust crop management and identify climatic constraints to the introduction of new grain legume species (e.g., chickpea and soybean), and (iii) climate change impacts on diseases, pests, and their natural enemies. The appropriate time and spatial scales at which this information is relevant depend on the stakeholder. Stakeholders supporting farmers (e.g., extension services) expressed a need for short-term (up to 10 years) and local information, whereas cooperatives and stakeholders engaged in R&D were also interested in medium-term (up to 30 years) information at multiple spatial scales (from the cooperative’s supply area to the national and European scale).

When comparing these needs with our literature review, several mismatches were identified. Although stakeholders expressed a need for short to medium-term information, the reviewed studies focused mainly on the second half of the 21^st century. The predominance of global-scale studies (63% of studies) contrasted with the need for local and regional data. We also highlight a lack of simulation studies assessing the impact of climate change on yield stability and economic indicators, especially relative to major crops like cereals. The impact of climate change on diseases, pests, and their natural enemies remains a blind spot, even though biotic pressure was identified as a growing concern for the stakeholders. Finally, although the majority of adaptation strategies identified by stakeholders (e.g., irrigation, changes in sowing date and density) have been studied in the literature, options such as substituting spring-sown crops with winter-sown crops and switching grain legume species have hardly been assessed (only one study).

Our results outline priority avenues for further research, considering the needs of stakeholders to support the development of grain legumes in Europe in the context of climate change.

How to cite: Marteau-Bazouni, M., Jeuffroy, M.-H., and Guilpart, N.: Assessing matches and mismatches between modelling and stakeholders’ needs to support the adaptation of grain legumes to climate change in Europe, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1992, https://doi.org/10.5194/egusphere-egu24-1992, 2024.

Pathogens are a factor that determines emergency responses for both the public and the safety of first responders due to their life-threatening properties. At the same time, pathogen contamination is difficult to detect, and specialized skills, tools, and procedures are needed to deal with it. Waterborne pathogen contamination accidents can occur anywhere and for a variety of reasons. Earthquakes can cause disruptions to the urban drinking water and wastewater networks, and can also be contaminated by accidents, malicious attacks, and illegal activities.

This study developed a decision support system for pathogen contamination management in disaster situations by utilizing GIS technology. The system will not only enhance the operational capability of early responders (FRs) and strengthen overall management, but also reduce errors when setting up new technologies.

The system integrates various technical means, such as collecting and analyzing satellite and drone-based water quality data and evaluating the severity of water pollution using social media data. This enables rapid and accurate detection and re-response of environmental risks. The system is interconnected with various sources through REST and open APIs, and effectively manages data by utilizing MongoDB and geo-server.

The study is expected to make a significant contribution to protecting the environment and human safety by providing an accurate risk assessment and providing the necessary technical means to respond to pathogen pollution in disaster situations. Industrial accidents can be reduced by increasing the capacity to respond to risks that have not been specifically identified and strengthening the ability to respond to disasters. The study will also provide essential data for policy-making and regulatory development aimed at protecting the environment. 

This research was supported by Korea Institute for Advancement of Technology(KIAT) grant funded by the Korea Government(MOTIE)  (P163300014, 2021 Industrial Technology International Cooperation Project - Horizon2020 Program)

How to cite: Yoon, H., Son, S., Choi, I., Jo, J., and Kwon, J.: Designing a GIS-based Decision Support System to protect environmental and human health by integrating spatial data, environmental information, and health data for informed decision-making., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3774, https://doi.org/10.5194/egusphere-egu24-3774, 2024.

Climate change is set to reshape the environmental parameters governing crop growth, necessitating the implementation of revised management practices at the field scale. This study focuses on the adaptation and evaluation of the APSIM model for simulating the phenological growth, development, and yield prediction of potato (Solanum tuberosum L.) in response to climate variability in Morocco. Recognizing the critical role of potatoes in global food systems, and the increasing pressures of climate change, the research aims to accurately forecast the growth and yield responses of potato crops to these environmental shifts. The calibration phase of the APSIM model was rigorously conducted using local datasets, including climate patterns, soil properties, plant phenological data, and cropping practices. The model's accuracy was demonstrated through its high determination coefficients in simulating key growth stages and biomass accumulation of the potato crop. The findings showcase the model's capability in predicting potato yield and phenological responses to climate variability, providing strategic insights for enhancing agricultural practice efficiency. Overall, this study underlines the APSIM model's efficacy in developing strategies for climate-resilient potato farming, offering a robust tool for adapting agricultural practices under changing environmental conditions.

How to cite: Lozzi, A., Ouedraogo, A., Darrhal, N., Dhassi, K., and Drissi, S.: Assessing adaptation strategies for potato cultivation in Morocco: modeling approaches at the field scale, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6710, https://doi.org/10.5194/egusphere-egu24-6710, 2024.

The agricultural and forestry satellite, scheduled for launch in 2025, is a satellite being jointly developed by the Ministry of Science and ICT, the Rural Development Administration, and the Korea Forest Service of South Korea. Prior to its launch, technological developments have been made to ensure the positional accuracy of the agricultural and forestry satellite. For the geometric calibration of the satellite, a total of 4,650 precise image reference points have been established across the Korean Peninsula. These established precise image reference points have been verified to have a positional error of less than 1 meter based on field survey results. Utilizing this, the Rational Function Model (RFM) was corrected, determining the optimal parameters with six coefficients as suitable RFM correction coefficients for the precise geometric establishment of simulated images of the agricultural and forestry satellite. Subsequently, using the Digital Elevation Model for orthorectification, a final positional error of within 1 pixel (less than 5 meters) was confirmed.

How to cite: Lim, J., Kim, C., Son, J.-H., Kim, T., RLee, S., Lee, J., Kim, K., and Lee, S.: Current Status of Pre-Calibration Techniques for Enhancing the Positional Accuracy of the Agricultural and Forestry Satellite, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7063, https://doi.org/10.5194/egusphere-egu24-7063, 2024.

Abstract

Digital Twins are becoming an increasingly researched area in agriculture due to the pressure on food security caused by growing population numbers and climate change. They provide a necessary push towards more efficient and sustainable agricultural methods to secure and increase crop yields.
Digital Twins often use Machine Learning, and more recently, deep learning methods in their architecture to process data and predict future outcomes based on input data. However, concerns about the trustworthiness of the output from deep learning models persist due to the lack of clarity regarding the reasoning behind their outputs.

In our work, we have developed crop rotation policies using explainable tabular reinforcement learning techniques. We have compared these policies to those generated by a deep Q-learning approach, using both five-step and seven-step rotations. The aim of the rotations is to maximise crop yields while maintaining a healthy nitrogen level in the soil and adhering to established planting rules. Crop yields may vary due to external factors such as weather patterns, so perturbations were added to the reward signal to account for these influences. The deployed explainable tabular reinforcement learning methods perform similarly to the deep Q-learning approach in terms of collected reward when the rewards are not perturbed. However, in the perturbed reward setting, robust tabular reinforcement learning methods outperform the deep learning approach while maintaining interpretable policies. By consulting with farmers and crop rotation experts, we demonstrate that the derived policies are reasonable and that the use of interpretable reinforcement learning has increased confidence in the resulting policies, thereby increasing the likelihood that farmers will adopt the suggested policies.

Keywords: Digital Twin, Reinforcement Learning, Explainable AI, Agriculture, Crop Rotation Planning, Climate Change, Food Security

How to cite: Goldenits, G., Mallinger, K., Neubauer, T., and Weippl, E.: Tabular Reinforcement learning for Robust, Explainable CropRotation Policies Matching Deep Reinforcement LearningPerformance, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9018, https://doi.org/10.5194/egusphere-egu24-9018, 2024.

Enhanced mineral weathering is a nature-based solution to reduce atmospheric and soil CO₂ concentrations in agricultural settings. Spreading finely grained basalt on the soil leads to subsequent chemical reactions that alters soil properties by changing soil pH, nutrient availability and particle-size distribution. Changes in these soil properties activate soil feedback mechanisms such as shifts in soil biogeochemical reactions or plant growth dynamics. Several studies have examined changes in pH and CEC after basalt application; however, basalt application may have an additional influence on the soil’s structural quality and the quantity of soil organic carbon (OC). In this study, we used a long-term field trial of basalt application at the University of Illinois Energy Farm (Illinois, USA) to elucidate changes in soil structure and OC storage. The field study was launched in 2016 using a randomized block design consisting of control (n=4, no basalt application), basalt (n=4), and lime (n=3) treatments. The sampling campaign was conducted in 2022 and in each field, we sampled with stainless steel cylinders (250 cm³) at depths of 1—6 cm and 15—20 cm. All samples were analyzed for nutrient content, OC concentration, pH, CEC and select samples were analyzed for soil water characteristic curves and aggregate-size distribution.

Basalt and lime application had a significant effect on soil pH, Ca concentration and the dominance of Ca²⁺ as an exchangeable cation, all which reflect evidence of increased soil structural quality. Indeed, soil structure, as quantified from the soil water characteristic curves using the concept of relative entropy (the Kullback-Leibler divergence), showed clear signs of enhancement after lime application. However, this was less evident for the basalt treatment. Despite improvements in soil structure, there were no effects on OC storage in either of the treatments. Aggregate characterization for OC concentration showed that the depth stratification had a greater role in carbon protection than the soil treatment itself, where the highest OC enrichment (E_OC>1) was observed at the lower sampling depth of 15—20 cm. The organo-mineral association in the finest fraction was not affected by the treatment because neither the aggregate size class distribution nor OC accumulation in the finest fraction differed among the control, lime, and basalt treatments. Enhanced mineral weathering improves soil nutrient content, pH, and, potentially, soil structure; however, these changes do not directly result in higher OC storage, which underlines the complex nature of OC dynamics.

How to cite: Pihlap, E., Olagaray, N., Klöffel, T., Masters, M. D., Kantola, I. B., Beerling, D. J., and Planavsky, N. J.: Effects of enhanced mineral weathering on soil structure and organic carbon storage, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10036, https://doi.org/10.5194/egusphere-egu24-10036, 2024.

The changes in rice climatic yield potential (CYP) across the Korean Peninsula are evaluated based on the new climate change scenario produced by the National Institute of Agricultural Sciences with 18 ensemble members at 1 km resolution under a Shared Socioeconomic Pathway (SSP) and Representative Concentration Pathways (RCP) emission scenarios. To overcome the data availability, we utilize solar radiation for CYP instead of sunshine duration which is relatively uncommon in the climate prediction field. The result show that maximum CYP(CYPmax) decreased, and the optimal heading date is progressively delayed under warmer temperature conditions compared to the current climate. This trend is particularly pronounced in the SSP5-85 scenario, indicating faster warming, except for the northeastern mountainous regions of North Korea. This shows the benefits of lower emission scenarios and pursuing more efforts to limit greenhouse gas emissions. On the other hand, the CYPmax shows a wide range of feasible futures, which shows inherent uncertainties in future climate projections and the risks when analyzing a single model or a small number of model results, highlighting the importance of the ensemble approach. 
This work was supported by a grant (no. RS-2021-RD009055) from the Rural Development Administration, Republic of Korea

How to cite: Jo, S., Kim, Y.-S., Hur, J., Shim, K., Hong, S. G., Kang, M., and Kim, E.: Assessment of Rice Yield Potential changes over Korean Peninsula under climate change with 1-km high resolution SSP-RCP scenarios , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13861, https://doi.org/10.5194/egusphere-egu24-13861, 2024.

In ecosystem services assessment in South Korea, many studies have applied various modelling methods. However, these modelling approaches mainly focused on the statistical growth model based on the national forest inventory, so calculating carbon was the main target of research. Statistical modelling enables annual assessment of the carbon budget in forests, but it was limited to understanding daily ecosystem changes and other material cycles. Therefore, this study tried to set up the linkage of material cycles and ecosystem services using various current modelling schemes in South Korea. Therefore, the process-based model and current forest models were applied to assess carbon and ecosystem productivity. In addition, their possible linkage to ecosystem services was analyzed. From the process-based model, the net primary productivity value was calculated at around 5.17 Mg C ha^-1 average, and it indicated around 1.61 Mg C ha^-1 in net carbon sequestration during the 2021-2100. Considering the current projection of annual carbon sequestration, this value is similar to the current model projection. In addition, the process-based model calculated evapotranspiration, respirations, and other values which converted ecosystem services, especially climate regulation, supporting ecosystem services, and provisioning ecological materials. Linkage of these models can support to assessment of many other non-assessed ecosystem services, and an ensemble of modelling and expanded modelling in ecosystem services will be required to assess Korean ecosystem services.

How to cite: Song, C., Lim, C.-H., Ko, Y., Son, J., Choi, H.-A., and Lee, W.-K.: Linking material cycles and ecosystem services assessment in forest modelling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15122, https://doi.org/10.5194/egusphere-egu24-15122, 2024.

Invasive pest species are the most serious threat to the resilience of agroecosystems. They cause direct damage by reducing crop yield and increasing management costs, and indirect damage through agroecosystem disturbances. To mitigate the risks posed by invasive pests, identifying their potential distribution is a crucial prerequisite. This study predicted the climatic suitability of the rice stem borer (RSB), Chilo suppressalis, within Europe using a species distribution model, CLIMEX. RSB first invaded Spain in the 1930s and has since caused significant damage, with reports of its presence in France, Hungary, and near the Caspian Sea in Russia. The overall suitability for RSB in Europe, while lower than its native region in East Asia, is predicted to be habitable across the European mainland. Notably, the climates of Mediterranean countries (e.g., Greece, Italy, France, Spain, Croatia, etc.) are expected to be sufficiently suitable for RSB habitation. Currently, RSB is also reported in Hungary, but the exact route of invasion is unclear; thus, it is necessary to investigate whether these are extensions of the existing populations in Spain and France or the result of accidental introduction through trade. Moreover, in southern Europe, where rice production is high, there is a risk of significant damage similar to that in Spain. Therefore, quarantine and prevention measures against RSB invasion are required.

How to cite: Hong, J. and Cho, K.: Potential Invasion risk of the rice stem borer, Chilo suppressalis, in Europe using CLIMEX., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15677, https://doi.org/10.5194/egusphere-egu24-15677, 2024.

The risk of wildfires is increasing due to rising temperatures and worsening dry conditions resulting from climate change (Westerling et al., 2008; Vilà-Vilardell et al., 2020). Human activities, driven by urbanization and population growth, contribute to the occurrence of wildfires. As wildfires are a consequence of the complex interplay of various factors, an integrated understanding of the social and ecological systems influencing wildfires is crucial for protecting human communities and preserving the natural environment. Particularly, the Wildland-Urban Interface (WUI), an area where urban and natural landscapes and vegetation coexist or are adjacent, represents a space where the interaction between human activities and natural systems is pronounced (Stewart et al., 2007). A specific and clear analysis and management of the WUI’s social-ecological system is necessary due to the severe damage caused by urban wildfires.

There is a growing awareness of the necessity to establish effective prevention and management strategies to protect urban systems. However, there is a lack of research on social-ecological systems over time, such as before and after wildfires in the WUI. Therefore, the objective of this study is to conduct a comprehensive analysis of the socio-ecological system of urban WUI areas, with a focus on identifying and evaluating the factors influencing the resilience of these systems. By examining the interactions within the WUI’s socio-ecological framework, the research aims to propose strategies for enhancing the capacity of urban areas to adapt to and recover from environmental disturbances, thereby contributing to the development of robust and resilient urban social-ecological systems.

To define and categorize socio-ecological systems, a spatial analysis of wildfire-prone areas was employed and to identify and evaluate the factors affecting the resilience of the system in response to wildfires, system analysis tools and models were utilized.

Building upon this study, future research will employ the Urban Resilience Index classification to derive strategies for each type of green infrastructure planning based on the 4Rs of resilience (robustness, rapidity, redundancy, and resourcefulness) to improve urban socio-ecological resilience for wildfire response in urban Wildland-Urban Interface (WUI). The results can be utilized to develop a green infrastructure planning decision support system.

References

Westerling, A. L., & Bryant, B. P. (2008). Climate change and wildfire in California. Climatic Change, 87(Suppl 1), 231-249.

Stewart, S. I., Radeloff, V. C., Hammer, R. B., & Hawbaker, T. J. (2007). Defining the Wildland-Urban Interface. Journal of Forestry, 105(4), 201-207.

Sullivan, A., Baker, E., & Kurvits, T. (2022). Spreading like wildfire: The rising threat of extraordinary landscape fires.

※ This work was supported by the Core Research Institute Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2021R1A6A1A10045235).

How to cite: Kang, S. and Lee, J.: Analysis of Influencing Factors to Enhance Resilience of Urban Social-Ecological Systems in Urban Wildfire Response, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16379, https://doi.org/10.5194/egusphere-egu24-16379, 2024.

To achieve the national carbon neutrality goal by 2050, it is crucial to be spatially strategic. Understanding the spatial distribution of carbon balance in different levels of spatial scales from global/continental scales to urban, and province/state is essential. This paper aims to estimate the spatial distribution of carbon balance in South Korea using an integrated carbon balance estimation model and to identify the disparity of carbon-emission characteristics determined by three different spatial divisions ¾ metropolitan and basic local governments, and town-level (eup/myeon/dong&li). Two-step ridge regression model using residuals was established based on land cover maps, population maps, and energy production data to analyse the distribution of carbon emissions. The distribution of carbon sequestration was calculated using the Korean forest growth model (KO-G-Dynamic model). The results from each model were calibrated and validated by the National Greenhouse Gas Inventory of basic local governments. The carbon balance was quantified by integrating the results of carbon emission and carbon sequestration. Surprisingly, the results showed that several cities, especially along the biggest mountain range in South Korea, have already achieved regional carbon neutrality. This is particularly true when the spatial scale is below a metropolitan government level. Additionally, the study found that the narrower the spatial scale of distribution becomes, the greater the number of urban/provinces with a carbon balance under zero. Obviously, carbon-neutral regions are characterized by low energy and industrial facilities and high forest density and, in most of the top emitting regions, vice versa. This study provides insights into the methodology for researching the spatial distribution of carbon balance. It also highlights the need for constructing carbon reduction pathways and strategies that reflect the regionality of carbon balance in multi-level districts. With further development of the study, the result could be used as scientific evidence for the effective fulfillment of regional carbon neutrality.

How to cite: Jeong, Y., Lee, S., Hong, M., Ko, Y., Jo, H.-W., and Lee, W.-K.: Are There Carbon-Neutral Cities in South Korea: Using Residual Modeling on Different Spatial Scales, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16948, https://doi.org/10.5194/egusphere-egu24-16948, 2024.

Coffee is one of the most economically important agri-food systems globally, and is the main source of income for many rural households in several developing countries. Ongoing climate change could cause problems for sustainable coffee production, with greater instability from year to year and lower average yields. To overcome these problems, possible adaptation measures and agronomic practices should be evaluated, such as intercropping with other tree species that can provide more shade for coffee plants and promote resilience and environmental sustainability. To study the effectiveness of such options, the use of process-based models can be very useful.

The DynACof model was developed specifically to simulate coffee agrosystems, including phenological development, physiological processes related to flower and fruit production, carbon allocation, the effect of water availability, light and temperature, and management. We validated the yields modeled by DynACof with productivity data available from some sites and areas included in previous evaluation studies in Mexico, Rwanda, Brazil, Ethiopia, and Costa Rica. We then developed and established a modeling framework in which the model can be applied spatially on a continental or pan-tropical scale, using extended climate projection ensemble and soil geodata.

Our modelling tool was then used to simulate potential yields in Latin America and Africa for both 1985-2014 and 2036-2065, using an ensemble of statistically downscaled and bias adjusted climate projections for two different shared socioeconomic pathways. Comparing the two periods, the model predicts a decrease in yields between 23 and 35 percent in Latin America and between 16 and 21 percent in Africa. The spatial representation of these changes indicates a likely future shift of suitable production areas to higher elevations, possibly impacting fragile mountain ecosystems. We simulated a specific management option, namely increased agroforestry shading, to evaluate its effectiveness in improving resilience to climate risks. The results suggest that increased tree shading could partially reverse the trend of declining yields due to climate change in some lowland areas. However, these preliminary results must be confirmed by further analyses. Impact analysis and adaptation modeling of coffee agrosystems, together with socioeconomic indicators, have the potential to delineate realistic integrated risk assessments and support effective adaptation recommendations.

How to cite: Della Peruta, R., Mereu, V., Spano, D., Marras, S., and Trabucco, A.: Impact of climate change on coffee agrosystems and potential of adaptation measures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17914, https://doi.org/10.5194/egusphere-egu24-17914, 2024.

The impact of anthropogenic carbon dioxide (CO₂) emissions and terrestrial ecosystems CO₂ sequestration on global climate change has been widely recognized, and regional carbon emission and sequestration patterns are receiving increasing attention. Accounting for regional anthropogenic carbon emissions and terrestrial ecosystems CO₂ sequestration is beneficial for regional carbon peak and neutrality planning. This study utilizes yearbooks, government reports, soil survey data, and remote sensing data to calculate the annual CO₂ emissions and absorption in the period 2010-2020 for Shenzhen, a typical highly urbanized area in China. We analyze the trend of net CO₂ emissions and employ the Multilevel-LMDI method to examine the various driving factors influencing anthropogenic CO₂ emissions in Shenzhen. Subsequently, emission reduction measures are proposed separately from the emission and absorption perspectives. From 2010 to 2020, Shenzhen emitted a total of 10.82 billion tons of CO₂, with terrestrial ecosystems absorbing 15.82 million tons. The net emission was 10.67 billion tons, showing an annual increase until reaching its peak in 2018 (1.12 billion tons). The primary drivers of Shenzhen's anthropogenic CO₂ emissions growth are population (5,150.42 million tons) followed by economic factors (4,279.66 million tons). Per capita food consumption (23.77 million tons) and dietary structure (6.11 million tons) also play crucial roles. The main drivers for CO₂ reduction are energy emission intensity and ecosystem carbon sinks. The study indicates that Shenzhen has entered the carbon peak phase. Controlling the growth of carbon emissions through reducing energy intensity and optimizing the energy structure has been effective. terrestrial ecosystems have played a significant role in carbon removal. However, considering the substantial anthropogenic carbon emissions, further efforts are needed in future planning to achieve ‘dual carbon goals’ by reduce population regulation, carbon emissions and enhance terrestrial CO₂ absorption.

How to cite: Yang, S.: Analysis of Carbon Balance Patterns and Driving Factors in China’s Mega Cities – A Case Study of Shenzhen, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18192, https://doi.org/10.5194/egusphere-egu24-18192, 2024.

In recent years, global climate change has emerged as a critical issue, exerting widespread impacts across various sectors. In response, the Intergovernmental Panel on Climate Change (IPCC) has emphasized the urgency of preparing for a 2℃ temperature rise by focusing on greenhouse gas reduction strategies and the vital role of forests as carbon sinks. Aligning with international efforts, South Korea has formulated the "2050 Carbon Neutrality Strategy" and presented corresponding strategies in the forestry sector. This research utilizes the Korean Dynamic Forest Growth Model to explore forest management pathways aimed at achieving carbon neutrality through the aspects of sequestration, storage, and substitution (3S). The study incorporates climate change scenarios and forest policies to select appropriate management pathways. The assessment of various scenarios revealed that the combination of the SSP1 climate change scenario, clear-cutting, thinning of approximately 200,000 hectares, reforestation with suitable species, and ensuring a maximum forest road accessibility of 1 km produced significant and meaningful results across all three aspects of forest management (sequestration, storage, and substitution). As a result, sequestration of 28.49 million tCO₂ yr^-1, a storage of 2.1 billion tCO₂ yr^-1, and the substitution 7.92 million m³ of harvested wood products (HWP) in the 2050. Furthermore, the 3S forest management approach is expected to contribute to mitigating tree-age imbalances and provide resilience against the impacts of climate change. In conclusion, this study is meaningful in that it suggested a spatio-temporal forest management path by reflecting the environmental characteristics of Korea for achieving carbon neutrality. This is considered to be able to contribute to local government carbon neutrality achievement plans and national policies.

How to cite: Hong, M., Son, J., Kim, M., Ko, Y., and Lee, W.-K.: Analysis of South Korea's 3S Forest Management Pathways for Carbon Neutrality Achievement, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18453, https://doi.org/10.5194/egusphere-egu24-18453, 2024.

Mangroves, a form of blue carbon, encompass approximately 1,054,900 hectares globally, with Vietnam possessing 75,900 hectares, representing around 7% of the total area. Beyond providing essential resources such as food, timber, and habitat, mangroves confer diverse ecosystem services, including coastal erosion mitigation and carbon sequestration while attenuating wave energy. Nevertheless, the pervasive impacts of climate change and anthropogenic activities are precipitating a reduction in mangrove coverage, giving rise to socio-ecological challenges, including biodiversity loss, escalated carbon emissions, and heightened vulnerability to severe flooding. Efforts are underway to address this predicament; however, accurate assessment remains challenging due to the intricate nature of mangrove habitats. Survey-derived data suffers from accuracy limitations, necessitating comprehensive research utilizing satellite imagery for efficient identification within a condensed timeframe, employing a systems thinking approach to understand complex ecosystem services holistically.

This research aims to detect changes in the area of mangrove forests in Vietnam using Landsat satellite imagery from 2010 to 2020, the initial implementation period of the Vietnam Forestry Development Strategy, and to analyze the impact of these changes on ecosystem services.

To achieve this, high-resolution (30cm) satellite images are utilized to calculate specific vegetation indices such as NDVI, NDWI, and SAVI in QGIS software.

 These indices are instrumental in detecting alterations in mangrove coverage throughout Vietnam. Additionally, this study employs systems thinking to construct a causal chain map that illustrates how changes in the mangrove area impact ecosystem services within Vietnam.

Satellite imagery was harnessed for GIS analysis to evaluate the ongoing status of Vietnam's mangrove forest area over time. The alterations in the area were quantified by grid partitioning, and causal loop diagrams were utilized to comprehend how modifications in mangrove areas affect ecosystem services such as coastal protection, water purification, habitat provision, and food supply. These changes engender trade-offs.

This study is significant as it utilizes high-resolution satellite data to quantify the change in Vietnam's mangrove forest area over time. It also underscores the impact of these changes on ecosystem services from a systems-thinking perspective. Moreover, deducing the ecosystem service structure of mangrove forests from causal chain maps can serve as a cornerstone for formulating policies aimed at safeguarding mangrove forests for decision-makers in Vietnam and other countries with similar ecosystems. Additionally, exploring the potential of mangroves as blue carbon sources can contribute significantly to carbon neutrality and planning.

Acknowldegemt

This research was supported by "Development of living shoreline technology based on blue carbon science toward climate change adaptation" of Korea Institute of Marine Science & Technology Promotion (KIMST) funded by the Ministry of Oceans and Fisheries (KIMST-20220526)

How to cite: Tae, M., Kim, M., and Chon, J.: Systematic Analysis of the Impact of Mangrove Forest Changes on Ecosystem Services in Vietnam, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18916, https://doi.org/10.5194/egusphere-egu24-18916, 2024.

Renewable energies, particularly solar and wind power, are gaining prominence in the shift towards a carbon-neutral climate. however, challenges for wind power include ecological disruption, coastal landscape degradation, and visual impact due to offshore turbine installation. Technological limitations currently dictate offshore wind turbines' placement 10 to 30 kilometers inland, raising concerns about light environmental changes affecting nearby coastal areas. This raises concerns about the potential impact of light environmental changes such as the effects of aviation obstruction lights on wind turbines and blade movements on inland areas close to the coastline.  Therefore, developing offshore wind farm plans analyzing the impact of light environment changes and proposing mitigation measures is crucial.
In this study, we analyze the light environmental impact of wind power and propose mitigation measures to minimize its effects on the planned offshore wind farms in the South Sea's Aphae area, surrounded on three sides by sea and offering favorable conditions for marine renewable energy development, and the West Sea's Jangbogo area in South Korea.
The assessment utilized 2022 Day and Night Band (DNB) satellite imagery from the VIIRS sensor to evaluate light pollution. QGIS was subsequently employed to analyze visible frequency, turbine shadow impact range, and distance from the power generation site, resulting in a light environment value assessment map. Key points were identified on the map, and the study further examined the influence of turbine blade movements on aviation obstruction lights and shadow flickering using QGIS and WINDPRO.
As a result of measurements using VIIRS satellite images, the light pollution levels at the Aphae and Jangbogo sites were found to be approximately 0.631542 × 10-9 W/cm²sr and 0.38 × 10-9 W/cm²sr, respectively. In Aphae, the impact of light pollution was generally minimal, less than 0.002 cd/m², but it did have an impact in the northern coastal area. Jang Bogo measured less than 0.002 cd/m², indicating a low impact on island residents.
As a result of light pollution analysis, it was found that shadow flickering occurs for 30 to 60 minutes a day for more than 120 days a year in the northern coastal area of Aphae. Jangbogo showed very limited shadow flickering, less than 10 hours per year and less than 10 minutes per day in certain areas. The impact of light pollution is expected to be minimal in Jang Bogo, and mitigation measures are needed to alleviate pressure damage. Recommendations may include adjustments to the layout of offshore wind farms or changes to the coordination of offshore wind operations.
This study is significant in analyzing the impact of light environmental changes caused by offshore wind power on inland areas and proposing mitigation measures. Furthermore, the findings of this research can be applicable to environmental studies for the development of offshore wind farms in other regions in the future.

Acknowledgement

This research was supported by “Development of Advanced Science and Technology for Marine Environmental Impact Assessment” of Korea Institute of Marine Science & Technology Promotion (KIMST) funded by the Ministry of Oceans and Fisheries (20210427)

How to cite: Choi, H., Kim, M., and Chon, J.: Assessing Light Environmental Impact in Offshore Wind Farm: A Case Study of Aphae and Jangbogo Areas in South Korea, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19001, https://doi.org/10.5194/egusphere-egu24-19001, 2024.

Climate change is altering weather patterns around the world, and one notable effect is changes in the jet stream that controls weather systems. As the polar regions warm faster than lower latitudes, the temperature difference that drives the jet stream winds decreases, causing them to become more frequent and the air masses to stagnate. This could lead to prolonged periods of extreme weather, including deadly heat waves, floods and droughts. An example of this can be seen in 2018, when a heat wave broke record high temperatures in Korea due to blocking (a phenomenon in which air flow stagnates in the upper mid-latitudes, weakening westerly winds and causing strong north-south winds) by Rossby waves. Life-threatening heat persists without an increase in low-pressure systems that bring cooling rain.

This study uses a systems ecology approach to examine the interactions between energy and material cycles in interconnected ecosystems in East Asia. The region's rapid urbanization, industrial growth, and high population density have significantly altered heat and material flows and cycles. These anthropogenic changes, together with natural climate variability, have complex and far-reaching impacts on regional climate patterns and ecosystem health.

East Asia's built environment and demographics have fundamentally disrupted natural stability mechanisms. Rapid development has replaced heat-reflecting green spaces with heat-absorbing concrete structures, reducing evaporative cooling capacity. Sprawling road systems filled with vehicle heat exacerbate urban heat islands.

In addition, climate-induced changes in the natural cycles of water, carbon, and nutrients link ecosystems in complex ways. Quantifying changes in cycling by evaluating historical data and models provides a basis for predicting ecosystem stability and resilience in the face of climate change. For example, a decrease in relative humidity in an area increases the risk of wildfires as moisture is removed from dead grass, fallen trees, and leaves. In areas with low relative humidity and abundant fuel-rich vegetation, the risk of wildfires may increase, particularly in winter and spring. A systematic understanding of these dynamics is essential to guide regional climate change adaptation planning.

Finally, the study translates its findings into policy recommendations. By analyzing the positive impacts of increased plant cover on humidity and overall ecosystem water availability, this study provides actionable steps towards a more resilient East Asia.

Acknowledgements: This research was supported by the Core Research Institute Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2021R1A6A1A10045235).

How to cite: Park, H., Song, C., and Lee, W.-K.: Impacts of Climate Change on the Energetics and Ecosystem Material Cycles and Extreme Weather Events: An East Asian Case study, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19195, https://doi.org/10.5194/egusphere-egu24-19195, 2024.

This study aims at identifying the carbon dioxide reduction (CDR) potential of large-scale and multi-purpose afforestation/reforestation at the global level with special emphasis on the Mid-Latitude Region (MLR). Applying a combined remote sensing/GIS approach coupled with biophysical forest and disturbance modeling under various climate change scenarios, we identify potential afforestation locations, inter-alia on abandoned agricultural land and on areas burnt from wild land fires. With the help of IIASA’s biophysical global forestry model (G4M), we calculate the associated land-based CDR potentials through carbon sequestration in afforested biomass and through climate risk-resilient and sustainable forest management dedicated to the supply of bioenergy plants coupled with carbon capture and storage (BECCS) facilities. Finally, three promising scenarios have been identified including I) afforestation; II) reforestation; and III) BECCS. In all scenarios, priority is put on sustainable forest management and nature/biodiversity conservation. Forest modeling results have been combined with recent data sets which have been overlayed in order to provide a unique basis to estimate the land-based CDR technologies’ potential to mitigate climate change and contribute to reaching the goals of the Paris Agreement. In the case of afforestation, preliminary results indicate a total potential afforestation area greater than 1 billion ha.  The largest area potential for afforestation have been identified in the USA. Given the higher productivity (combined with large area available), Brazil is the country with the highest total CDR potential of close to 500 MtC/yr.

How to cite: Kraxner, F., Schepaschenko, D., Fuss, S., Krasovskiy, A., Shvidenko, A., Kindermann, G., Jo, H.-W., and Lee, W.-K.: Multi-purpose afforestation scenarios under climate change for carbon dioxide reduction , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19777, https://doi.org/10.5194/egusphere-egu24-19777, 2024.

Due to climate change, abnormal weather conditions such as floods, droughts, heavy snow, and heatwaves are escalating globally. Recent climate observations and model predictions indicate a trend toward more frequent and intense extreme climate events in the near future, attributed to anthropogenic greenhouse gas emissions. When floods occur, they simplify the habitats of ecosystems, leading to a reduction in diversity and water quality pollution. Basin ecosystems play a crucial role in carbon absorption, mitigation, and providing habitats for plants and animals. Therefore, it is imperative that plants, soil, and wetlands within the watershed ecosystem absorb and sequester carbon from the atmosphere to decrease greenhouse gas concentrations. Consequently, there is a necessity for research on decision support tools capable of identifying and analyzing the factors influencing carbon circulation during a flood.

The primary objective of this study is to develop a decision support tool for green infrastructure (GI) planning in watershed ecosystems to enhance resilience against climate change. The tool will help identify and analyze factors affecting the carbon cycle during flood events and enable the creation of GIs that support the carbon cycle.

The expected results from the study combine positive factors that can lead to various positive and combining factors, so future research can create scenarios through combinations of factors. The scenarios created can result in GIs that can perform ad hoc tasks by choosing more efficient configurations.

References

Michael W. Strohbach, Eric Arnold, Dagmar Haase. The carbon footprint of urban green space—A life cycle approach. Landscape and Urban Planning, Volume 105, Issue 4, 30 April 2012, Pages 445

※ This work was supported by the Core Research Institute Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2021R1A6A1A10045235).

※ This work was supported by Korea Environment Industry &Technology Institute (KEITI) through "Climate Change R&D Project for New Climate Regime.", funded by Korea Ministry of Environment (MOE) (2022003570003)

How to cite: Bi, J., Lee, S., and Lee, J.: A Green Infrastructure Approach through Carbon Cycle Analysis and Decision Support, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20157, https://doi.org/10.5194/egusphere-egu24-20157, 2024.

Abstract

The expansion of impervious surfaces resulting from urbanization induces alterations in the natural water cycle system, culminating in urban flooding. Persistent flood damage arises from issues such as the failure to designate flood-prone areas despite receiving flood reports or the exclusion from flood-prone zones due to complaints. Both the central government and local authorities are taking measures to designate and manage flood-prone areas, recognizing the necessity to address this issue not only from an ecological standpoint but also considering social aspects, including the real estate value of the region and the effort and cost of flood damage recovery. Furthermore, flood resilience should be a central consideration, aiming to identify existing problems through the virtuous cycle process of flood damage, both upstream and downstream, and working towards recovery or improvement to a state superior to pre-flood conditions.

This study's objective is to redefine the criteria for green infrastructure planning in flood-prone zones, exploring interrelated factors influencing urban water systems and identifying synergistic solutions to enhance resilience. The application of systems thinking involves four integral stages: dynamic thinking, causal thinking, closed-loop thinking, and strategic discovery. These stages collectively establish a systematic dynamic loop. To construct this loop within the complexity of a water circulation system, initial attention must be given to discharge management. Ensuring a robust water cycle necessitates the equitable distribution of runoff across processes such as evaporation, filtration, infiltration, and groundwater recharge. Secondly, green infrastructure design should leverage technologies that harness natural mechanisms, enhancing the cyclical movement of materials within the ecosystem. This involves strategic infrastructure planning that minimizes alterations to topography, preserving the natural functions of the water cycle while allowing for flexible application tailored to ecosystem requirements. These green infrastructure characteristics, effects, and plans are summarized as variables. Thirdly, the dynamic loop is constructed with consideration of the summarized variables. The final stage of the process integrates flood risk management within a community flood resilience framework. By cycling through the stages of learning, prevention, resistance, response, and recovery, the objective is to minimize damage caused by floods and effectively respond to unexpected floods due to climate change.

As a result, seven derived criteria include land use type identification, target site characteristics analysis, detailed survey, water circulation goal selection, design criteria and layout strategy, spatial suitability evaluation, and water cycle change verification. Using these criteria, the ultimate goal of this study is to identify suitable green infrastructure locations and create a monitoring map for a healthy water cycle. The study aims to contribute to flood prevention measures in flood-prone areas by analyzing the impact of green infrastructure on emissions.

Acknowledgements

This work was supported by Korea Environment Industry &Technology Institute (KEITI) through "Climate Change R&D Project for New Climate Regime.", funded by Korea Ministry of Environment (MOE) (2022003570003).

References

EPA, U. (2007). Reducing stormwater costs through low impact development (LID) strategies and practices. United States Environmental Protection Agency, Nonpoint Source Control Branch (4503T).

How to cite: Lee, W. J., Jeon, S., and Lee, J.: Green infrastructure planning criteria for flood-prone areas to restore water cycle system and improve flood resilience , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20208, https://doi.org/10.5194/egusphere-egu24-20208, 2024.

Phenology has been regarded as an essential bio-indicator of climate change widely. Quantifying the crop phenological changes caused by climate change and anthropogenic-management practices can help formulate effective climate change adaptation strategies. In this study, the effects of climate change and anthropogenic-management practices on maize phenology (spring, summer, and intercropping maize) in China were distinguished based on historical meteorological and phenological data (1981–2010) of 114 stations using the first-order difference regression method. Our results show: (1) The vegetative growing period of spring and intercropping maize was extended, whereas that of summer maize was shortened. The reproductive growing periods of spring, summer, and intercropping maize were extended. (2) Isolated impacts of climate change shortened the vegetative growing period of spring maize, summer maize, and intercropping maize by 0.19, 1.06, and 3.12 d decade−1, respectively, while the reproductive growing period was extended by 0.19, 0.74, and 3.47 d decade−1, respectively. (3) The contribution of temperature to maize phenology was greater in the northwest inland maize zone and north spring maize zone than in other regions, whereas the contribution of sunshine hours was higher in Huang-Huai Plain intercropping maize zone and the southwest mountain hills maize zone. (4) The effects of anthropogenic-management practices on maize phenological stages such as sowing, emergence, and maturity were generally greater than that of climate change, which has delayed the phenological stages of summer and intercropping maize and extended the growing period of spring maize. The focus should be paid to the emergence, jointing, and milky stages to increase the water use efficiency in the northwest inland maize zone. The findings provide a scientific basis for improving the adaptability of agricultural systems in climate change.

How to cite: Chen, J., Liu, Y., Zhang, J., Zhang, E., and Liu, J.: Assessing the adaptability of maize phenology to climate change: The role of anthropogenic-management practices, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21387, https://doi.org/10.5194/egusphere-egu24-21387, 2024.

Global change encompasses on the environmental side components such as climate change, land degradation and pollution; and in the societal domain socioeconomic changes such as demography, economic development, and equality. This nexus is primarily driven by human activities and affects outcomes relevant for peoples’ well-being and viability through a network of interactions and feedbacks. Due to its strong influence on land surface and land-atmosphere processes and as a basis for food security and income, agriculture and rural livelihoods are at the heart of global change.

Despite the close entanglement of rural populations, livelihoods, and agricultural production, their integrated assessment is so far hardly considered in large-scale and global foresight studies. Instead, most large-scale research on consequences of global change and potential solutions is still monothematic or combines few of the above elements.

Integration across disciplines is taking place only to a limited extent, typically with static combinations of model outcomes. E.g., integrated land use models typically combine yield projections for changing climate with a priori projections of economic and population change. Other examples are the combination of independent projections of crop productivity and water availability to analyze adaptation potentials within the biophysical domain or across scientific domains the estimation of migration driven by changes in crop productivity and water availability. Importantly, both mono- and interdisciplinary studies are most often confined to business-as-usual scenarios or trajectories along shared socioeconomic pathways. Consequently, they do not capture feedbacks involving the human dimension and potentials for adaptation, and therefore lack outcomes that can inform on options for local and regional decision-making covering the water-food-population nexus.

The state-of-the-art highlights a concerning lack of integrated approaches to model global change impacts and feedbacks across environmental and socioeconomic domains. Based on own research and literature that characterizes interactions in the water-food-population nexus under global change pressures and existing model types and approaches, we propose herein a platform for the quantitative integrated modelling and assessment of global change impacts and adaptation covering food and water security, land use, demography, migration, and adaptive capacity.

Applications of such a modelling platform may address a wide range of pressing questions including shocks, their cascading effects and ultimate feedbacks (e.g. food security through output and input trade during and after Ukraine war; other historic shocks such as financial crisis; etc.); slow-onset global change impacts and adaptation; or transversal achievement of SDGs; and eventually serve as a first step towards the modelling of societal catastrophic change scenarios.

How to cite: Folberth, C., Burek, P., Kahil, T., Kraxner, F., Kuhn, M., Palazzo, A., Wrzaczek, S., and Yildiz, D.: Towards a better integration of the human and biophysical dimensions in global change modelling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22025, https://doi.org/10.5194/egusphere-egu24-22025, 2024.

Carbon capture and storage technology is a necessary means to achieve the temperature control goal of 1.5 degrees Celsius under the background of peak carbon dioxide emissions and carbon neutrality. The storage of carbon dioxide in oil and gas reservoirs has the advantages of high safety, large storage capacity, and less additional cost. The reservoir-caprock configuration can provide favorable space for the storage of carbon dioxide geological bodies. To make clear the distribution range of geological bodies suitable for carbon dioxide sequestration, taking the middle-south section of the eastern sag of Liaohe as an example, based on the model of the ratio of mud to ground and caprock effectiveness division, the control factors of caprock sealing were analyzed by entropy weight method combined with TOPSIS method, and the effective thickness of reservoir was determined by clarifying the relationship between reservoir lithology, physical properties, oil content and electricity. The results show that the lower limit of the effective caprock mud-to-ground ratio in the sand-mud interbedding sequence is 70.6%, and the sealing ability of caprock is mainly affected by the thickness of the fault and the thickness of the caprock single layer; The two sets of caprocks in the Shahejie Formation and Dongying Formation are relatively stable, with good fault-caprock configuration sealing, and the fault juxtaposition thickness in the Shahejie Formation is characterized by "thick in the north and thin in the south"; The effective reservoirs of the Dongying Formation are distributed in the whole region, the effective reservoirs of Es1 are distributed in the north of Rongxingtun, and the distribution range is smaller than that of the Dongying Formation, while the effective reservoirs of Es3 are mainly distributed in Huangyure area at the northern end of the study area, and the distribution range is further reduced. According to the reservoir-caprock configuration, carbon dioxide storage types can be divided into three types: shallow storage type, deep storage type, and multi-layer storage type. The lower caprock is well sealed and the lower effective thick reservoir controls the deep enrichment of carbon dioxide; The lower caprock is poorly sealed, and the effective thick reservoir in the middle or upper part controls the multi-layer enrichment of carbon dioxide; The lower caprock is poorly sealed, the upper caprock is well sealed, and the upper effective thick reservoir controls the shallow enrichment of carbon dioxide. The relationship between the effective thickness of the reservoir and the sealing ability of the caprock determines the vertical distribution series of carbon dioxide.

How to cite: li, H. and jiang, Y.: Study on Reservoir-caprock Configuration for Carbon Dioxide Sequestration in oil and gas reservoirs , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-86, https://doi.org/10.5194/egusphere-egu24-86, 2024.

Global warming poses a major challenge that humanity will face during the 21^st century, requiring a significant reduction in anthropogenic CO₂ emissions to mitigate the escalating global temperature. Several governments worldwide, including Brazil, have committed to achieving net-zero CO₂ emissions by 2050, which will be impossible without Carbon Capture, Utilisation and Storage (CCUS) deployment. Ranked 12^th globally in CO₂ emissions (and 1^st in South America), Brazil is in the early stages of studying CCUS. At present, CCUS efforts in the country primarily revolve around enhanced oil recovery, with limited exploration of CO₂ injection in alternative geological settings. A total of 31 sedimentary basins span Brazilian territory, encompassing an area of approximately 6.4 million km², 75% of which is situated onshore. The potential for CO₂ storage in saline aquifers is gaining attention globally, proving a successful and effective approach in various sites. In this work we combine the available surface (geological maps, roads, and gas pipelines) and subsurface data (seismic lines and borehole data) to assess the logistics and feasibility of utilizing saline formations in onshore intracratonic basins as CO₂ sinks, aiming to enable Brazil to reach net-zero CO₂ emissions by 2050. Previous studies indicate that the Parnaíba, São Francisco, Amazonas, and Paraná basins present saline formations with favorable characteristics for CO₂ injection, such as adequate depths, porosity, and permeability. Building upon prior research, we introduce the onshore portion of Espírito Santo Basin to the list of potential sinks, where the target saline aquifer is the pre-salt Mucuri Formation. Results show that greenhouse gases emissions from industrial processes are notably higher in the southeast region of Brazil. Within this region, two formations exhibit considerable potential for carbon sequestration in saline aquifers: (i) the Mucuri Formation, located in the onshore Espírito Santo Basin, reaching 350 m of thickness and shallowest depths of about 950 m, and (ii) the Rio Bonito Formation, in the proximities of the São Paulo state, with over 100 m of thickness and shallowest depths of about 650 m. For large-scale projects, CO₂ transport in the region can be accomplished using the available infrastructure and the available gas pipelines, while smaller-scale research projects can utilize trucks, rail, and ships. Brazil's untapped potential for CCUS presents a unique funding opportunity from the private sector, marking a crucial step toward sustainable and impactful climate action.

How to cite: B. Amarante, F., Kuchle, J., and B. Haag, M.: Towards net-zero: assessing the carbon storage potential of onshore saline aquifers in Brazil, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-362, https://doi.org/10.5194/egusphere-egu24-362, 2024.

Despite constituting two-thirds of the sedimentary rock volume, shales are a few of the least understood rocks. The varied depositional processes and environments give rise to complexity and anisotropy in them. Understanding unconventional resources like shales becomes crucial given their abundance in the petroleum systems and reservoirs and their potential suitability for sub-surface carbon and radioactive waste storage. Therefore, paramount significance lies in understanding the petrophysical and rock physical characteristics of shales to develop feasibility models for the sustainable use of these rock types.
 
This investigation focuses on the Barren Measures and Raniganj Formation shales in the Damodar Valley of Eastern India, which are primarily rich in clays, carbon, and iron and are of fluvio-lacustrine origin. These relatively shallow formations can be good sites for storage and sequestration as they are overlain by shaley and clayey formations acting as traps. The anisotropy in shales is even more challenging as its imponderables range from a micro to a macro scale. This changes even further with factors like organic-hosted porosity and maturity. The inherent anisotropy in shales necessitates a multiscale examination. These multiscale discontinuities, coupled with parameters like organic matter and maturity, impact the elastic properties of the rocks, as evidenced by the ultrasonic evaluations.
 
In this study, acoustic characterization of samples was conducted using a benchtop ultrasonic wave propagation setup. The samples were clustered based on their colour and observed megascopic properties. Some sandstones were also included in the study to contrast sandstones with respect to shales. The wave velocities were determined for samples subjected to progressive heating up to 200°C (gas window), and the consecutive changes in the elastic parameters and resultant wave velocities of the rock were studied. Inputs from other methods utilizing different physics, such as FE-SEM, XRD were integrated to refine our interpretation. Notable changes were seen in wave velocities, especially in clusters with elevated organic content, while the density and Vp cross plots gave a good correlation with an R² value of around 0.7.
This study advances our understanding of the impact of temperature on the elastic properties of shales, an aspect less explored than factors like stress and pressure. Thoroughly characterizing these parameters through acoustic methods provides critical insights into shale's storage capacity, carbon sequestration potential, and additional hydrocarbon recovery, specifically with respect to the Damodar Valley shales, aiding India to offset the projected peak of 4 GT CO₂ emissions to achieve the carbon neutral goal promised at COP 26 and fulfilling UN Sustainable Development Goals.

How to cite: Jamwal, V. D. and Sharma, R.: Ultrasonic Evaluation of Shales vis-à-vis Temperature: A Case Study from Permian Damodar Valley Basin, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-800, https://doi.org/10.5194/egusphere-egu24-800, 2024.

Abstract: Fractured carbonate reservoirs are of great importance in the oil industry due to their significant role in global oil reserves and complex nature, where the majority of these reservoirs are naturally fractured, making them complex and challenging for oil recovery. The detection and characterization of fractures are essential for understanding the reservoir's petrophysical properties and hydrocarbon recovery potential as they play a critical role in reservoir performance. In this paper we have used 3D seismic from the Razzak field in the Western Desert, Egypt, with a specific focus on the Alamein dolomite reservoir. The reservoir holds significance due to its prolific oil-bearing nature, and featuring widespread lateral distribution in the northern Western Desert. Additionally, its contribution to an active Mesozoic petroleum system emphasizes its importance. Using Petrel software, the Alamein top and visible faults were identified, leading to the creation of a structural map illustrating the WSW-ENE axes of the Alamein's structural culminations in the southern part of the horst block. Owing to an extensional force during the Jurassic period with a NE-SW orientation, resulting from rifting, was evident, marked by the formation of normal faults associated with the opening of the Neotethys in the NE-SW direction. In the interpretation of 3D seismic data for Alamein dolomite reservoir, only one major listric normal fault was identified. However, the presence of minor faults or fractures, not easily discernible with conventional seismic techniques, is plausible. To address this, volume attributes were applied to detect subtle changes in seismic properties: (i) the curvature operation calculated the dip and azimuth angles, aiding in identifying structural complexities like faults and fractures, (ii) the maximum curvature value highlighted areas of steeply dipping or folded structures, (iii) Edge detection emphasized sharp boundaries, yet no hidden fractures or minor faults were revealed. The variance attribute yielded limited information, but Ant tracking on the variance cube effectively identified hidden minor faults and fractures. Incorporating the Ant track attribute into FRACPAQ software provided an objective methodology for quantifying fracture patterns, revealing NW-SE-oriented fracture segments in contrast to the WSW-ENE orientation of the major fault. Consequently, seismic attributes will unveil concealed fractures, and the application of FRACPAQ will prove effective in furnishing data on fracture orientation and length statistics.

Key words: FracpaQ; seismic attributes; fractured carbonate; Razzak field

How to cite: Elattar, H.A., Collier, R., and Glover, P. W. J.: Using FracPaQ and seismic attributes to assess seismic scale fractures in carbonate reservoirs, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1674, https://doi.org/10.5194/egusphere-egu24-1674, 2024.

How to cite: Elattar, H., Collier, R., and Glover, P. W. J.: Using FracpaQ and seismic attributes to assess seismic scale fractures in carbonate reservoirs, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1674, https://doi.org/10.5194/egusphere-egu24-1674, 2024.

Revealing the thermal structure of subsurface is crucial for various projects including geothermal energy exploitation, CCS and hydrocarbon exploration. For instance, temperature is one of the key physical underground parameters governing the type of Geothermal systems, whether injected CO₂ remains in supercritical fluid stage and the depth of Golden Zone at where the hydrocarbon accumulations occur. Thus, understanding the temperature and geothermal gradient change in 1D-2D-3D sense indicates sweet spots and helps geoscientists to build more robust models to reduce the risks.

Based on this concept, this study aims to demonstrate the outcomes of a game-changer method which is the conversion of interval velocities into temperatures, thermal conductivities and heat flows by the help of recently proposed empirical relationships. As a case study, Northern Arabian Plate, SE Turkey is selected due to the neglection of thermal conditions in the area. Therefore, oil & gas industry-wide accepted methodologies have been applied to better understand thermal behaviour of the subsurface and how it has been controlled by regional tectonic edifices including large-scale thrust and strike slip faults.

In terms of methodology, as the first step, dynamic bottom hole temperatures of the wells have been converted into static ones by the help of “Temperature Analyser” web application. The converted temperature measurements have been used to generate regional temperature and geothermal gradient maps for every 500 meters. On the other hand, for 3D temperature models, seismic velocities have been converted into temperature cubes after calibration with the converted BHT measurements. Generated temperature cubes have been reflected on seismic sections to display lateral and vertical variations in temperature behaviour. It also allows the detection of meaningful temperature anomalies corresponding to possible fluid content.

The results reveal that abrupt temperature increase on maps directly coincides with the locations of oil producing fields. The same behaviour was noted globally both for hydrocarbon and geothermal fields. The change in temperature trend is also dominated by regional tectonics of the focus area. Large thrust fault systems act as boundaries for thermal anomaly regions while sinistral Mosul Fault Zone displaces and separates high temperature zones in a NW-SE sense. This movement can be easily associated with the Northern slip of the Arabian Plate since the continental collision occurred in the Miocene.

Based on these observations, the workflows and results of this study can be used for detailed investigation of subsurface geology, thermal conditions, and their effect on potential reservoirs for geothermal and CO₂ storage. Workflows used to generate thermal models might allow the development of more efficient sustainable energy projects not only for the Northern sector of the Arabian plate but also for the other regions of the World.

How to cite: Uyanik, A.: Conversion of Interval Velocities into Thermal Models: A Game Changer Method for Subsurface Energy Exploitation Projects , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1739, https://doi.org/10.5194/egusphere-egu24-1739, 2024.

This study is based on unique field data on a 3-year pilot test during which air containing 8 mol% O₂(g) was injected as a cushion gas into a natural gas reservoir, a carbonate-cemented sandstone aquifer located in the Paris Basin (France) [1]. The oxygen was fully depleted several months after injection completion, meanwhile CO₂(g) was detected around 2–6 mol%; the pH decreased from 8 to 6, while reducing conditions shifted to mildly oxidizing ones with increasing concentration of sulfates in equilibrium with gypsum. After the test completion, the long-term evolution of the aquifer was assessed by a 15-year survey. The pH gradually returned to its near initial state and sulfates were reduced by 2 to 3 times. Data on the release of trace metals (Ba, Cu, Pb, Zn) during and after the test were also available.

Multiphase reactive transport models were developed on these field data using the HYTEC reactive transport code in 2D-reservoir configurations [1]. At the short-term scale, modeling focused on the gas-water-rock reactive sequence during the air injection: 1/ depletion of the injected O₂(g) due to pyrite oxidation, 2/ leading to acidity production and dissolved sulfates, 3/ acidity buffering by calcite dissolution, 4/ followed by gypsum precipitation and CO₂(g) exsolution. At the long-term scale, the modeling tackled with the progressive return to the baseline chemistry of the deep aquifer that was 1/ mostly driven by transport processes and 2/ to a lesser extent, slow water/rock chemical interactions.

These field-based models developed at short and long-term could be used as a workflow for other gas storage facilities, e.g. biomethane, compressed air, and CO₂.

[1] Sin, I., De Windt, L., Banc, C., Goblet, P., Dequidt, D. (2023). Assessment of the oxygen reactivity in a gas storage facility by multiphase reactive transport modeling of field data for air injection into a sandstone reservoir in the Paris Basin, France. Science of The Total Environment 869, 161657.

How to cite: De Windt, L., Sin, I., Banc, C., Petit, A., and Dequidt, D.: Short and long-term multiphase reactive transport processes during a pilot test of air injection into a sandstone gas storage facility, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2177, https://doi.org/10.5194/egusphere-egu24-2177, 2024.

Kerogen is typically categorized in three types: type I is associated with lacustrine, type II associated with marine, and type III associated with terrestrial sources, respectively. The Kerogen type is a crucial factor affecting oil-generative properties as it significantly influences the initiation and potential for hydrocarbon generation in source rocks. Geoscientists traditionally use Rock-Eval pyrolysis to determine kerogen types, maturity, and pyrolysis reaction temperature (Tmax), and calculate hydrocarbon potential, essential factors in assessing oil reserves and understanding the oil window. Such method, however, has insufficient resolution and is time-consuming. In this study, we employ a temperature-dependent infrared (IR) spectroscopy method to precisely determine kerogen type, maturity, and Tmax. Specifically, our IR spectroscopy is combined with a numerical analysis model developed for the analysis of various organic matter samples. Through measurements of the IR spectra of samples at different temperatures (Heating-FTIR), we determine the maximum sedimentary burial temperature and the pyrolysis Tmax of kerogen. By applying the conversion formula by Shibaoka & Bennett (1977), (R₀)^a=R^a+bt_I*exp(cT_m), we derive a virtual vitrinite reflectance, which is strongly correlated with our IR spectroscopy results, with insights into the maturation. This Heating-FTIR technique is a valuable tool for petroleum geology, facilitating the assessment of oil potential and maturity. Future refinement of the numerical model and improvement of the instrumentation are required to apply this technique to broader fields, such as sedimentary temperature for ancient geothermal gradient with better understanding of the sedimentary history.

How to cite: Chen, Y.-Y. and Chang, Y.-J.: Evaluation of Oil Source Rocks Using Temperature-dependent Infrared Spectroscopy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2449, https://doi.org/10.5194/egusphere-egu24-2449, 2024.

Recent years have seen the growth of new techniques that combine conventional stratigraphic and observational approaches to characterizing the type, scope, extent, timing and effects of diagenetic processes with petrophysical measurements of their rock microstructure. These Quantitative Diagenetic (QD) techniques can be used to predict post- and pre-dolomitisation porosities and permeabilities as well as trace the pathway of the diagenetically evolving rock through different stages of diagenesis that may turn a low-quality carbonate reservoir into a high-quality reservoir, or vice versa. While these new QD techniques are becoming useful for the characterization of hydrocarbon reservoirs, they are also extremely useful in the characterization of carbonate reservoirs for prospective CCUS use. This paper will briefly explain some of the main approaches to QD including dolomitisation prediction, petrodiagenetic pathways, reservoir quality fields, and Fracture Effect Index (FEI), before examining how they can be used to ensure that the prospective CCUS target reservoir is sufficiently well characterized that effective reservoir modelling can take place, and that the volume, flow and trapping of CO₂ in the reservoir can be effectively monitored. Dolomitisation is known to be affected by the presence of CO₂, with CO₂ dissolving in aqueous pore fluids to form carbonic acid that directly affects porosity through dissolution and indirectly by affecting the dynamics of the dolomitisation process itself. There are two current QD methods for predicting the change in porosity upon dolomitisation. One is affected by both the direct and indirect effects, while the other is only sensitive to the indirect effects. Both the direct and the indirect effects can be plotted on a petrodiagenetic pathway. The presence of fractures is also a key aspect of how injected CO₂ will flow in a CCUS reservoir. The QD parameter FEI describes the change in permeability of a rock concomitant upon a unit change in fracture porosity (i.e., what increase in flow results from a given increase on fracture porosity). This varies depending upon the degree to which fractures are connected and can be extremely useful in predicting the flow of CO₂ within a fractured legacy carbonate CCUS prospect. In summary, QD approaches have the potential to provide those who need to characterise and model carbonate CCUS prospects with new and useful tools.

How to cite: Mohammed-Sajed, O., Rashid, F., Glover, P., Collier, R., and Lorinczi, P.:  Using Quantitative Diagenesis to characterise and understand carbonate CCUS prospects, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3199, https://doi.org/10.5194/egusphere-egu24-3199, 2024.

          It is pivotal to predict the overall composition of subsurface oil and gas reservoirs to assess their fluidity, phase behavior, and recovery potential. Recognizing the significance of n-alkanes as key constituents of mature oil and gas, this study conducted a thermal simulation experiment of gold tube hydrocarbon generation on the source rock of Gulong Sag. The experiment included comprehensive analysis and measurement of the n-alkanes components in a representative sample. Subsequently, an empirical regression evaluation formula was established to evaluate the n-alkanes composition at various maturity stages. Furthermore, a chemical dynamics model for the formation of individual n-alkanes single molecule components was developed and calibrated based on the principles of chemical kinetics. Combined with the stratigraphic burial history and thermal evolution history of the target area, the distribution and evolution characteristics of n-alkanes components in different evolutionary stages of geological conditions can be quantitatively evaluated and predicted. Moreover, the phase behavior of n-alkanes components can be determined based on the evolution characteristics of these components. Experimental results indicate that the methane yield continues to increase with temperature under both heating rates. Additionally, the yield of n-C to n-C initially reaches its maximum with the temperature increase, and subsequently decreases. Furthermore, the hydrocarbon generation characteristics of n-alkanes follow a Gaussian distribution trend. The kinetic results demonstrate that the activation energy of n-alkanes falls within the range of 190-280 kJ/mol, while the distribution of pre-exponential factors is uneven. By considering the geological conditions, it has been determined that the light component in the Gulong Sag is currently experiencing a favorable generation period, whereas the heavy component has reached its peak formation stage, with some undergoing cracking. The oil and gas produced under these geological conditions exist as single-phase unsaturated fluids within volatile reservoirs. The evaluation value of the experimental regression formula, along with the predicted value from the dynamic model, aligns well with the experimental data, providing a solid foundation for the geological application of the model. Therefore, this research serves as a stepping stone towards furthering our understanding of hydrocarbon composition prediction, as well as evaluating phase behavior, mobility, and recovery of underground oil and gas in conjunction with geological conditions. 

How to cite: Bo, S., Xue, H., and Lu, S.: Simulation experiment evaluation and chemical kinetics prediction of the composition of n-alkanes components, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3696, https://doi.org/10.5194/egusphere-egu24-3696, 2024.

Successful exploration of Permian shale gas in the Hongxing area has broadened shale gas exploration in the Sichuan Basin; however, the target layer is newly discovered, and reservoir research, which is key to shale gas exploration and development, is limited, thus restricting the screening and evaluation of the section containing the shale gas target layer. In this study, using organic carbon, whole-rock mineral analysis, scanning electron microscopy, low-temperature nitrogen adsorption, and other experimental methods, and by systematically identifying different lithofacies, we clarified the organic‒inorganic composition and microscopic pore structure characteristics of Permian shales in different phases of the Hongxing area and revealed the main factors controlling high-quality reservoirs and favorable lithofacies types for exploration. The results show that the shale in the study area mainly features six types of lithofacies: high-carbon siliceous shale (RS), high-carbon mixed shale (RM), high-carbon calcareous shale (RC), high-carbon muddy shale (RCM), low-carbon muddy shale (LCM), and low-carbon calcareous shale (LC). Organic pores are mainly present in RS, RM, RC, and RCM, while inorganic pores are dominant in LC and LCM. The pores are dominantly micropores, some mesopores are present, and very few macropores are present. Among them, the degree of micropore development is mainly affected by organic matter (abundance, maturity, and type), that of mesopores is mainly affected by clay minerals, and that of macropores is mainly affected by siliceous and clay minerals. There are obvious differences in the pore structure of different lithologies. The RS has the highest pore volume and specific surface area, with average values of 13.8×10^-3 cm³/g and 21.57 m²/g, respectively, and its pore morphology is ink-bottle type, with pore diameters mainly <10 nm. The storage space of RM, RC, RCM, and LCM is moderate, with low-carbon argillaceous shale (LM) having the lowest.

How to cite: Li, B., Zhou, N., and Lu, S.: Characteristics and factors controlling Permian shale gas reservoirs in the Hongxing area, Sichuan Basin, China, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3700, https://doi.org/10.5194/egusphere-egu24-3700, 2024.

The West Netherlands Basin, which has a long history in exploration as a former prosperous hydrocarbon province, is currently a geothermal hotspot. Being exploited since the 1950’s, most of its oil and gas fields are now in their final phase of production. In the past decade, interest shifted to sustainable energy sources. The geothermal industry in the area is developing quickly, helped by the legacy of the hydrocarbon industry: a wealth of publicly available seismic and well data. Currently, the area has 14 realized, and at least 3 projects in the development phase, with the Late Jurassic Nieuwerkerk Formation being the main target.

Conversely to petroleum systems, in which anticlines are the preferential target for hydrocarbon exploration, synclines are the most suitable sites for geothermal exploration. They offer higher temperatures with respect to the limbs and anticlines, and possible remaining hydrocarbons are not expected to be located inside the central portions of the synclines.

The West Netherlands Basin is a former rift basin that developed during the Mesozoic in the framework of the North Sea rift, and subsequently inverted during the Late Cretaceous. The Nieuwerkerk Formation was deposited during the last major rifting phase. Thus, the thickest packages of its fluvial-deltaic deposits are fault-controlled and commonly located in the synclines. The heterogeneity of fluvial reservoirs causes lateral and vertical quality variations in porosity, permeability and net-to-gross ratios. With the hydrocarbon industry focussing on the stratigraphic highs, there is only limited well data available for the central portions of the synclines.

With reprocessed 3D seismic data, our study uses an image processing approach, coupling traditional amplitude mapping with seismic attributes. This will help to reconstruct the evolution of the fluvial architecture of the Nieuwerkerk Formation over time. By tying the seismic with well data, a better prediction of the quality of the sandy bodies per location can be made. These results can be implemented in de-risking geothermal well planning across fluvial reservoirs in inverted rift basins.

How to cite: Weert, A., Vinci, F., Iacopini, D., van der Vegt, P., Tavani, S., and Ogata, K.: From hydrocarbons to geothermal energy: a case study from the Dutch subsurface, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3864, https://doi.org/10.5194/egusphere-egu24-3864, 2024.

How to cite: Chandra, D., Salgado, B. P., and Barnhoorn, A.: Wave velocities as a proxy to forecast deformation during cyclic loading-unloading in porous reservoir rocks, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4657, https://doi.org/10.5194/egusphere-egu24-4657, 2024.

How to cite: Talukdar, M., Behera, C., Heinemann, N., Miocic, J., and Blum, P.: Cushion gas requirements for hydrogen storage in global underground gas storage facilities, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5508, https://doi.org/10.5194/egusphere-egu24-5508, 2024.

The changes in land use/cover are essential aspects of studying the impact of human activities on the Earth's surface and global transformations. In this study, utilizing the ESRI Global Land Cover data (ESRI land cover 2020) and the China Land Cover Data (CLCD), along with historical imagery from Google Earth, a comparative analysis scheme for land use classification results was designed. The CLCD dataset was updated, leading to the creation of a land use dataset for the Pan-Pearl River Basin spanning from 1985 to 2020. This dataset was then employed for the analysis of land use changes in the Pan-Pearl River Basin over the past 35 years.The results indicate:(1) Among the seven land use types, the most significant changes in area occurred in the following order: build -up land, cropland, forest land, grassland, shrubland, waterbody, and barren. Notably, there was a substantial increase in the areas of build-up land and forest land, while cropland, grassland, and shrubland experienced significant decreases. The waterbody’area showed a slight overall increase trend.(2) The major land use types undergoing changes varied among sub-basins, with the intensity of land use change ranked as follows: Pearl River Delta region(1.9%) > Coastal rivers in southern Guangdong and western Guangxi(0.20%) > Dongjiang River Basin(0.13%) > Hanjiang River Basin(0.12%) > Xijiang River Basin(0.10%) > Beijiang River Basin(0.08%) > Hainan Island region(0.02%).(3) Within the sub-basins of the Pan-Pearl River Basin, the most significant increase was observed in the area of built-up land, exhibiting a continuous expansion trend with a total increase of 12184 km². This increase was primarily due to the conversion of cropland, forest land, and waterbody. The most significant decrease occurred in cropland, with a total reduction of 10435 km², mainly transitioning to built-up land and forest land. The phenomenon of built-up land encroaching on cropland was particularly prominent, especially in the Pearl River Delta region. Forest land also showed a decreasing trend, mainly attributed to cultivation and the encroachment of built-up land. The reduction in grassland area was more pronounced in the Xijiang River Basin, primarily transforming into forest land, cropland, and built-up land. The study reveals that the rapid development of socio-economics and industry, coupled with an increase in residents' consumption levels, serves as the primary driving force behind land use changes in the Pan-Pearl River Basin. Additionally, land use and management policies play a crucial role as driving factors in the region's land use changes. This research aims to provide a scientific basis for formulating policies related to the region's land resources and land management, holding significant importance for preserving ecological balance and fostering sustainable development in the basin.

How to cite: Fan, W. and Yang, X.: Land Use Change Characteristics in the Pan-Pearl River Basin in China from 1985 to 2020, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7216, https://doi.org/10.5194/egusphere-egu24-7216, 2024.

To meet the climate targets outlined in the Paris Agreement, European Green Deal, and the goal of reducing dependence on fossil fuel imports per the REPower EU Action, decarbonizing and reducing energy consumption in the heating and cooling sector is imperative. This sector, a major contributor to household energy use, plays a pivotal role in achieving sustainable energy goals.

Geothermal energy, particularly through geothermal doublets, stands out as an ideal solution for supplying energy for space heating and cooling. However, the inherent risks associated with fluid exchange with the subsurface make it scientifically or politically challenging in certain areas. Addressing this concern, deep borehole heat exchangers function as closed-loop systems, eliminating fluid exchange with the subsurface.

In this study, we explore the feasibility of repurposing existing oil and gas wells in the Northern Netherlands as deep coaxial borehole heat exchangers to provide heat to local communities. Utilizing analytical solutions, we calculate the thermal power output of 365 gas wells suitable for retrofitting. These wells exhibit bottom hole temperatures exceeding 80°C, capable of delivering temperatures above 60°C or thermal powers exceeding 800 kW, depending on flow rate and inflow temperature.

Our analysis includes assessing the proximity of well locations to high-density heat demand neighborhoods within a 6 km radius, facilitating the provision of supply temperatures for future local heat district networks. Notably, heat loss from well to neighborhood generally remains below 2°C, ensuring sufficient heating power supply to nearby residential areas. Several well clusters demonstrate significant heat over-supply, suggesting the potential for transporting excess heat to more distant locations. In cases where heat supply from wells is too low, in particularly in neighbourhoods with very low building efficiency rating (<E), heat pumps can be utilised to supply the needed energy.

Our findings indicate that repurposing existing hydrocarbon wells as coaxial heat exchangers offers a viable option for providing low-carbon heating to numerous residential areas in the Northern Netherlands. However, the geographical distribution reveals that not all high heat demand neighbourhoods have well sites in proximity, underscoring the importance of implementing a diverse heat supply strategy.

How to cite: Miocic, J., Drenth, J., and van Benthem, P.: Reutilising hydrocarbon wells as deep heat exchangers to decarbonise heating in the Northern Netherlands , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7761, https://doi.org/10.5194/egusphere-egu24-7761, 2024.

Digital rock models are becoming an essential tool not only for the modelling of fundamental petrophysical processes, but in specific key applications, such as Carbon Capture and Underground Storage (CCUS), geothermal energy exploration, and radioactive waste storage. By utilizing advanced imaging and simulation techniques, digital rocks provide indispensable insights into the porous structures of geological formations, crucial for optimizing CO₂ storage, enhancing geothermal reservoir characterization, and ensuring the secure containment of radioactive waste. This abstract aims to present new advances using digital rocks to study these pressing environmental and energy challenges.

Estimating the physical properties of rocks, a crucial and time-consuming process in both the characterisation of hydrocarbon, geothermal and CCUS resources, has seen a shift from traditional laboratory experiments to the increasingly prevalent use of digital rock physics. A key requirement of many forms of pore structure image analysis is that they require binary images showing pore-space vs. non-pore space (mineral phases). These are typically obtained by thresholding grey scale SEM or X-ray tomographic images to separate the two phases. In this paper, we have adapted a 2D process-driven MATLAB model to generate synthetic porous media images, laying the foundation for simulating authentic SEM images. The objective of the computational framework outlined in this study is to train a machine-learning model capable of predicting various types of porosity. Drawing inspiration from recent advances in machine learning applied to porous media research, our approach involves the development of deep learning models utilizing Convolutional Neural Networks (CNN). Specifically, we aim to quantitatively characterize the inner structure of the 2D porous media based on their binary images through the implementation of these CNN models. This framework consists of: (i) Generating synthetic porous media images through a process-driven model, (ii) training a neural network that takes a labelled synthetic image as input and gives two types of porosity as output, (iii) whereupon the trained model can be applied to provide types of porosities for new images that are not in the training database. The generated data are divided into training, validation, and testing datasets. The training dataset optimizes CNN parameters for accuracy, the validation dataset aids in hyperparameter selection and prevents overfitting, and the testing dataset evaluates the predictive performance of the trained CNN model.

This research not only advances the understanding of fundamental geological processes but also plays a crucial role in optimizing the utilization of renewable energy sources such as geothermal and contributing to the effective management of carbon capture and storage initiatives.

How to cite: Alwan, W.S., Glover, P. W. J., and Collier, R.: Using machine learning to discriminate between mineral phases and pore morphologies in carbonate systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8307, https://doi.org/10.5194/egusphere-egu24-8307, 2024.

How to cite: Alwan, W., Glover, P., and Collier, R.: Using machine learning to discriminate between mineral phases and pore morphologies in carbonate systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8307, https://doi.org/10.5194/egusphere-egu24-8307, 2024.

Decarbonisation of the European economy represents one of the current challenges to both society and the energy sector. The advancement and further application of carbon capture and sequestration (CCS) technologies are crucial components of the EU’s effort to become climate-neutral by 2050. The success of CCS depends heavily on understanding the present-day stress field to anticipate reservoir and cap rock response to fluid injection. Despite its importance, many proposed carbon storage sites in the North Sea are located in areas with little to no borehole stress data available, presenting a significant challenge.

Within the ACT project SHARP Storage framework, we have addressed this gap by generating a comprehensive earthquake bulletin for the North Sea, revealing spatial clusters of seismic events with the majority of earthquakes with ML < 4. Focal mechanisms of earthquakes are excellent indicators of crustal dynamics, which are essential for assessing the present-day stress field. Therefore, to improve the understanding of the in-situ stress conditions, we created a comprehensive workflow to evaluate focal mechanisms based on data from the North Sea (Kettlety et al., 2023). First, we developed a routine for the seismological bulletin to aggregate the recorded earthquakes from international seismological centres. The following step included retrieval of the waveforms from data centres and quality control routines, which included dead channels check, exclusion of files with significant recording gaps and low signal-to-noise ratio, and corrections of errors in the station XML files. Then, a subset of data traces with sufficient quality was selected for moment tensor computations using a Bayesian bootstrap-based probabilistic inversion scheme (see Heimann et al., 2018). Using existing focal mechanism solutions for the North Sea region, we calibrated our processing routine and then applied it to selected earthquakes (after 1990, M > 3.5) to expand the existing focal mechanisms database.

The newly computed focal mechanism solutions provide valuable insight into the present-day stress field in areas outside the main hydrocarbon provinces and improve the risk assessment of ongoing and future CCS projects. Furthermore, we will release our processing workflow as an open-source package and a new focal mechanisms database of the North Sea to establish a standard processing routine that can be readily utilised for similar seismological studies.

How to cite: Martuganova, E., Naranjo Hernandez, D. F., Kühn, D., and Barnhoorn, A.: Assessing earthquake focal mechanisms in the North Sea for risk mitigation of large-scale CO2 injections, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8973, https://doi.org/10.5194/egusphere-egu24-8973, 2024.

From 2005 to 2020, Canada achieved a 9.3% reduction in green house gas emission (69 Mt CO₂ eq), meanwhile British Columbia witnessed a 5% increase (3.0 Mt CO₂ eq) from 2007 to 2019. Exploiting unconventional oil and gas resources in northeast British Columbia (NEBC) has become the province’s second-largest source of greenhouse gas emissions. In pursuit of a cost-effective and seismic risk-aware approach for carbon emission reduction, this study evaluates the CO₂ geological storage capacity in NEBC with a focus on repurposing existing injection wells for carbon storage.

We particularly emphasize the Montney and Debolt formations. These formations are the main targets of a diverse array of injection wells, including those for hydraulic fracturing, enhanced hydrocarbon recovery, and wastewater disposal. Three trapping mechanisms in the NEBC area are examined: physical and solubility trapping for wastewater disposal wells in the Debolt Formation, and physical and mineral trapping for hydraulic fracturing and enhanced recovery wells in the Montney Formation. Furthermore, we incorporate an assessment of seismic hazards, informed by the latest insights into injection-induced seismicity in NEBC, as a potential indicator of CO₂ leakage risk.

Our findings underscore the favorable conditions of the Debolt Formation with lower seismicity hazard and a substantial CO₂ storage capacity (19.3 Gt; ~284.4 years of CO₂ emissions in BC). Depleted oil and gas reservoirs within the Montney Formation are also deemed suitable for CO₂ storage, estimated at 1671.8 Mt (approximately 24.5 years), particularly in the Upper Montney due to its higher storage capacity and lower seismic risk.

Overall, this research offers an assessment of CO₂ geological storage potential at the formation-scale in NEBC. The emphasis on well suitability and seismic risks effectively bridges the gap between the regional-scale geological assessments and site-scale engineering evaluations. It paves the path for future studies on addressing more practical topics related to the choices of project sites and injection strategies.

How to cite: Yu, H., Wang, B., Kao, H., Visser, R., and Jobin, M.: Storage potential of CO2 by repurposing oil and gas-related injection wells in the Montney Play, northeast British Columbia, Canada, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9206, https://doi.org/10.5194/egusphere-egu24-9206, 2024.

In the development of hydrocarbon fields, it is becoming known that CO₂ injection (which is sometimes done to improve hydrocarbon production) can cause pore blockage and wettability alteration by the promotion of asphaltene deposition. In hydrocarbon reservoirs, the result is poor oil recovery performance during carbon dioxide (CO₂) injection. If CO₂ is being injected into a legacy hydrocarbon reservoir (i.e., one that still contains residual oil) the same process will occur. Once again, the ability of fluid (this time supercritical CO₂) to flow will be impeded, but it is also possible that asphaltene deposition will also reduce the overall pore volumes in which CO₂ could otherwise be stored. In this work, the residual oil distribution and the permeability decline caused by organic and inorganic precipitation after miscible CO₂ flooding and water-alternating-CO₂ (CO₂-WAG) flooding have been studied by carrying out core-flooding experiments at high pressures and temperatures in an artificial three layer system. For simple CO₂ injection during CCUS operations, flooding experimental results indicate that the low-permeability layers retain a large oil production potential even in the late stages of production, which could impede CO₂ emplacement and provide significant heterogeneity, while the permeability decline due to asphaltene precipitation is more significant in high-permeability rocks. In contrast, we found that CO₂-WAG can reduce the influence of heterogeneity on the oil production, but it results in more serious reservoir damage, with permeability decline caused by CO₂–brine–rock interactions becoming significant. In addition, miscible CO₂ flooding has been carried out for rocks with similar permeabilities but different wettabilities and different pore-throat microstructures in order to study the effects of wettability and pore-throat microstructure on formation damage. Reservoir rocks with smaller pore-throat sizes and more heterogeneous pore-throat microstructures were found to be more sensitive to asphaltene precipitation, making these less attractive for CCUS reservoirs. However, rocks with larger, more connected pore-throat microstructures became less water wet due to asphaltene precipitation to pore surfaces, ultimately leading to a lower pore volume in which CO₂ can be stored. Taken together, there may be a case for not simply injecting CO₂ in CCUS operations, but alternating the CO₂ injection with injection of water in order to stabilise CO₂ flow and reduce formation damage by asphaltene precipitation.

How to cite: Wang, Q., Paul, G., and Piroska, L.: Quantifying flow reduction during injection of CO2 into legacy hydrocarbon reservoirs for CCUS, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9509, https://doi.org/10.5194/egusphere-egu24-9509, 2024.

Though global energy needs continue to grow, fossil fuels, and their associated CO₂ emissions, are increasingly being opposed as our main source of energy. Instead, to achieve net zero greenhouse gas emissions goals, we are currently transitioning to more sustainable sources of energy, such as solar and wind power and geothermal energy, coupled with storage of waste, such as CO₂. However, these new technologies come with their own challenges, as they continue to rely on (re-)use of the subsurface landscape. The intermittency of solar and wind power will require storage of renewably generated electricity. Hydrogen fuel has been marked as a potential energy carrier, enabling us to store large quantities of energy for prolonged periods of time, such as required to supply large industries or communities during winter months. To store this hydrogen fuel, the subsurface offers the largest storage space available, such as in (offshore) depleted hydrocarbon fields, but reproduction of the stored fluid is crucial. Geothermal energy production will require the extraction of hot fluids from depth and will often be performed in populated areas, close to the consumers, meaning that phenomena such as surface subsidence and induced seismicity are highly undesirable. The safe storage of CO₂ for thousands of years also entails fluid injection, but containment is of vital importance to keep the CO₂ out of our atmosphere. So though we have a vast history of exploitation of the subsurface through the oil and gas industry, which we can and should build upon, these new sustainable energy developments also pose their own, new challenges. While fluid production changes the physical equilibrium of the system, these new uses will also impact the chemical equilibrium through the injection of new fluids. Furthermore, containment and safety play an even bigger role than before to ensure the longevity of these new subsurface operations. In this contribution, I will outline what the challenges are that we are facing and how geoscientists can contribute to solving these challenges, across all areas from rock physics, geochemistry and hydrology, to sedimentology, structural geology and policy.

How to cite: Hangx, S.: Same same but different: the scientific challenges when re-using the subsurface for sustainable energy developments, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12486, https://doi.org/10.5194/egusphere-egu24-12486, 2024.

In the context of Carbon Capture and Storage (CCS), the porosity of potential storage formations is a critical factor. Our study explores this aspect using computed tomography (CT) to assess how different scanning resolutions impact the accuracy of porosity measurements. We employed three CT systems - Geotek RXCT (resolution ~20-150 μm), Bruker 1272 (resolution ~5 μm), and DELab μCT-100 (resolution ~9 μm) - to scan sandstone cores of varying porosities. The aim was to identify an optimal scanning resolution that balances detail with practicality for CCS evaluations.

This research addresses the challenges in high-resolution CT scanning, such as denoising effects that can alter accuracy, and the complexities of thresholding segmentation across various systems. Additionally, we examined the partial volume effect, crucial for interpreting pore sizes and distributions accurately.

Our preliminary results suggest that scanning resolution significantly affects the perceived porosity. Different resolutions uncover diverse aspects of pore structure, highlighting the importance of choosing an appropriate resolution. Advanced image processing techniques, including effective denoising and accurate thresholding, are vital for reducing errors in porosity measurement.

The study provides valuable insights into the use of CT scanning for CCS applications, emphasizing the need for a balanced approach in resolution selection and sophisticated image processing. These findings are instrumental in enhancing the reliability of geological evaluations for potential CCS sites, contributing to the broader efforts in carbon storage and climate change mitigation.

How to cite: Huang, J.-J. S., Liou, Y.-M., Kioka, A., and Yang, T.-R.: Exploring the Relationship between CT Scanning Resolutions and Sandstone Porosity for CCS Applications, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12846, https://doi.org/10.5194/egusphere-egu24-12846, 2024.

Hydrogen sulfide (H₂S) is a harmful gas associated with oil and gas, which seriously affects the safety and effective exploitation of oil and gas, so it is important to evaluate the origin and distribution of hydrogen sulfide effctively. H₂S rich oil and gas reservoirs were found in lacustrine carbonate rocks of Es₄, Dawangzhuang area, Chezhen Sag. In order to clarify the formation mechanism and enrichment law of H₂S in this area, the geochemical characteristics of natural gas, formation water, elemental characteristics of reservoir solid bitumen, and sulfur isotope characteristics of kerogen, salt-rock and crude oil are analyzed comprehensively. It is concluded that H₂S in Dawangzhuang area is caused by thermochemical sulfate reduction (TSR). H₂S in Dawangzhuang area is generated from the northern deep depression zone and migrated to the upper submember of Es₄ carbonate reservoir in the study area through the successor fault activities during and after Guantao accumulation period. This understanding will provide reference for the future development of sulfur-rich oil and gas reservoirs in Dawangzhuang area and the avoidance of high-yield H₂S risk.

How to cite: Han, D., Dong, C., and Ma, P.: The formation mechanism and enrichment patterns of H2S in Es4 of Dawangzhuang area, Chezhen Sag, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13736, https://doi.org/10.5194/egusphere-egu24-13736, 2024.

In recent years there has been rapid development of nanoparticles (NPs). Nanoparticles can be used both as a probe into restricted spaces, such as the pores within a reservoir rock, and as tools for altering wettability or deliberately blocking pore throats to enhance fluid movement in less connected pores. Silica nanoparticles can have functional surfaces allowing them to react specifically to oils or water. Nanoparticles can be used to enhance oil production by releasing oil on mineral surfaces and improving fluid flow. However, they also have the potential for improving CO₂ flow in CCUS reservoirs while enhancing the pore volume available for CO₂ storage. In this paper we evaluate the performance of different non-functionalised and functionalised nanoparticles for enhancement of oil production, CO₂ emplacement and gas flow. Different forms of silica NPs have been made, either unfunctionalized, or functionalised with branched amino-based polymer (hydrophilic) or a silane-based agent (hydrophobic). Their stability has been characterised using a range of laboratory methods. The microscopic performance of the nanoparticles has been measured using contact angle measurements. Their ability to enhance oil production and CO₂ emplacement has been tested using imbibition and drainage experiments. 

The contact angles, measured in the presence of brine, no modified silica NPs, branched amino-based polymer (hydrophilic) modified silica NPs and silane-based agent (hydrophobic) modified silica NPs showed contact angle values of approximately 110°, 116°, 124°, and 136°, respectively. These results show that introduction of nanofluids led to a change in substrate wettability from water-wet to strongly water-wet. Notably amongst the tested nanoparticles the Silane-based NPs demonstrated the highest hydrophilic surface. The spontaneous imbibition tests conducted on various sandstone cores revealed that silane-based NPs yielded the highest oil recovery rates among the tested NPs. Specifically, these nanoparticles showed an approximate 12% and 50% enhancement in oil recovery compared to non-modified silica nanoparticle, and branched amino-based polymer (hydrophilic) modified silica NPs. In summary, nanofluids have been shown to substantially improve the wettability alteration of the rock surface from oil-wet to water-wet, which can lead to improve the volume and flow characteristics of legacy CCUS prospects. Our future plan is to investigate the enhancement of carbon dioxide (CO₂) solubility in brine through the utilization of the prepared nanoparticles, with the objective of advancing carbon capture technologies.

How to cite: Tliba, L., Hetnawi, A., Sagala, F., Menzel, R., Glover, P., and Hassanpour, A.: Characterising functionalised nanoparticles for improving fluid flow for CCUS in legacy hydrocarbon reservoirs , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13835, https://doi.org/10.5194/egusphere-egu24-13835, 2024.

TRANSGEO is a regional development project that aims to explore the potential for producing sustainable geothermal energy from abandoned oil and gas wells in central Europe.  Composed of 11 partner organizations and 10 associated partners in 5 countries, TRANSGEO is developing a Transnational Strategy and Action Plan to address this technical and economic opportunity.  Our primary objective is to support rural communities and industries in the energy transition by providing tools and information that highlight sustainable redevelopment priorities and opportunities.

To reach this objective and promote the switch from fossil fuels to green energy, TRANSGEO is developing reuse procedures for five different geothermal technologies and validating them via numerical modelling, to assess their performance in repurposing existing hydrocarbon infrastructure and determine the optimal reuse conditions and configurations.  The five geothermal technologies are Aquifer Thermal Energy Storage, Borehole Thermal Energy Storage, Deep Borehole Heat Exchangers, Enhanced Geothermal Systems, and Hydrothermal Energy production.  The modelling studies focus on reference sites in our study areas, the North German Basin, the South German Molasse Basin, the Vienna Basin, and the Pannonian Basin.  Comparison of varying wellbore and reservoir parameters in the numerical modelling studies will provide input to a new online well assessment tool which will be available publicly to determine well suitability and guide planning for future reuse projects.  The online tool will be informed by a database of abandoned wells in Austria, Croatia, Germany, Hungary, and Slovenia and will include local reference data, such as geology, topography, heat demand, and utilities.  This will facilitate well reuse by matching candidate wells with local energy demand and heating networks.  Additional work on socio-economic and policy analyses will provide financial and liability information for the 5 different geothermal technologies, across the project countries.  Finally, the partnership will propose a legal policy and incentive framework to facilitate and expand reuse of abandoned wells for geothermal energy production and storage across central Europe.

TRANSGEO is co-funded by the European Commission’s Interreg CENTRAL EUROPE programme.

How to cite: Hofmann, H., Friddell, J., Sass, I., Höding, T., Sieron, K., Svetina, M., Hölzel, M., Philipp, R., Márton, G., Borkovits, B., Bődi, K., Višnjić, A., Kurevija, T., and Vogrinčič, B.: TRANSGEO - Transforming abandoned wells for geothermal energy production, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14959, https://doi.org/10.5194/egusphere-egu24-14959, 2024.

Geological characterization of the “Fonts-Bouillants” helium discovery - France

Russier E^1,2, Géraud Y², Hauville B¹, Tarantola A² ,Beccaletto L³ and Diraison M¹

¹ 45-8 ENERGY, France

² GeoRessources, University of Lorraine, France

³ BRGM, F-45060, Orléans, France

ABSTRACT

Helium is essential for the manufacturing of many of our daily commodities such as optical fibres, computers or cell phones (semiconductors and processors), medical use (MRI scanners) or in other more specific applications such as airlifts, leak detection, gas chromatography or diving. Nowadays, Europe imports 100% of its helium needs from overseas and is facing regular shortages, reason why 45-8 Energy embarked five years ago on helium exploration and production in Europe.

Helium is a noble gas mostly coming from the natural radioactive decay of Uranium and Thorium contained in the crust and the basement. Its migration and accumulation are strongly linked to a vector fluid that can be CO₂, N₂, CH₄ or water. Helium and its vector fluids are then trapped and sealed in a rock reservoir.

The Fonts-Bouillants area is located at the southern edge of the Paris Basin at the vicinity of the French Massif Central and Limagne rift. The 45-8 Energy project aims to jointly produce He and CO₂ from a gas which is naturally seeping through the major Saint-Parize fault (SPF).  Geological origin and migration pathway of He are therefore key questions to define the exploration guide, in particular to locate production wells to produce the seeping gas and process it. A multidisciplinary approach involving geology, geophysics, petrophysics and geochemistry has therefore been deployed.

Because geological context was hardly documented in this area, a wide range of geophysical data were acquired or reprocessed and coupled with field geology to build a regional geological model. The initial geological model was considerably updated and a hidden and thick Late Palaeozoic depocenter was especially highlighted below the Mesozoic series. Well data in nearby analogous basins as well as outcrops enabled rock collections to conduct petrophysical and geochemical characterization. The main reservoirs discovered currently are in Triassic and Jurassic sandstones, and fault like Saint-Parize fault acted as barrier and drain. 

Our outcrops petrophysical and geochemical study highlight the importance of Late Palaeozoic basin for the helium system:

• As a potential rock source, with higher U-Th concentrations (3-13.5, 8-24 ppm) than typical crustal U-Th concentrations (1.8 and 7.2 ppm, [1]).
• As a potential migration pathway and reservoir, with sandstones and conglomerates porosity higher than 20% and permeability higher than 100 mD.

Finally, gas sampling was performed in local natural springs, but also during well testing conducted in shallow boreholes which have encountered gas bearing reservoirs in the Mesozoic along the SPF. Helium generation system was modelled with geochemical data from the rocks and the fluids and from the volumetric capacity of the Palaeozoic basin.

Keywords: Helium exploration, Geophysics, Petrophysics, Geochemistry

Themes: Helium exploration

References:

[1] Krauskopf, K. B., & Bird, D. K. (1967). Introduction to geochemistry (Vol. 721). McGraw-Hill New York.

How to cite: Emma, R., Yves, G., Benoît, H., Alexandre, T., Laurent, B., and Marc, D.: Geological characterization of the “Fonts-Bouillants” helium discovery - France, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16266, https://doi.org/10.5194/egusphere-egu24-16266, 2024.

Natural gas storage is currently considered as one key pillar of the EU strategy to ensure security of energy supply. In view of CH₄ storage, Oldenburg [1] demonstrated in a theoretical study that using CO₂ as cushion gas instead of CH₄ has the advantage of increasing natural gas storage capacities of geologic reservoirs by up to 30 %. This is due to CO₂ undergoing a significant density change when its’ critical pressure is exceeded during CH₄ injection. Kühn et al. [2] investigated a comparable scenario with CH₄ gas storage in a closed cycle with CO₂ in one reservoir to temporarily store and reuse wind and solar energy. However, the potential qualitative degradation of the stored CH₄ due to mixing with the CO₂ cushion gas has not yet been sufficiently addressed in terms of the impact of the modeller’s choice of diffusion coefficients. Hence, the present study focuses on a quantitative assessment of the mixing behaviour of CH₄ and CO₂ under consideration of dynamic binary diffusion coefficients in a reference numerical simulation benchmark [1,3]. The TRANSPORTSE numerical simulator [4,5] is used with dedicated measures to mitigate the initially high numerical dispersion, introduced by the benchmark’s relatively coarse grid discretisation. The simulation results show that the mixing region is substantially reduced if dynamic binary diffusion coefficients are applied instead of a global constant for both gas components. Consequently, it is demonstrated that previous numerical assessments of natural gas storage with a carbon dioxide cushion gas overestimate the simulated CH₄-CO₂-mixing area, and thus the calculated mixing losses. Hence, combined gas storage of CH₄ and CO₂ is more efficient than expected so far.

[1] Oldenburg, C. M. (2003) Carbon Dioxide as Cushion Gas for Natural Gas Storage. Energy Fuels 17(1), 240−246. https://doi.org/10.1021/ef020162b

[2] Kühn, M., Nakaten, N. C., Streibel, M., Kempka, T. (2014): CO2 Geological Storage and Utilization for a Carbon Neutral “Power-to-gas-to-power” Cycle to Even Out Fluctuations of Renewable Energy Provision. Energy Procedia, 63, 8044-8049. https://doi.org/10.1016/j.egypro.2014.11.841

[3] Ma, J., Li, Q., Kempka, T., Kühn, M. (2019) Hydromechanical Response and Impact of Gas Mixing Behavior in Subsurface CH4 Storage with CO2-Based Cushion Gas Energy & Fuels 33 (7), 6527-6541. https://doi.org/10.1021/acs.energyfuels.9b00518

[4] Kempka, T. (2020) Verification of a Python-based TRANsport Simulation Environment for density-driven fluid flow and coupled transport of heat and chemical species. Advances in Geosciences, 54, 67-77. https://doi.org/10.5194/adgeo-54-67-2020

[5] Kempka, T., Steding, S., Kühn, M. (2022) Verification of TRANSPORT Simulation Environment coupling with PHREEQC for reactive transport modelling. Advances in Geosciences, 58, 19-29. https://doi.org/10.5194/adgeo-58-19-2022

How to cite: Kempka, T. and Kühn, M.: Geologic CH4 storage with CO2 cushion gas: using dynamic binary diffusion coefficients instead of a global constant in numerical simulations is more precise and results in lower mixing losses, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17184, https://doi.org/10.5194/egusphere-egu24-17184, 2024.

Since the end of the XIX century, many wells have been drilled worldwide for both Oil & Gas exploration purposes. Most of them are now abandoned and subjected to mining closure because exhausted or sterile. In the new epoch of energy transition scenario, the possibility to adapt and reuse these existing boreholes to exploit geothermal energy seems very promising. In fact, considering that approximately 40% of the total costs for a new geothermal project are devoted to drilling activity, the possibility of repurposing abandoned oil and gas wells offers a wide range of applications and exploitation of underground heat uses. The drilled borehole available data (e.g., underground temperature, lithology) provide helpful information about the sub-surface reservoirs, reducing the mining risk level, and wells allow direct access to the sub-surface heat energy. However, to develop a commercially viable geothermal power/thermal generating system, one must consider several factors, i.e., available prospecting, drilling and reservoir technologies, energy costs in the area, and resource durability.

This research aims to analyze the potential and feasibility of deep closed-loop systems solutions for heat and power energy production in Italy, in areas characterized by both normal and anomalous geothermal gradients and the distribution of available abandoned oil and gas wells. A prominent result is the development of a workflow leading to the feasibility assessment of deep closed-loop systems development, based on the identification of suitable abandoned O&G wells through the geological and thermal underground characterization and wells construction characteristics (diameter, depth, borehole material). Furthermore, a sensitivity analysis of the main parameters affecting most of the retrofitting of abandoned wells for geothermal purposes is performed thanks to thermal FEM modelling.

Finally, identifying the possible end-users in a suitable case study area, this research work provides preliminary insights into the quantity of thermal energy and electric power that this technology could produce.

How to cite: Facci, M. and Galgaro, A.: Numerical sensitivity analysis of energy performance of geothermal deep closed loop heat exchangers derived from the reuse of abandoned oil and gas wells, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17674, https://doi.org/10.5194/egusphere-egu24-17674, 2024.

The dynamics of sedimentary basins is a complex combination of synchronous generally non-linear processes. In these natural systems, fluids migration and associated transfers play a fundamental role, even more so as they represent resources that are or may become essential for human societies. One way of assessing the potential of sedimentary basins is to model their past behaviour numerically.

Basin models have been developed since the 1990s for the needs of the oil industry, with the initial aim of assessing the thermal history, i.e. the maturation and expulsion of hydrocarbons from source rocks with variable kinetics and initial composition. These models are used for hydrocarbon prospect assessment in a wide range of sedimentary basins. They have evolved with the integration of the simulation of compaction mechanisms and fluid migration by Darcean single-phase or multi-phase flows. Still with an operational objective in mind, one of these models has been extended to simulate the transport of thermal energy and chemical elements in fluids, thereby helping to assess the geothermal and large-scale storage potential of a basin. The explicit representation of faults and unconformities, as well as the calculation of seal or reservoir formation fracturing as a function of fluid pressures, enables the plumbing system to be represented on a basin scale. In this network of drains, single- or multiphase fluids carrying compounds can interact with the rocks, according to the principles of reactive transport. Some of these simulations are being experimented using AI techniques. In these digital experiments, elements tracking could be a true added value for basin’s dynamics understanding.

A coupled simulation of this kind, combining conductive and advective thermal physics, mechanics (particularly of porous media), the hydraulics of multiphase fluids in porous media, chemistry of reactive transport and even the impact of bioactivity on basin’s fluids, representing geological processes in the subsurface on a large scale, makes it possible to quantify mass and energy transfers in the past. The result is a physically balanced model of the current spatial distribution of pressure, stress, temperature, mass, solid or fluid elements.

These results can be useful both in economic applications for first-order assessment of the resources of any sedimentary basin and in the scientific field for defining the boundary conditions of more specialised models. Initial experiments demonstrating the use of multiphysics models on a basin scale for CCS applications and geothermal energy assessment will be shown.

How to cite: Gout, C., Cacas-Stentz, M.-C., Traby, A., and Collard, N.: Modelling dynamics of sedimentary basins: using geological history to predict subsurface activities at large-scale, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18605, https://doi.org/10.5194/egusphere-egu24-18605, 2024.

With the advancement of exploration theory and technology, deep and ultra-deep carbonate rocks have gradually become an important new field for the development of oil and gas resources. High-quality carbonate reservoirs have become the focus of attention for oil and gas exploration and research in deep and ultra-deep fields. The Tarim Basin is the largest intracontinental oil and gas basin in China. The thick carbonate strata developed in the Lower Paleozoic are the main layers for oil and gas exploration, and the Ordovician carbonate strata are the main oil and gas producing layers. The predecessors have studied the tectonic evolution, sedimentary background and rock types of the Ordovician in the Tarim Basin. Combined with the analysis of the sedimentary thickness, lithology distribution and seismic profile structure of the Early Ordovician, it is believed that the Lower Ordovician sedimentary period inherited the Cambrian sedimentary pattern and transformed it into a gentle slope sedimentary background with a 'uplift-sag 'pattern, with obvious differentiation. Under the sedimentary background of the gentle slope of the Penglaiba Formation, the three paleo-uplifts of southwestern, northern and central Tarim are inherited geomorphological highs, and the inner gentle slope tidal flat facies is developed. The thickness of the stratum is obviously thinner, and it is mainly developed to represent the tidal flat environment. The periclinal part around the paleo-uplift is the middle gentle slope, which is characterized by dolomite and limestone interbeds. The proportion of granular rocks is high, which is a favorable development area for granular beaches. In this study, the deep drilling cores of the Lower Ordovician Penglaiba Formation in the central Tarim Basin were taken as the key research object, and the lithofacies, reservoir characteristics and dominant reservoir control factors of dolomite reservoirs were systematically analyzed by using macro-micro, qualitative-quantitative reservoir petrology analysis methods. Through research, it is clear that the rock types of the Lower Ordovician Penglaiba Formation in the central Tarim Basin are mainly crystalline dolomite and ( residual ) granular dolomite, and also contain a small amount of limestone, siliceous rocks and transitional rocks. There are various types of reservoir space, mainly including non-fabric selective dissolution pores, intercrystalline pores and various fractures. Combined with previous studies on the genesis and diagenetic evolution of the Lower Ordovician dolomite in the Tarim Basin, it is considered that the development of high-quality dolomite reservoirs in the Lower Ordovician Penglaiba Formation in the central part of Tarim Basin is controlled by many factors. It is the result of a combination of favorable sedimentary facies belts, short-term sea-level changes, exposure and dissolution, early dolomitization, and late tectonic hydrothermal adjustment and transformation.

How to cite: Li, X. and Xu, Q.: Development characteristics and controlling factors of deep dolomite reservoirs of Lower Ordovician in Tazhong area, Tarim Basin, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20142, https://doi.org/10.5194/egusphere-egu24-20142, 2024.

Seismic data integration plays a pivotal role in enhancing the capabilities of geological modelling

software. Our current research focuses on the improvement of seismic interpretation tools within the

PZero software in the framework of the Geosciences IR project lead by the Italian Geological

Survey GitHub - andrea-bistacchi/PZero. The objective is to seamlessly incorporate seismic data

into the geological modelling workflow, enabling more comprehensive and accurate models of

subsurface structures.

The initial phase of our work involved using various libraries to import and analyze seismic

datasets, either 2D or 3D within the PZero framework. We have successfully achieved the

importation of SEGY files into PZero, marking a significant milestone in our efforts. Integrating

seismic data is a crucial step that sets the foundation for constructing detailed geological models,

allowing us to enhance our understanding of subsurface geological features.

Soon, our research trajectory aims to develop advanced algorithms for stochastic simulation tailored

explicitly for modelling clastic sedimentary alluvial plains. The ongoing work includes developing

advanced stochastic simulation algorithms tailored for modelling clastic sedimentary environments,

relevant to both conventional energy resources and emerging sustainable energy storage solutions.

These advancements in seismic data integration and simulation within PZero will significantly

contribute to the field of reservoir modelling. They provide a robust framework for predicting the

behavior of subsurface energy storage systems, which is pivotal in the transition to a low-carbon

energy future.

How to cite: Hussain, W. and Bistacchi, A.: Advancements in Seismic Data Integration and Stochastic Simulation for Geological Modeling in PZero, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22365, https://doi.org/10.5194/egusphere-egu24-22365, 2024.

Transient Electromagnetic (TEM) methods are widely used in near-surface geophysical exploration. Traditional ground-based TEM systems utilize large transmitter loops (25x25 to 50x50 m²) to investigate depths between 200 and 300 meters, yielding 15-20 soundings per day. To enhance efficiency in shallower investigations (0 - 100 m), we introduce a compact TEM system with a small coil setup for rapid deployment and mobility, increasing data collection rates along extensive transects.

The novel system comprises a 3x3 m transmitter loop with two turns and an equivalently sized offset receiver loop with four turns, separated by 10 m to minimize coil coupling and ensure unbiased signals. Operating as a single-moment setup, it achieves a peak current of 5 Amp or 10 Amp, turning off in approximately 7 µs. Unbiased measurement begins at 10 µs post turn-off, extending to a late gate of 3 ms. Both transmitter and receiver are integrated into a portable unit powered by lightweight lithium-ion batteries. A dedicated mobile application for Android and iOS devices controls the system, facilitating real-time monitoring of data curves and system parameters like current and temperature.

With this system, two people can collect a 400 m profile in under 60 minutes, significantly faster than Electrical Resistivity Tomography (ERT) methods. The presentation will cover the system's layout, operational methodology, depth capabilities, and validation against the Danish National TEM Test Site. Comparative analyses will underscore its efficiency and effectiveness in aquifer layer mapping, offering a compelling alternative to traditional ground-based systems.

How to cite: Maurya, P., Auken, E., and Bording, T.: A small coil transient electromagnetic system for quick subsurface mapping , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2809, https://doi.org/10.5194/egusphere-egu24-2809, 2024.

Controlled-source audio-frequency Magnetotellurics method (CSAMT) partially overcomes the drawbacks of weak natural field signals. However, substantial interference is an inevitable part of field surveys in practice, which negatively impacts signal quality. We require new denoising techniques since traditional techniques, such as Fourier transformation, which compute apparent resistivity directly from frequency-domain data, are insufficient in our situation. CSAMT denoising research is currently lacking, nevertheless. This research proposes the use of long short-term memory (LSTM) neural networks to denoise CSAMT signals in the time domain, given their good performance in processing Magnetotelluric (MT) data as shown by prior studies. We seek to directly extract the desired frequency signal for denoising from the time series data, in contrast to conventional denoising techniques. Since noise and target frequency signals are mixed together in MT data, the only way to suppress noise is to find the characteristics of the noise in the time series. CSAMT, on the other hand, differs from MT in that it uses an artificial transmitting source and fixes the valid signal frequency within a temporal window. This makes it possible to extract target frequency signals directly without taking into account the intricate properties of noise. In order to complete the noise suppression job, we created a neural network in this study that is based on bidirectional LSTM. This method was able to partially handle the difficulty of denoising when the data's SNR falls below 0 dB and, on average, enhance the signal-to-noise ratio (SNR) of CSAMT data by roughly 20 dB after executing both simulated and measured data testing.

How to cite: An, Z., Xu, B., Han, Y., and Ye, G.: Time-domain denoising of CSAMT data base on long short-term memory, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5979, https://doi.org/10.5194/egusphere-egu24-5979, 2024.

Coal-fired power plant requires huge storage of coal. During the storage of coal, heat is accumulated inside the stock piles and eventually results in the self-combustion or coal fire, which is a very serious problem in the fuel management and environmental aspect of the power plant facilities. To detect and forecast the coal fire, various methods had been suggested but there are no proven early warning technology until today. Since the resistivity of the coal is strongly affected by temperature, we suggested the ERT (Electrical Resistivity Tomography) monitoring technology to identify the heat accumulation inside the coal stock pile, which can eventually provide an early warning method of coal fire in the power plant facilities. To prove the technology, we prepared a small scale coal stock pile and electrodes were placed on the bottom of the stock pile. In the inside of the coal pile, temperature was continuously increased by using heating tools and ERT monitoring data were acquired for a few days until real coal fire take place on site. The whole ERT monitoring data were processed and we tried the 4D inversion to obtain changes of 3D resistivity distribution with temperature changes. In the 4D inversion results, we could identify the systematic change of resistivity values due to the heating process. Although resistivity is increased in the very early heating stage, increased resistivity is evident with the increase of coal temperature until self-combustion of coal. Therefore, we could prove that 4D ERT monitoring technology is a very promising method to detect and forecast the coal fire in the power plant facility.

How to cite: Yi, M. J., Jeong, S., and Shin, S.: Early Detection of Coal Fire inside the Coal Stock Pile by 4D ERT Monitoring, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7179, https://doi.org/10.5194/egusphere-egu24-7179, 2024.

Imaging the structure and state of the subduction channel in the Himalayan Orogenic Belt is important for understanding the deformation of the continental collision front. The high-resolution three-dimensional electrical model revealed that the electrical properties of the subduction channel north of Mount Everest are not continuous. Rather than pipeline flow, crustal thickening, and thermal transport from the subduction front, the conductors above the Main Himalaya Thrust interface are likely caused by local dehydration of the subducting material or bending of the Indian crust. North of Mount Everest, the long-distance migration and high differentiation of fluids along the Southern Tibetan Detachment System (STDS) may be attributed to the high temperature and volatiles from the U-shaped chamber underneath the STDS, as well as the pore-fluid pressure from the stress concentration of the fluidized subduction channel.

How to cite: Wang, G., Fang, H., and Zhang, Y.: Tectonic response of the subduction channel in central Himalya revealed by magnetotelluric data north of Mount Everest, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7831, https://doi.org/10.5194/egusphere-egu24-7831, 2024.

Soil and groundwater contamination has been widely concerned because of its impact on industrial, agricultural production, and even human health. Accurate delineation of contaminant distribution is the basis for successful remediation strategies. Traditional drilling based methods are costly and less efficient. Geophysical methods, particularly electrical resistivity (ERT) and induced polarization (IP), are sensitive to soil and groundwater contamination and have been proven very effective. However, there were still some pressing issues to be resolved, such as IP mechanism of contaminant, data acquisition, inversion strategies and monitoring system. In this study, we proposed the conceptual model of IP response for LNAPLs in-situ remediation process based on laboratory columns and sandboxes IP measurements, and quantified the effect of contaminant removal on IP parameters. In addition, the IP data acquisition method were improved for contaminated site surveys, doubling the detection depth and significantly increasing the IP data quality. Moreover, we propose a refined structure-constrained method that updates the smooth weights of all eight elements surrounding a boundary element using three different magnitudes. Combined with the joint interpretation of multisource data, detection accuracy was improved and the number of boreholes was reduced. We have applied ERT and IP techniques to more than 30 contaminated sites and proved their effectiveness.

How to cite: Meng, J., Xia, T., Ma, X., Zhao, R., and Mao, D.: Characterization of contaminated site using electrical resistivity and induced polarization methods, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9430, https://doi.org/10.5194/egusphere-egu24-9430, 2024.

The Badain Jaran Desert, located in the western part of the Inner Mongolia Autonomous Region in China, distinguishes itself from typical deserts by its abundance of lakes and rich groundwater reserves. At the Badain Jaran Desert, 153 magnetotelluric sounding stations have been explored to perform one-dimensional and three-dimensional inversion analyses of the collected magnetotelluric dataset. The results of one-dimensional inversion at each sounding station, where the top interface of the first underground low-resistivity layer is less than 400 meters, were used to build a map of the potentiometric surface level of the study area. This map aligns closely with the findings from hydrological surveys. The three-dimensional resistivity model indicates the existence of a conductive layer at the deep of 2-3 km, interpreted as a sandstone-confined aquifer, located between the mountain areas surrounding the Badain Jaran Desert and its clusters of lakes. 
Moreover, there is an almost vertical conductive zone underneath the lake cluster, which is interpreted as the discharge area of the confined aquifer. This zone is related to the upward flow of deep groundwater through fractures, replenishing both the lakes and the shallow groundwater, while the surrounding mountainous regions of the desert act as the recharge areas for this confined aquifer. Finally, an estimation of the volumetric percentage of saline fluid in the confined aquifer was derived based on the electrical conductivity model of pore-fluid saturated sandstone, yielding the saline fluid content that meets the resistivity/conductivity range conditions of the confined aquifer.

How to cite: Yi, X., Ye*, G., Jin, S., Wei, W., and Zhang, Y.: Groundwater Recharge Mechanisms in the Lake Clusters of the Badain Jaran Desert and the Salinity of Confined Aquifers Based on the Electrical Conductivity Model of Pore-fluid Saturated Sandstone, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15176, https://doi.org/10.5194/egusphere-egu24-15176, 2024.

The region Lusatia in northeastern Germany, which is located about 100 km south of Berlin, is strongly affected by over a century of both former and on-going opencast lignite mining. Although, there is an abundance of borehole data from former excavation surveys both varying data quality and heterogeneous coverage is a challenge for deriving spatially continuous subsurface properties. To overcome these obstacles we combined airborne geophysical investigations with borehole data. Different machine learning-algorithms (Random Forest and K-means) are used to determine spatially and depth-related insights into the variability of geological and hydrogeological characteristics. An aeroelectromagnetic (AEM) survey was carried out in summer 2021 using BGR’s (German Federal Institute for Geosciences and Natural Resources) helicopter, which covered flight lines of 1680 km in an area of about 200 km². First results show that the machine learning approach can predict fine-grained sediments (clay and silt) in untrained areas and can distinguish between clusters of mining-affected regions and undisturbed ones. The results of the study will be further used to improve the parameterization of existing regional groundwater flow models to address challenges of water allocation in the region of Lusatia.

How to cite: Schönfeldt, E., Cortes Arroyo, O., Fahle, M., Siemon, B., Janetz, S., and Nixdorf, E.: Insights into geological and hydrogeological characteristics using airborne geophysical investigations of former opencast lignite mining areas, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15575, https://doi.org/10.5194/egusphere-egu24-15575, 2024.

At GTK we are currently developing the entire workflow of the controlled source EM (CSEM) method, ranging from data acquisition to time series processing to modelling and inversion. Part of this work is the development of a 3D modelling and inversion framework, which is mostly done within the DroneSOM project. The flexible implementation allows not only for modelling and inversion of semi-airborne drone EM data, but also land-based CSEM/MT data. The forward problem is solved using the finite element method on hexahedral meshes. We separate forward and inverse mesh using octree mesh refinement. This helps in solving the trade-off between the required accuracy in the forward modelling and computational cost. It is also a great tool to combine different multiresolution EM data (e.g., CSEM and MT) in a single comprehensive inversion framework. This work will focus on first applications of land-based CSEM and (CS)MT.

In 2022 we collected controlled source MT data using a grounded electric dipole transmitter along the Koillismaa ultra-mafic intrusion in North-Eastern Finland. Despite transmitter receiver offsets of 3-5 km far field condition does not apply for frequencies below 4kHz, which permits the use of standard MT inversion. Here we show first inversion results of these data using our new EM inversion routine taking the transmitter position into account. In addition to the active source MT data, we also collected conventional MT data on a larger scale crossing the Koillismaa intrusion. Our inversion routine also allows the inversion of MT data. We are thus showing first inversion results of joint inversion of both datasets. 

How to cite: Patzer, C., Xiao, L., and Kamm, J.: The first application of a new 3D octree finite element inversion framework to CS/MT data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15611, https://doi.org/10.5194/egusphere-egu24-15611, 2024.

In Italy, the MARGE initiative, an abbreviation for Geoelectromagnetic Risk Map for Central Italy, strives to create an extensive map of subsurface electrical conductivity by analyzing natural electric and magnetic fields.

Led by the National Institute of Geophysics and Volcanology in collaboration with the University of Bari and the Institute of Environmental Analysis Methodologies at CNR, his project involves establishing measurement points distributed on a grid spaced approximately 50 km apart.

However, this endeavor faces significant challenges in the central region of the Italian peninsula due to extensive urbanization, numerous electromagnetic disturbances from railways and high-voltage power lines, and challenging topography, making finding suitable land parcels a complex task.

The MARGE project aims to gather broad-band and long-term magnetotelluric data, focusing on two primary objectives: utilizing magnetotelluric data to outline large-scale lithospheric structures in the Central Apennines and developing maps of the geoelectric field in Central Italy to support Space Weather modeling and critical infrastructure vulnerability analysis.

Presenting our initial findings, we discuss encountered challenges and potential solutions identified in this ongoing project.

How to cite: Pignatiello, G., Coco, I., De Girolamo, M., Di Persio, M., Giannattasio, F., Materni, V., Miconi, L., Miconi, M., Piangiamore, G. L., Romano, G., Romano, V., Santarelli, L., Sapia, V., Spadoni, S., Tripaldi, S., Tozzi, R., Siniscalchi, A., and De Michelis, P.: Mapping Subsurface Conductivity: Challenges and Progress in Italy's MARGE Project, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18165, https://doi.org/10.5194/egusphere-egu24-18165, 2024.

The uranium deposits of the Athabasca basin (Canada) represent one of the world’s highest-grade uranium resources. They are unconformity-related type at the base of relatively flat-lying sequences, where faults acted as circulation paths for hydrothermal fluids. The fault zones often contain graphitic mineralization and hence represent a valuable exploration guide of small lateral extension but detectable by electromagnetic (EM) surveys. Time-domain EM (TEM) is the method of choice for uranium exploration in the Athabasca, and taking into account the frequencies involved we can approximate the graphitization along the fault as a conductive thin plate.

To better determine the geometry of the deposit, it might be crucial to recover the subsurface resistivity and the geometric parameters of the plate (position, dip, depth, azimuth etc.). Moreover, the assessment of the uncertainty associated to the parameters can help to evaluate the reliability of geological models and to guide the subsequent drilling activities.

A quantitative approach consists of employing Bayesian inversion algorithms, which allows to exploit the prior information available. Indeed, Bayesian inversion algorithms aim to solve the inverse problem statistically returning the posterior probability density function (ppdf). In particular, they are based on the Bayes theorem, which relates the prior information (e.g. from geological and petrophysical models) with the likelihood function to assess the posterior probability density function and thus the uncertainty. We implement the Differential Evolution Markov Chain algorithm (DEMC), a multi-chain approach that integrates the Metropolis selection rule with population evolution to sample the ppdf. The chains run in parallel and each current model is updated drawing two other chains and exploiting the models at the previous iteration. After an initial stage of burn-in, the algorithm reaches the stationary regime where the chains start sampling the ppdf resulting at the end in an ensemble of models. From these models the moments of first and second order (mean and variance) are computed obtaining the uncertainty of the inverse problem solution. As forward operator we employ the LEROI forward code developed by CSIRO (AMIRA), which computes the TEM response of one or more conductive 3D thin plates embedded in a horizontally layered earth.

In this work we propose the DEMC inversion of TEM data as a tool to assess thin plates parameters and uncertainty in the context of uranium exploration.

How to cite: Vinciguerra, A., Marquis, G., Girard, J.-F., Harrison, G., and Williard, E.: Uncertainty estimation of conductive thin plates parameters through a Bayesian approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19540, https://doi.org/10.5194/egusphere-egu24-19540, 2024.

Taking the sea area near the southern part of the Mariana Trench as a typical area is crucial for deep structural research in marine geology and geophysics. The magnetotelluric (MT) method has advantages such as large detection depth, sensitive to low resistance reactions, low cost, and high efficiency. The application of MT in deep water requires instruments with high reliability and stability, low noise, wideband, low power consumption, and miniaturization. The ocean bottom electromagnetic receiver (OBEM), as one of the important instruments for MT in deep water observation, its performance directly affects the quality of detected data.

In response to the shortcomings of the existing 6000 m level OBEM, there is an urgent need to develop a 9000 m level hadal OBEM. According to the requirements, we have focused on overcoming the challenges of weak E-field measurement technology, low-power and low-noise M-field measurement technology, low-power underwater acoustic release technology, and water surface large-scale recycling technology. We have achieved lower noise, longer underwater operation time, and efficient operations, providing reliable and stable instruments for hadal MT observation.

We have developed a chopper amplifier that matches deep water E-field sensors, analyzed the causes of injected charges, and adopted a scheme that combines peak filtering technology and dead zone technology to suppress residual misalignment generated during the chopper modulation, effectively reducing 1/f noise in the circuit, expanding the input range, and improving input impedance.

An orthogonal fundamental mode fluxgate based on digital demodulation is developed. Digital closed-loop real-time processes such as high-precision ADC, digital synchronous demodulation, digital integration, and high-precision large dynamic range DAC are used to reduce the switching charge noise introduced by analog circuits. Developing adaptive closed-loop feedback control algorithms to achieve fast feedback compensation with low noise and large dynamic range can help improve key parameters such as noise bandwidth, and input range of sensors.

We adopt a deep-water acoustic release system, pressure-resistant acoustic transducer, and control module prototype. Hydroacoustic communication controls the opening of the constant current source and the electrocorrosion decoupler. This solution reduces the size of the instrument and only relies on a single glass ball to achieve the floating of the instrument. The system integrates commands such as status query, electrocorrosion on and off. The status information includes distance, electrocorrosion status, battery voltage, etc. The propagation distance of acoustic signals is greatly increased, improving the success rate of underwater acoustic communication.

The glass ball is equipped with a beacon module, which is controlled by acoustic signals to activate the AIS, achieving real-time transmission of the OBEM position. Besides, high-power LED flashing is controlled to facilitate nighttime recycling and further reduce the cost of offshore operations.

In August 2023, 5000 m level test was conducted in the southern South China Sea. It is preliminarily verified the MT measurement, which has been improved in terms of low power consumption, low noise, and adaptability to deep sea. In the future, we will conduct test verification in deeper sea.

How to cite: Song, S., Deng, M., Sun, Z., Luo, X., and Chen, K.: Development of 9000 m level hadal OBEM, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20965, https://doi.org/10.5194/egusphere-egu24-20965, 2024.

At present, we are using commercial ground penetrating radar (GPR) to inspect tunnel walls, conduct an underground geological structure assessment and anticipate geology behind the tunnel face. A variety of metal objects, include portal frame, forklift, and excavator, can cause back reflection in the GPR profile during the test in the tunnel. Typically end users of GPR are unable to appropriately interpret the GPR profile because they are unware of what is actually coming from back reflection in the air and projection into the ground penetrating radar profile or from subsurface. They really need some method to identify real reflection signals from underground sources.

The GPR antenna transmits electromagnetic (EM) waves that can travel all space, including the air, the interface between the ground and the air, and the subsurface. During EM travel in the air, there is some back reflection from the air object to be recorded in the GPR profile during data collection in the field. We need to measure and recognize and elimate this back reflection interference noise. We have made electromagnetic waves absorbent block configuration for the GPR antenna that can complete cover the GPR antenna. We have done the comparative experiments tests with and without electromagnetic waves absorbent block have been conducted in the field, the results show that, without this block, GPR profile recorded many back reflection from the air objects, while the GPR antenna with covering electromagnetic waves absorbent block can only record the refection from surbsurface during data collection in the field, and it is clear GPR profile. This allows the GPR end user direct interpret the GPR profile only with reflection from surbsurface as it may completely eliminate back reflection from the air object.

How to cite: Deng, X.: A method to collect clear profile with Ground Penetrating Radar in tunnel, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21417, https://doi.org/10.5194/egusphere-egu24-21417, 2024.

In this study, we conducted an extensive geophysical survey to explore the potential of electrical resistivity methods in delineating deep ore deposits within between Koillismaa Intrusion and Näränkävaara intrusion, northeastern Finland. Preliminary investigations in 2022, including magnetic, gravity and audio-magnetotelluric (AMT) methods, along with drilling, uncovered significant anomalous structures in the survey area. Subsequent drilling of an exploration well provided positive lithological indications of a ultramafic igneous rock at more than 1.5 km depth, which are very likely of the same age as the layered intrusions in the area. Borehole data indeed revealed that the Archaean basement gneiss extends down to approximately 510 m, underlain by a granite dyke with interspersed thin layers of pyroxenite and peridotite. Notably, peridotite layers around 1500 m depth exhibited distinct magnetic and IP responses in core data.
We employed electrical methods at the site, including electrical resistivity tomography (ERT) and induced polarization (IP). To cover a large-scale area, 25 transmitter dipoles, each 1 km long and using three different transmitter systems, were deployed and data were recorded at 119 receiver stations. This work presents the acquisition and preliminary results from the ERT-IP surveys. During the processing of ERT and IP data, we utilized full time-series data recorded across the four lowest main frequencies (from 0.0625 Hz to 8Hz) to capture voltage data in a steady state. Apparent resistivity data were derived from the stacked voltage data, while IP data were initially extracted from these decay curves of these stacked voltage data and subsequently processed in the frequency domain (outphasing). Analysis of the resistivity and IP responses revealed notable IP signals at depths exceeding 1.5 km. Meanwhile, the resistivity data indicated generally very high values, around 10,000 ohm-m, with complex variations observed near the surface. This study demonstrates the efficacy of ERT and IP methods in delineating deep-seated mineral deposits, with the deep-depths IP responses being particularly noteworthy.

How to cite: Kim, B., Deparis, J., Darnet, M., Bretaudeau, F., Vedrine, S., Gance, J., Kamm, J., Autio, U., Patzer, C., and Heinonen, S.: Measuring Induced Polarization signals from deep seated magma chamber – preliminary results from a pilot survey in Finland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21924, https://doi.org/10.5194/egusphere-egu24-21924, 2024.

The Heath Discover – Advanced Mobile Leak Detection (AMLD) is an ultra-sensitive advanced technology capable of detecting natural gas leaks or emissions from a remote distance while driving on a street or right of way. It allows the user to cover large areas for compliance or emission surveys and provides reports and GIS data with breadcrumb trail on a Windows-based tablet app.

The Discover AMLD employs a mid-IR open path version of the proven TDLAS technology which has been used in other Heath Products such as RMLD-CS. It uses two Mid-Infrared Lasers, one each for Methane and Ethane, that pass through the air in front of the vehicle. As the lasers pass through a gas plume, the methane and ethane absorb a portion of the light, which the instrument detects. Based on the local meteorological conditions, a given amount of gas escaping from the ground will produce a plume that varies in size and uniformity of concentration levels. The plume, by nature is variable and dependent on the soil type, moisture, temperature, wind, venting and leak rate.

The Discover AMLD technology is already employed at 4 major gas utilities 2 domestic and 2 international and is being used to find real world leaks and disaster-based surveys. It is helping to distinguish between sewer/Biogas leak and pipeline leaks and is able to localize and quantify the methane emissions. The technology was demonstrated in real world conditions at more than 50 domestic and international gas utilities with excellent results. METEC facility at Colorado State University has done extensive testing and confirmed the efficacy and accuracy of the technology in its ability to find, localize & quantify emissions. This is helping utilities rapidly find leaks and reduce methane emissions to keep communities safe and reduce greenhouse gas emissions.

The technology was developed and commercialized by Heath Products division by connecting with research scientists at Physical Sciences Incorporation a premier research organization based in Massachusetts and utilizing their most innovative ideas and bring them to life. By using their TDLAS technology and adopting it to an open path vehicle mountable system that can be very versatile and completely wireless without the need to modify the vehicle, Heath engineers and technicians were able make it into a manufacturable product and make it available commercially in the last quarter of 2022. Since then, the product has been demonstrated and has impressed the technology evaluation laboratories of gas utilities and academia with its real-world prowess in rapidly discovering methane emissions and improving productivity of surveys by a multiplier of 4 or more. We believe that this will be a game changing technology that will help utilities in making their operations safer, build trust with communities and make environmentally friendly energy available to hundreds of millions of people.

How to cite: Wehnert, P. and Six, E.: Discover Advanced Mobile Leak Detection (AMLD) - Natural Gas Leak Surveys Utilitzing Mid-IR Open Path TDLAS , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1698, https://doi.org/10.5194/egusphere-egu24-1698, 2024.

The recent global focus on anthropogenic methane emissions mitigation has accelerated the development and deployment of novel technologies to detect, quantify, locate and prioritize mitigation of fugitive and process emissions of methane, particularly within the oil and gas supply chain. The majority of emissions within this infrastructure result from large and intermittent sources. One study¹ showed that the largest 5% of emissions (i.e. super emitters) typically contribute over 50% of the total emission volumeand another study² found that most sources (66%) are intermittent, and account for most (48%) of the emissions. The largest impact on emissions mitigation therefore can be realized by deploying detection methods and technologies that are matched to how these two classes of emissions manifest in the infrastructure. Continuous monitoring solutions that can image and pinpoint emission sources are especially well-suited for use at sites that are expected to have intermittent process emissions.

We present recent work utilizing novel Quantum Gas Lidar for continuous methane emissions monitoring in sludge treatment works where methane-rich biogas is produced from the anaerobic digestion of sewage sludge. Some of the biogas is consumed on site and the rest is cleaned, upgraded and fed into the natural gas distribution network. Monitoring campaigns are ongoing at three such plants in the UK, owned and operated by Severn Trent, two of which have full gas to grid infrastructure. The third site uses combined heat and power engines to convert the biogas into electricity for use on site. Specific elements of the infrastructure are targeted for continuous, automated measurement by the lidar system (especially the digesters, gas storage, combined heat and power engines and gas to grid plants) and any detected methane emission plumes are imaged, their origins are pinpointed, and their emission rates are quantified. This results in a methane emission rate dataset having both high spatial and temporal resolution which can be used for both component and site-level emissions reporting within, for example, the OGMP 2.0 level 4 and level 5 framework, and IPCC Tier 3 (facility level) reporting. ³ The individual emission sources are intermittent and can have emission rates that vary in time depending on various process variables (i.e. varying pressures within the equipment) so that an accurate accounting of the overall emissions over time is reliant on the high-accuracy quantification and high temporal resolution that the lidar system provides. The continuous measurements have so far identified some previously unknown emission sources and have allowed the actual emissions of those sources to be accurately quantified for the first time, offering a high-confidence, measurement-based accounting of the methane emissions at these sites.

How to cite: Van Pelt, A., Srinamasivayam, B., Harrison, A., Millington-Smith, D., and Lindsay, G.: Using Quantum Gas Lidar for Continuous Methane Emissions Quantification of Gas to Grid Plants in Water Sewage Treatment Works., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2391, https://doi.org/10.5194/egusphere-egu24-2391, 2024.

To develop methods based on integrating the two-phase (liquid and gas) flow and free flow in the porous media to optimize the operation of subsurface gas venting, we developed a two-dimension soil aeration model based on the coupling of two-phase flow (liquid and gas) in the porous media with the single-phase flow (methane, CH₄) in the free-flow domain under homogeneous, isotropic, and isothermal conditions. The dissolution, bioreaction, and thermal diffusion of CH₄ are not included in the model. Numerical experiments were conducted with diverse near-surface meteorological conditions, soil properties (e.g., porosity, soil layering, air permeability, and soil moisture), and the deployment of venting bar holes to study the effects of environmental conditions and venting system designs on the gas flow in the subsurface. Simulation results not only demonstrated the capability of the soil aeration model on the prediction of the migration of the residual CH₄ concentration in the subsurface due to the venting but also highlighted the influence of soil permeability, deployment of venting bar holes, and the venting pressure on the change in residual gas concentration in the unsaturated zone. During the soil aeration, the low soil permeability impacted the migration of advective air flow by venting in the soil and prolonged the operation time of the soil aeration. Furthermore, the Peclet number of the gas migration significantly decreased from the center of the venting bar hole with the decrease in soil permeability and venting pressure. The variation of venting pressure is more sensitive to the development of venting flow rates than that of the number of venting bar holes. The proposed 2D soil aeration model and approaches of evaluation of soil aeration in this study provide insights to investigate the multiphase flow in the subsurface due to soil aeration operation under various environmental conditions and venting strategies.

How to cite: Lo, J.-H., Smits, K., and Zimmerle, D.: A Two-dimensional Model for the Gas Transport in the Unsaturated Zone with the Soil Aeration, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4195, https://doi.org/10.5194/egusphere-egu24-4195, 2024.

Natural gas (NG) leakage from belowground pipelines is currently poorly understood, even though it is an area of safety, environmental, and economic concern. To date, there are limited studies on the transient behavior of NG, defined as the speed and maximum extent that gas travels belowground, and how this behavior changes with soil, environmental and leak characteristics. What is least identified is the interrelation between each controlling parameter, how to properly parameterize and characterize as well as the proper field application, specifically operator and first responder protocols. To address this gap, this work identifies key parameters influencing the transient behavior of leaked NG in the subsurface and opportunities to link this understanding to operator practice.  Though a three-year long series of over 150 controlled release experiments conducted at Colorado State University’s Methane Emission Technology Evaluation Center (METEC) and parallel numerical modeling we’ve investigated subsurface methane migration rates and extents and subsequent emission to the atmosphere. Experimental results were used to understand overall transient behavior both during and after terminating the leak. Numerical simulations were then used to extend experimental results to other conditions (e.g. additional soil types, surface conditions, and belowground infrastructure). Results demonstrate the impact of temporary rain and snow surface conditions on the extent and duration of leak transport, resulting in levels that pose heightened environmental and safety risks.  Furthermore, after leak termination, our findings demonstrate the isolated changes in the belowground migration time and the extent of leaked gas, driven by changes in surface and atmospheric conditions, a key point not consistently included in risk assessments or environmental emission rate calculations. While efforts to study a wider range of environmental conditions is underway, the findings of this study provide crucial insight to on identifying and prioritizing emissions from the perspective of both safety and the environment. 

How to cite: Smits, K., Jayarathne, N., Zimmerle, D., Riddick, S., and Kolodziej, R.: Unraveling Natural Gas Migration Rate and Extent from Leaking Underground Pipelines under Varying Environmental Conditions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4598, https://doi.org/10.5194/egusphere-egu24-4598, 2024.

Periodic comprehensive or screening leak detection and repair (LDAR) surveys are a central part of many current regulations, which are intended to reduce unintentional methane emissions caused by leaking infrastructure.  In principle, by swiftly identifying and repairing leaks, emissions of methane, a potent greenhouse gas, are reduced.  The primary tools used for comprehensive LDAR surveys are Optical Gas Imaging (OGI) cameras.  While OGI can be effective for detecting and visualizing methane leaks, its extension to quantitative measurement (QOGI) is notoriously imprecise.  Moreover, studies have shown considerable variation in the performance of OGI in practice, where successful use is heavily dependent on the skill of the operator. 

Manual OGI surveys are also time consuming and labour intensive.  Implementing and maintaining an effective LDAR program that involves multiple OGI surveys per facility can be costly, potentially disrupting routine operations while requiring the deployment of trained personnel to each site.  Although operators are obligated to address and verify the repair of identified leaks, there is also still potential that significant leaks may be allowed to persist if they are not initially detected.  Consequently, despite the substantial costs involved, the full potential of methane reduction benefits may not be realized.  By contrast, aerial surveys have the potential to overcome many of the negatives associated with OGI surveys. In particular, aerial surveys can permit large numbers of sites to be surveyed per day at significantly lower cost per site, reducing overall compliance costs, labour requirements, and improving safety through reduced risks.  However, there remains no objective way to assess the relative performance of aerial surveys in complementing or replacing LDAR surveys under different scenarios.  In the context of emerging regulations, this is an especially important topic.

This work seeks to directly compare the effectiveness of conventional OGI surveys and aerial measurement under real-world conditions.  At an identical set of approximately 500 operating oil and gas sites in British Columbia, Canada, we compare and contrast detected and quantified sources in regulated LDAR surveys with parallel aerial surveys completed using Bridger Photonics’ Gas Mapping LiDAR (GML) technology.  The publicly reported LDAR reports are parsed to analyze patterns in detected emissions on 1 and 3 times per year deployments which are contrasted with aerial measurements at the same set of sites.  This direct contrast under real world conditions gives one of the first large scale tests of LDAR and aerial performance in practice, helping to provide quantitative guidance for the design of potential alternative LDAR programs under emerging regulatory scenarios.

How to cite: Wilde, S., Tyner, D., Conrad, B., and Johnson, M.: A Comparison of the Effectiveness of Regulated OGI Leak Detection and Repair (LDAR) Surveys and Aerial Measurements in the Real-World, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6658, https://doi.org/10.5194/egusphere-egu24-6658, 2024.

Establishing a streamlined workflow within the Monitoring, Measuring, Reporting, and Verifying (MMRV) framework is crucial for effective methane emission management and accurate methane emission reconciliation in the oil and gas (O&G) industry. Despite existing MMRV standards such as the Oil & Gas Methane Partnership 2.0 (OGMP 2.0), Veritas 2.0, and MIQ providing valuable guidance, the O&G industry still faces obstacles in compliance with these standards. These obstacles include (1) The Bottom-Up (BU) inventory, constructed with generic activity and emission factors, underestimates emissions and poses gaps in closing uncertainties during the reconciliation process, (2) The decision to deploy one or multiple methane sensing technologies, relying on emission profiles derived from limited sample measurements, can not accurately represent all emissions due to their inherent limitations and the stochasticity and intermittency of emissions, (3) No standard has been employed to assimilate observations from sensing technologies with varying measurement scales and data from operational events, and (4) Addressing various uncertainties, including those arising from direct measurements, atmospheric inversion modeling, and population inference from sample emission events, proves challenging in the final stages of the reconciliation process.

In this study, we present a streamlined MMRV-focused workflow integrating established and novel methodologies for reconciling emissions. The workflow consists of five key steps: Firstly, using the Oil and Gas Production Greenhouse Gas Emissions Estimator (OPGEE) to construct more accurate BU inventories and emission profiles for each type of equipment; secondly, determining the technology deployment plan and work practice based on constructed emission profiles using the Leak Detection and Repair Simulator (LDAR-Sim); thirdly, assimilating real measurements from deployed technologies through an ISO/OGC standard-based integrated sensor web architecture; fourthly, leveraging assimilated measurements and operational data to resolve emission events and reconcile the emissions; and finally estimating uncertainties from emission quantifications, inaccuracies in establishing emission event duration, and missed emission events. We demonstrate this workflow using data from the upstream O&G sites provided by an anonymous company. At the end of the demonstration we reconcile and report emissions by following the OGMP 2.0 guidelines. 

How to cite: Gao, M. and Liang, S.: Toward developing a streamlined workflow for methane emission monitoring, reporting, and verification in the oil and gas industry, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7156, https://doi.org/10.5194/egusphere-egu24-7156, 2024.

The goal of reducing anthropogenic methane emissions, in particular those arising from oil and gas operations, will require the implementation of routine and effective monitoring, both to detect repairable emissions and to reliably report emitted quantities. This will mean a transition from research investigations to more formal requirements for monitoring which will be the responsibility of industry. Methane emissions are particularly challenging to measure as the sources are highly inhomogeneous in terms of the ranges of their emission characteristics such as emission rate, temporal behaviour, and the wide variety of potential sources of emissions (ducted emissions, vents, fugitive leaks from components, storage tanks, flares, onshore and offshore facilities). To enable baselining and reliable reporting from across different parts of the oil and gas industry, and to address the different needs from detection to quantification, a range of different methods based on different measurement technologies are needed. This has resulted in a large number of available and developing approaches. Industry will need confidence in the emissions data they report as they will be used to guide emission reduction activities and to report into international frameworks such as the IMEO. In future there will be increasing regulatory pressure.   
To support these growing requirements, and to support the selection of appropriate methods, there is therefore a need for a metrology framework to ensure the quality, reliability, comparability and suitability of measurement methods. It is important that the measurement uncertainties associated with methods are well understood including key sources of uncertainties, and the impact of the use of methods in different conditions and locations. This will not only support the selection of appropriate methods, but also enable the interpretation and comparison of data between sources and over different scales (both temporal and spatial).
This talk will outline these issues, review the requirements for defining clear measurement objectives and performance requirements and provide an illustration of what such a metrology quality framework would look like.  The talk will discuss the issues around determining the uncertainties in methane emission measurements and in particular in derived data such as emission rates, and the use of validation studies and controlled releases will be discussed. It will also provide an overview of current activities to develop standardised methods for monitoring methane emissions and to develop the tools to support the evaluation of such methods.

How to cite: Robinson, R., Innocenti, F., and Helmore, J.: The requirements for standardisation and performance evaluation for methane emissions monitoring technologies – a metrology perspective., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10605, https://doi.org/10.5194/egusphere-egu24-10605, 2024.

We present an overview of aerial Gas Mapping LiDAR (GML) technology and its application to methane emissions monitoring and informatics for oil and gas infrastructure. The GML sensor combines spatially scanned and coaligned topographic and path-integrated methane concentration LiDAR measurements with navigation data and aerial photography to provide episodic detection, localization, emission rate quantification, and emission source attribution of methane plumes within scanned infrastructure. Aerial deployment enables rapid and efficient coverage of large and dispersed infrastructure. High sensitivity LiDAR measurements allow detection of methane emissions at rates below 1.5 kg/h with greater than 90% probability of detection in most deployment conditions, resulting in the detection of more than 90% of emissions from typical oil and gas production basins. The high spatial resolution of the LiDAR scans provides geo-location of emission sources, typically to within 2 m, for targeted LDAR response and reliable emission source attribution. Well characterized emission rate estimates, produced by combining LiDAR methane concentration measurements with gas flow speed information, allow source-level prioritization of LDAR response and enable accurate source-resolved methane emissions inventories.  Real-world examples of Gas Mapping LiDAR use cases will be presented and requirements for producing large-scale methane emission inventories including sample planning, facility and equipment identification, emission rate quantification accuracy, detection sensitivity, and statistical analysis methods will be covered. Specific applications of the GML technology include leak detection and repair (LDAR); measurement, monitoring, reporting, and verification (MMRV) programs; measurement-based methane emissions inventory and intensity benchmarking and reductions tracking; and differentiated gas certification programs. © 2024 The Author(s)

How to cite: Thorpe, M., Kreitinger, A., Roos, P., Brasseur, J., Losby, B., Greenfield, N., Carre-Burritt, A., Kunkel, W., Altamura, D., Dudiak, C., Donahue, C., and Moscona, B.: Aerial Gas Mapping LiDAR for Methane Emissions Management at Oil and Gas Infrastructure, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13335, https://doi.org/10.5194/egusphere-egu24-13335, 2024.

This work will present a quantitative evaluation of the potential for measuring gas flare combustion efficiency using an aspirating sensor platform mounted under an uncrewed aerial vehicle (UAV).  The UAV sensor package contains lightweight commercial gas analyzers capable of precise measurements of atmospheric methane (CH₄), ethane (C₂H₆), carbon dioxide (CO₂), and carbon monoxide (CO).  By sampling the flare’s plume of combustion products with the help of a UAV, flare efficiency measurements can be safely and remotely completed without affecting the flare’s operation.  The relative mole fraction of the measured major carbon containing species can be used to close a carbon mass balance, which permits calculation of a local carbon conversion efficiency of the flare.  However, because the composition of the flare plume can be inhomogeneous as well as turbulent, it is not straightforward to determine whether the measured incomplete combustion products are representative of total inefficiencies.  Further uncertainty arises if the flared gas contains additional hydrocarbon species (e.g., C3+ hydrocarbons) that may not be directly measurable by the UAV platform.  To address these challenges, controlled experiments were completed on large scale (100-mm diameter) flares burning within Western University’s Boundary Layer Wind Tunnel.  With the wind tunnel running in an open circuit configuration, the UAV/sensor package was suspended within the wind tunnel test section downstream of the flare where it measured combustion efficiency while being moved in and out of the combustion plume.  Results were compared with known combustion efficiencies for identical operating conditions obtained following the established method of Burtt et al. (J. Energy Inst. 2022).  Further, combustion efficiency measurements from operating flares will be made using the developed sensor to validate the proposed measurement approach.  Ultimately, this tool could close a known gap in our ability to quantify carbon conversion efficiency and methane slip from flares under field conditions as required under emerging measurement, reporting, and verification (MRV) programs.  

How to cite: Festa-Bianchet, S., Mohammadi, M., Tanner, A., Kopp, G., and Johnson, M.: Evaluation of a UAV-Based Methodology for Measuring Flare Combustion Efficiency, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14031, https://doi.org/10.5194/egusphere-egu24-14031, 2024.

Recent emphasis on decreasing methane emissions from oil and gas production and transport has stimulated the development of multiple regulatory and voluntary reporting programs.  These programs include monitoring and verification requirements, commonly known as MMRV (methane monitoring, reporting and verification).  An underlying assumption in these programs is the use of advanced methods to estimate emissions, including continuously installed sensors at facilities and aerial, satellite and driving survey methods. These methods provide emission estimates at the scale of major sources or entire facilities. Regulatory programs in the USA and EU are increasingly tying these estimates to substantial financial risks while encouraging anonymous 3^rd party measurements, raising the stakes for using these methods.  This abstract reviews recent studies of these methods, and reviews four areas of concern. 

First, multiple commonly used methods display accuracy problems which are likely to be present in most methods. Recent studies study assessed methods at production and midstream facilities onshore in the USA.  Two methods deployed simultaneously at 14 midstream facilities disagreed by 2:1 averaged across all facilities and by more than 2:1 at 6 of the facilities.  Other studies in U.S.A production and European midstream have identified similar accuracy issues. 

Second, ‘measurement informed inventory’ methods, which use full-facility estimates to update emissions reporting, remain poorly developed and unevenly implemented.  While one study found that survey methods identified large emitters and operators corrected reporting, another study found that most aerial detections did not result in effective corrections to inventory estimates. 

Third, methods used to extrapolate facility-scale estimates to basin scale have unaddressed uncertainties.  Recent work indicates that 9-49% of plumes detected by aircraft methods are due to maintenance emissions, which are poorly characterized by anonymous aerial sampling.  Additionally, extrapolation methods poorly estimate short emission events, resulting in a significant potential to over-estimate of emissions.  Conversely, random non-detects of exhaust emissions likely under-estimates emissions from engines and combustors by a factor of 2 or more.  These errors both shift emission between sectors and may result in significant bias. Additional control inputs, better GIS data, and improved methods are required to better estimate regional emissions.  

Finally, recent studies of continuous emissions monitors in both controlled and field tests indicate poor quantification accuracy in controlled testing, and poorer accuracy in field conditions. 

While advanced methods show promise for improving emissions detection and mitigation, consumers of these data need to be aware of the performance of these methods and account for bias, uncertainty, and variability of emissions estimates when constructing programs that utilize these estimates.

How to cite: Zimmerle, D.: Impact of Emissions Estimation Uncertainty on Methane Monitoring Reporting and Verification (MMRV) Programs, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14035, https://doi.org/10.5194/egusphere-egu24-14035, 2024.

Satellite observations are an important tool in large emission event detection and global monitoring of methane emissions from oil and gas facilities, but current satellite-based methods face significant uncertainty. One of the major sources of uncertainty is a high rate of false positives. Current methods to mitigate false positive rates typically involve manual inspection of plume imagery, a time-consuming process which introduces human error. The Sentinel-2 multispectral satellite is widely used in global methane observation, as methane enhancements can be identified by a signal in shortwave infrared bands 11 and 12.  However, physical, biological and other anthropogenic processes can have a similar spectral signature, leading to a high rate of false positives. We present an empirical False Discovery Rate approach for quantifying the false positive probability for a given candidate plume. Imagery data is divided into a near-to-well set (within 200m of oil and gas infrastructure) and a far-from-well control set (between 400m-1200m away from oil and gas infrastructure), which is conservatively assumed to consist entirely of false positives. With these datasets, we define the probability of a false positive given proximity to oil and gas infrastructure as a function of plume quality and distance to infrastructure.  The results from this approach are shown for a case study over the contiguous United States, where we found a strong relationship between the selected plume quality metrics, distance to infrastructure and the false positive probability. We also identified significant differences in plume characteristics between the near-to-well and far-from-well datasets.  This work presents a more efficient and data-driven false positive algorithm, which can significantly reduce the manual step in false positive identification, resulting in larger scale deployment and data processing of satellite-based methane emission monitoring.

How to cite: Rischard, M., Schissel, C., and Niazi, M.: Methane leak or false positive? An automated probabilistic treatment of detected emissions from oil and gas facilities in multi-spectral satellite imagery at continental scale., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16519, https://doi.org/10.5194/egusphere-egu24-16519, 2024.

Ambition on methane emissions reduction is growing, and open, reliable, measurement-based and actionable data is essential to track changes in emissions over time. The ability of countries and companies to meet their goals requires a thorough understanding of the magnitude and location of methane emissions, as well as being able to demonstrate progress towards these goals.  

As a core implementing partner of the Global Methane Pledge, the UN Environment Programme’s International Methane Emissions Observatory (IMEO) has been tasked with creating a sound scientific basis for methane emissions estimates and is providing reliable, public, policy-relevant data to facilitate actions to reduce methane emissions. IMEO is collecting and integrating diverse methane emissions data streams, including satellite remote sensing data, science studies, national inventories, and measurement-based industry reporting to establish a global, centralized public record of empirically verified methane emissions. 

Here, we will show the progress of IMEO towards developing its global, public dataset of policy-relevant methane data, highlighting successful mitigation case studies for the oil and gas industry from the pilot phase of IMEO’s Methane Alert and Response System (MARS), and from IMEO’s Methane Science Studies. We demonstrate how empirical data can drive real, tangible mitigation action in countries around the world.  

How to cite: Zavala-Araiza, D., Hamburg, S. P., Calcan, A., Schwietzke, S., France, J. L., Randles, C., Baranski, M. R., Demeter, M., Kupers, R., Field, R., and Caltagirone, M.: Transparent Horizons: IMEO's Methane Data Empowering Global Climate Action , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20055, https://doi.org/10.5194/egusphere-egu24-20055, 2024.

Curbing methane emissions is a crucial aspect of achieving emissions reduction targets across the world. This is particularly important in Colombia, where it is estimated that 24% of anthropogenic methane emissions originate from the energy sector (IEA, 2023). However, the mitigation potential remains hampered by a lack of understanding of emission sources in the field and limited access to accurate official inventories.  The objective of this study is to develop a comprehensive inventory of methane emissions within the oil and gas industry in Colombia. The implemented framework consists of a hybrid inventory that integrates top-down, source-resolved aerial measurements with bottom-up measurements following the published methodology of Johnson et al., Comms. Earth & Environ, 2023. This approach not only facilitates a detailed attribution of emission sources but also quantifies the measurement and sample size uncertainties, employing the detection probability of the airborne sensor, Monte Carlo analysis, and bootstrap analysis.  For this study, around 3,400 facilities were included in the top-down campaign, complemented by a select sample of facilities in a parallel bottom-up campaign. The total facility sample covers six different production regions across five departments, including a wide range of oil and gas facilities and production types. This presentation will discuss the initial results of the field campaigns and progress towards the completion of a first-ever measurement-based methane inventory for Colombia that is intended to be used to support verified reporting under the International Oil and Gas Methane Partnership (OGMP 2.0).

How to cite: Calderon-Cangrejo, N., Festa-Bianchet, S. A., Conrad, B. M., Tyner, D. R., Wilde, S. E., and Johnson, M. R.: Combining Aerial and Ground Surveys to Quantify Oil and Gas Sector Methane Emissions in Colombia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20581, https://doi.org/10.5194/egusphere-egu24-20581, 2024.

Hundreds of thousands of unconventional natural gas wells recently constructed across North America have transformed the global energy landscape and generated widespread concern relating to fugitive methane leakage. To date, no studies have evaluated the integrity of unconventional wells post-abandonment. Here, we evaluated emissions at nine decommissioned unconventional wells within the Montney region of British Columbia, Canada and found two exhibited co-emission of CH₄ and CO₂ from surrounding soils indicating integrity failure, releasing up to ~2000 kg of CO₂-eq/yr into the atmosphere. A further three wells exhibited statistically significant anomalous CO₂ fluxes of ~500 kg/year from surficial soils around the well, likely associated with minor integrity failure and derived from near total soil-based aerobic oxidation of fugitive CH₄. These findings suggest that more than half of decommissioned unconventional wells may generate emissions, however only relatively small contributions to GHG emissions result that are significantly mitigated through natural soils-based CH₄ oxidation.

How to cite: Cahill, A.: Evaluating Methane Emissions From Decommissioned Unconventional Petroleum Wells in British Columbia, Canada, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22532, https://doi.org/10.5194/egusphere-egu24-22532, 2024.

Climate change impacts are increasingly felt, and a key hazard for human health is exposure to chronic and acute heat. Air conditioning is an effective indoor adaptation technology. However, it is widely regarded as a form of “maladaptation” due to its high energy intensity and the detrimental impact it has on urban outdoor temperatures and global greenhouse gas emissions. On the other hand, urban green space (UGS) is widely regarded as an effective green infrastructure with potential to mitigate the urban heat island effect. In this context, here we built on a global validated model based on street-level vegetation density, satellite imagery, and ancillary covariates to track UGS in a large sample of cities worldwide (Falchetta and Hammad, forthcoming) and derive a context-aware but generalized statistical linkage with buildings electricity consumption statistics. Based on the modelled relations, we derive future projection of the potential contribution of UGS expansions to energy demand reduction in buildings in different regions of the world. Our study advances the quantitative, globally relevant understanding of the intersection between climate change adaptation and mitigation, and the role of nature-based solutions to reduce the feedback impacts of adaptation while providing ecosystem service co-benefits.

How to cite: Falchetta, G. and De Cian, E.: Urban green space: global assessment of potential energy demand reduction in buildings, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1444, https://doi.org/10.5194/egusphere-egu24-1444, 2024.

Vertical greenery (VG) reduces the indoor heat hazard. To take advantage of their cooling effects, the underlying key design factors have to be understood. However, the influence of plant species, building type, and VG design on the thermal advantages has received limited attention in current literature.
Therefore, heat fluxes and temperature profiles for different ground based VG designs in the temperate climate of Berlin, Germany, were analysed using a process-based model. Indoor temperature profiles were integrated, assuming that air conditioning (AC) had been installed. Cooling effects have been simulated for six parameterised plant species of varying ages, across three different building types, and alternated air gap and crop thickness.
The results were compared, quantifying the cooling potential and the possible energy savings. They differ between plant species and building types. The diurnal variation of the indoor temperature resulted in maximum savings during the night. Fallopia baldschuanica showed the highest energy savings of approximately 23%. Thereby, it was multiple times more energy efficient than a Humulus lupulus.
This illustrates the significance of selecting the appropriate VG plant species. Considering factors such as growth rates and potential harm to buildings, VG can be strategically optimzed.

How to cite: Dahm, Y., Hoffmann, K., Schinke, O., and Nehls, T.: Simulating the impact of ground-based façade greenery design on indoor heat stress reduction, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6337, https://doi.org/10.5194/egusphere-egu24-6337, 2024.

As the impacts of climate change intensify, bringing an increase in the frequency and magnitude of heat waves, the interest around urban heat mitigation strategies is rapidly growing worldwide. Green roofs, defined as roofing systems that incorporate a vegetated layer, have been proved to reduce urban heat, thanks to their evaporative cooling and lower heat storage than conventional roofs. Thus, they are expected to become increasingly important in the future, given their potential to counteract the projected temperature increases associated with climate change.

Numerous studies emphasize the urban heat mitigation potential of green roofs, yet accurate quantifications of their temperature reductions under future climate are currently lacking. For instance, under climate change, higher temperatures and longer dry periods are expected in central Europe, conditions that can negatively affect green roofs. Recently, microclimate models are gaining traction in evaluating the efficacy of heat mitigation strategies, facilitating the quantification of urban heat reductions under various climate conditions. However, despite their increasing use in the literature, microclimate models are rarely combined with climate projections, due to the complexity of downscaling interdependent weather variables such as precipitation, air temperature and global horizontal radiation. Consequently, the heat reduction potential of green roofs under future climates is largely unexplored, particularly in comparison to their observed performance under current climate. Additionally, it is unknown whether specific roof parameters could contribute to further enhancing heat mitigation, such as plant characteristics, irrigation schemes, or substrate depth.

This study aims to investigate the heat mitigation potential under climate change on a green roof in Mendrisio, Switzerland (characterized by hot, dry summers) using an open source microclimate model developed by Meili et al. (2020), Urban Tethys-Chloris (UT&C). This model was selected because of the fully coupled energy and water balance, and the incorporation of plant-specific characteristics. Continuous year-long monitoring of the green roof enabled to collect surface temperature using infrared sensors. These measurements were used to calibrate and validate the microclimate model. To account for climate change, coupled, sub-hourly, future projections of precipitation, air temperature, solar radiation, relative humidity, and wind speed were used as input to the validated microclimate model. These projections were derived from a convection resolving climate model (COSMO forced by MPI-M-MPI-ESM-LR at RCP 8.5, worst-case emissions scenario) run over the European domain at a 2.2-km, 6-minute resolution for a 10-year period that was bias corrected through quantile mapping. Lastly, variations in key parameters like substrate depth, vegetation type, and green roof irrigation schemes were explored to analyze their impact on urban heat mitigation under climate change.

Preliminary, manual calibration of the microclimate model resulted in a good predictive ability (r² = 0.71), which will be further improved with automatic calibration. In a current climate, the green roof was able to reduce maximum surface temperatures in Summer by approximately 15°C, with respect to an adjacent concrete roof. Further expected results will evaluate potential temperatures reductions in a future climate and determine whether green roofs can counteract increasing temperatures by exploring a range of alternative designs.

How to cite: Cavadini, G. B. and Cook, L.: Evaluating Green Roof Heat Mitigation Potential in a Changing Climate, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7729, https://doi.org/10.5194/egusphere-egu24-7729, 2024.

Rainwater harvesting for indoor uses could be a useful practice for a sustainable management of urban water. The realization of a rainwater harvesting system strictly depends on the costs and the required space so that an accurate design is necessary, especially in the tank sizing step. The volume of the tank is an important element of the system which impacts not only important environmental issues such as the volumes of saved potable water and the reduction of rainwater volumes to the sewerage system, but also the costs and the practical realization of the rainwater harvesting system. Nevertheless, while the professional world seeks solutions that are easy to apply (e.g. simplified sizing methods), from a scientific point of view several aspects are still to be clarified, among these the role of the temporal variability of rainfall in the tank sizing step, that is the object of the present study.

Rainfall temporal variability is quantified by the Coefficient of Variation (CV) of rainfall datasets. This analysis is carried out through numerical simulations and it is focused on the national Italian territory. Daily rainfall data of 3436 rainfall gauge stations located on the national Italian territory are considered and buildings with different catchment area and number of persons are taken into account. Our computations show that the majority of rainfall gauges in Italy has a rainfall CV in the 2.5-3.5 range, with higher values in the South and in the main islands. The role of the temporal variability of rainfall is clear: the same building in locations with the same mean annual rainfall depth, can require different tank sizes according to the rainfall coefficient of variation of the specific location. As an example, to reach the same water saving, a medium rise building located in Ascoli Satriano (CV=2.42) should be equipped with a tank size of 2700 litres, while in other locations which have the same mean annual rainfall depth but different CV, like Casale Monferrato (CV=3.41) and Muravera (CV=4.83), the required capacity is 3400 litres and 6800 litres, respectively. This underline the importance of taking into account the rainfall temporal variability in the tank sizing.

The analysis made use of non dimensional parameters, i.e. the storage fraction and the demand fraction, so that the results, obtained from different buildings over the Italian territory, are comparable, allowing in this way to build a unique graph that contains all information: the water demand, the mean annual rainfall depth and the rainfall coefficient of variation, as well as the number of inhabitants and the roof area of the building.

How to cite: Carollo, M. and Butera, I.: Rainfall temporal variability and rainwater harvesting efficiency: an analysis over the Italian territory. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12889, https://doi.org/10.5194/egusphere-egu24-12889, 2024.

Green walls, facade greenery, living walls – vertical building greening as part of urban green infrastructure are measures for climate sensitive urban design, for water management and microclimate regulation. Strategic integration of green walls into local water and energy cycles requires prediction of evapotranspiration, considering the individual design, plant species, and building characteristics. Available models address horizontal surfaces but disregard vertical particularities and urban conditions, e.g., reduced direct radiation, spatial patterns of radiation on the wall due to building orientation and shading obstacles, and very heterogeneous wind fields that are influenced by rough surfaces, canyons, and adjacent wind barriers. We present a verticalization model, ET₀^vert, for the reference crop evapotranspiration ET₀ (FAO) based on a sensitivity analysis. It comprises the adaptation of solar radiation and wind to the individual situations in front of a wall or facade. The accuracies of the model predictions are evaluated for (i) remote climate station data (horizontal reference plane), (ii) interpolated climate data (both horizontal and vertical reference plane) and (iii) on-site measured climate data (vertical reference plane, both not height-adapted and height-adapted) as input. We validate the model with data for a one-month reference period (25/07/2014 – 29/08/2014) from a weighable lysimeter with Fallopia baldschuanica greening of a 12 m high wall in Berlin, Germany.

Regarding individual meteorological input parameters, we found high relevance of both vapor pressure deficit (VPD) and solar radiation (R_S) for the study area. Using VPD and R_S, respectively, a linear model could explain 90 % and 85 % of daily ET₀ variances. No such relationship could be detected for wind speed, but for maximum and minimum wind speed.

Compared to remote horizontal input data, verticalization of input data (R_S and wind) reduced overestimations of ET from about 90 % to 14 % and 27 % for the daily and hourly resolution, respectively. If onsite climate data is available, deviations are reduced to 9 % and 5 % for the daily and hourly resolution. Height-adaptation of input data resulted in further improvements of the prediction accuracies (1 % and 2 % deviation for hourly and daily resolution).

We conclude that simply using remote horizontal climate data for calculating ET of green walls is not advisable. Instead, any input data, onsite measured or remote climate station data, should be verticalized and preferably height-adapted. The verticalized model predicts the hourly and daily evapotranspiration of green walls necessary for e.g., irrigation planning, building energy simulations or local climate modeling.

For more information: https://doi.org/10.5194/hess-2023-22

How to cite: Hoffmann, K. A., Saad, R., Kluge, B., and Nehls, T.: Modelling reference evapotranspiration of green walls (ET0vert), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15912, https://doi.org/10.5194/egusphere-egu24-15912, 2024.

Urbanization and climate change are leading to an increase in urban heat, posing a threat to human health and well-being. Urban green spaces (UGS), such as parks and gardens, have been recognized as an effective strategy for heat mitigation because they dissipate heat within their boundaries and in the surrounding areas. The magnitude of the cooling effect of UGS varies across locations and is affected by various factors, such as background climate, urban fabric, and vegetation properties. However, previous research studying the effect of UGS typically focused on specific case study areas and particular aspects of driving factors.

To do so, we integrate modeling, remote sensing datasets, and on-site measurements to assess the microclimate conditions of five different UGS (allotment gardens, public parks, private gardens, real estate yards, and ruderal sites.) in three Swiss cities with different biophysical conditions (Zurich, Geneva, and Lugano). Urban Tethys-Chloris (UT&C) model, a novel urban ecohydrological model with an explicit representation of urban canyon and vegetation properties, is applied to simulate the microclimate for each UGS and city. The models are validated using on-site measurements for air temperature, relative humidity, and surface temperature from July to October 2023. Preliminary results for Zurich show a good fit between simulation results and on-site measurements for both three variables, especially for air temperature and surface temperature with both R-squares larger than 0.8.

During the simulation period from June 21 to October 3, results will identify diurnal and daily patterns of microclimate conditions, including how different vegetation properties (i.e., height, canopy width, leaf area index, stomatal conductance) affect the microclimate. Subsequently, statistical regression will be employed to explore how the cooling effect of UGS is related to the distinct urban fabric and background conditions. Overall, the study will explain how various factors influence urban microclimate and provide insights on which factors will help to enhance the cooling effect in urban green space design.

How to cite: Yin, Y., Manoli, G., and Cook, L.: Assessing the microclimate conditions in urban green spaces and the effects of underlying driving factors in Switzerland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16430, https://doi.org/10.5194/egusphere-egu24-16430, 2024.

Water consumption is a fundamental global need.  Water production consumes lots of energy and emits plenty of greenhouse gases.  Determining the carbon footprint of water can offer various benefits. Reducing water use and conserving water can lead to lower energy consumption, lower carbon emissions, lower monthly water and energy costs, and less demand for water.  As carbon neutrality gradually prevails, low carbon emissions have become the future global trend and goal.  Therefore, it is crucial to understand the relationship between water consumption and carbon emissions.

As most countries struggle to reduce their carbon emissions in response to global warming, investments in water conservation, efficiency, and reuse are among the most cost-effective energy and carbon reduction strategies.  Urban water infrastructures have been demonstrated to contribute to global CO2 emissions significantly, and buildings account for a large portion of most urban water consumption.  Notably, while there is abundant rainfall in Taiwan, there appears to be a frequent water shortage crisis.  Such a crisis is aggravated by climate change because of the more unpredictable seasonal changes.  Climate change is linked to excessive anthropogenic carbon emissions. 

This study focuses on five types of buildings with various missions and usage on the National Taiwan University campus.  These infrastructures are typically deemed as having significant water consumption at National Taiwan University: (1) Residential buildings, (2) Experimental buildings, (3) Experimental farms, (4) the Department of Animal Science and (5) Lecture halls.  The specific objectives of this project are to uncover the nexus between thermal comfort and water consumption and the relationship between water consumption and hydro-meteorological and anthropogenic factors.

How to cite: Tsai, C., Chiu, Y.-K., Fu, C.-H., and Hsu, Y.-W.: Sustainable Water Consumption Strategies in a Changing Climate, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17003, https://doi.org/10.5194/egusphere-egu24-17003, 2024.

In Spain, from 2004 to 2021, irrigation has increased by 500,000 hectares, the percentage of cultivated land with irrigation has increased from 18% in 2004 to 23% in 2021. The literature points to intensive irrigated agriculture as one of the main causes of the destruction of biodiversity, the worsening of the quality of water bodies, changes in the rural economy, among others. The study analysis the dynamics of land use changes in Spain particularly in irrigated crops, from 2004 to 2021 at provincial level. It aims to understand and promote sustainable land use transitions by identifying factors influencing farmers' decisions in altering land use and crop surfaces. To this end, several public open-access databases were used to analyse, on one hand, the land use changes at a detailed level, and on the other hand, guided by the literature to examine the factors behind the observed land use change. Findings reveal agricultural intensification trends in Spain, marked by the abandonment of less productive croplands and the intensification of highly productive lands, through the implementation of irrigation. The intensification, driven by the introduction of irrigated woody crops, mostly olives, vineyards, and almonds, predominantly occurred in the water-constrained southern region of the country. This was achieved by overcoming water limitations through increased exploitation of groundwater, and the widespread adoption of drip irrigation technology. Additionally, market trends driving increased demand for these commodities and changes in the Common Agricultural Policy (CAP) have further contributed to their expansion. We explain why some provinces intensify, via more irrigated and intensive crops, and reduce cultivated land, whereas others intensify and expand the total cultivated land. The study suggests that agricultural land change is a complex dynamic process, resulting from a combination of policy impact, market incentives, mature technologies, available resources and changing climate.

How to cite: Arbonès Domingo, G., De Stefano, L., and Garrido, A.: Explaining agricultural land use changes in Spain (2004 – 2021): Markets, climate and water resources., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-391, https://doi.org/10.5194/egusphere-egu24-391, 2024.

Rainfall accumulation during wet seasons in Northern South America can be enhanced during La Niña ENSO phases.  Leptospirosis is a zoonotic waterborne disease that affects humans, domestic animals, and wildlife associated with occupational and recreational water activities, natural disasters, and socioeconomic conditions for which rainfall plays a key role in its transmission. We analyzed the incidence of leptospirosis, and relative risk of changes on the incidence of the disease due to rainfall accumulation in Northern Colombia during the period 2007-2021. The rainfall accumulation analysis was done for 7, 14 and 21 days based on the periods of incubation of the disease, biology of transmission, and thresholds of rainfall accumulation above the mean values. We found a statistically significant association between excess rainfall and leptospirosis at different lags for cities in Northern Colombia (Barranquilla, Santa Marta, Cartagena) and the levels of accumulated rainfall exceedance associated with leptospirosis were specific for each city. Our findings give insight into the association between leptospirosis and excess accumulated rainfall and provide climate services and local health authorities with tools to act on and prevent this important zoonotic disease.

How to cite: Builes-Jaramillo, A., Arias-Monsalve, C. S., Valencia, J., Florian, C., and Salas, H. D.: Rainfall accumulation as a driver of higher Leptospirosis risk in northern South America, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-697, https://doi.org/10.5194/egusphere-egu24-697, 2024.

Environmental protection is of global interest to earth’s inhabitants with increasing concerns related to climate change. Solid wastes constitute an undeniable source of environmental degradation and a possible disaster to human health. In Jos Metropolis, a number of arable lands double as waste dumpsites and are at risk of heavy metal pollution. Shallow groundwater used for domestic purposes and plants cultivated near these dumpsites are prone to contamination and the prolonged consumption of unsafe concentrations of heavy metals through edibles and/or water may trigger numerous biochemical alterations in the human body. Subsurface geophysical investigation using 2D electrical survey and the assessment of soil and water quality has been carried out in the arable land and at close geological proximity to a solid waste dumpsite located at Utan, Jos, Plateau State, Nigeria. This study focus on delineating the lateral extent and depth of leachate migration into the subsurface from the waste dumpsite. 2D resistivity survey was carried out along three traverse (A, B and C) using Wenner–Schlumberger configuration. Qualitative interpretation of the inverse resistivity models revealed low resistivity zones of < 44 Ωm to be regions of leachate accumulation. The extent of downward migration through the vertical stratigraphic interval exceeds 15.6 m trending laterally in the eastern direction of traverse A. The analysis of heavy metal determination for water samples was aided by the use of Atomic Absorption Spectrophotometer while the soil samples were analyzed using X-ray fluorescence (XRF) analytical method. The concentrations of Pb and Ni in the analyzed water samples were above the permissible limit for drinking water and concentration of heavy metals in soil samples varies significantly. This study revealed the concentration of heavy metals in soil and water samples in close geographical proximity to the waste dumpsite and the uncontrolled disposal of waste over time poses great threat to the environment and its inhabitants. Waste management practices have to be improved upon to mitigate pollution.

How to cite: Obasuyi, F. O., Oladimeji, A. M., and Yusuf, T. A.: Investigation of the lateral extent and depth of contamination using 2D electrical resistivity and the assessment of soil and water quality in the vicinity of a Waste Dumpsite in Utan Jos, Plateau State. Nigeria., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1287, https://doi.org/10.5194/egusphere-egu24-1287, 2024.

In this field pot study, effect of irrigation practice (continuous flooding (CF) and intermittent drainage (ID) treatment) on greenhouse gas (GHGs, CO₂ and CH₄) emission was determined from three Korean paddies (BG, MG, and JS series), varying soil properties such as soil texture, labile carbon, and mineral types.  Emission of GHGs was evidently influenced by irrigation practices, to a different extent, depending on paddy’s redox response to flooding events.  The Eh decline upon flooding was slower in JS pot, where pore-water concentration of ferric and sulfate ions is the highest (~ up to 3-fold) among three paddies.  MG pot was 2- to 3-fold percolative than others and the Eh drop during flooding period was the smallest (remaining above -50 mV) among three pots.  By adopting ID, CH₄ emission (t CO₂-eq ha-1 yr-1) was reduced in a wide range by 5.6 for JS pot, 2.08 for BG pot, and 0.29 for MG pot relative to CF, whereas CO₂ emissions (t CO₂-eq ha-1 yr-1) was increased by 1.25 for JS pot, 1.07 for BG pot, and 0.48 for MG pot due to the enhanced carbon oxidation upon drainage.  Grain yield and aboveground biomass production from ID were no less than those from CF (p < 0.05).  Consequently, benefit of global warming potential (S GWP) by ID varied as in order of JS (37%) > BG (14%) > MG (~0 %) pots, and negligible effect observed for MG pot was due to the equivalent trade-off between CO₂ and CH₄. Our findings imply that that the efficacy of drainage on GHG mitigation depends on the redox response of paddies.

Keyword

Climate Change, Greenhouse gas, Paddy, Intermittent drainage

Acknowledgement

This research was in part supported by the Korea Environment Industry & Technology Institute (KEITI), funded by Korea Ministry of Environment (MOE) (No. 2022002450002 (RS-2022-KE002074)) and in part supported by Korea University Grant.

How to cite: Hyun, S., Hwang, W., Park, M., An, Y.-J., Hong, S., and Jeong, S.-W.: Effect of intermittent drainage on the emission of two greenhouse gases (CO2 and CH4) from three paddies in South Korea, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2496, https://doi.org/10.5194/egusphere-egu24-2496, 2024.

Agricultural development in Kinmen region has long suffered from the absence of a corresponding management unit responsible for irrigation planning and infrastructure maintenance, resulting in the majority of local farmlands relying on natural rainfall for cultivation. Unfortunately, this method is highly susceptible to the impacts of climate change. To address this pressing issue, the government plans to utilize reclaimed water from domestic sources as a supplementary irrigation resource. Within this context, this study aims to devise an irrigation water allocation model to optimally harness the limited water resources.

In this study, we simulate the crop rotation of local sorghum and wheat, considering soil, crop, and historical meteorological data. We calculate the variations in crop yield under different irrigation schemes. Additionally, we use historical meteorological data from Kinmen to calculate various simulated climates, testing the benefits of this irrigation plan under more extreme weather conditions. In conclusion, guided by the simulation outcomes and considerations of factors like cost and government procurement prices, we undertake a comparative analysis of the economic benefits under various scenarios and irrigation plans. This analysis aims to pinpoint the optimal irrigation water allocation plan that can be feasibly implemented by local farmers.

For this study, we have chosen a 100-hectare demonstration area located in Jinsha Town, Kinmen, as our study area. We will utilize 750 tons of reclaimed water provided daily by the Ronghu Water Resources Recycling Center as the irrigation water source, and the government has already established six agricultural ponds in the area to store water. Following this, our study will proceed with the implementation of the irrigation water allocation plan in the designated demonstration area. Our ultimate aim is for this initiative to serve as a starting point, enabling the systematic expansion of the irrigation water allocation plan to other regions in Kinmen, thereby enhancing the overall irrigation quality.

Keywords: Irrigation Water Allocation Model; Reclaimed Water; Rotation Irrigation; Kinmen; Sorghum

How to cite: Su, Y., Yu, H.-L., and Chang, T.-J.: Agricultural Irrigation Water Allocation Planning and Economic Benefit Assessment – A Case Study of Kinmen County, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2737, https://doi.org/10.5194/egusphere-egu24-2737, 2024.

Agricultural produce’s yield can be heavily impacted by changes in the weather patterns. With the current global warming scenario, the extremes temperature anomalies are expected to occur more frequently, posing a significant threat to the crop yields. To better plan the agricultural practices and crop rotation, it would be highly beneficial to understand the impact of temperature anomalies on crop yields. Here in this study, we investigated the impact of changing air temperature extremes on the yields of strawberries in farms in California's Central Valley. By using a copula modeling framework, the study has identified the risks of crop yield loss associated with temperature extremes. Based on this analysis, various scenarios of crop yield loss have been identified, and the likelihood of encountering those scenarios based on changes in temperature extremes has been estimated. The results of this study can be immensely helpful in planning agricultural practices and implementing appropriate measures to mitigate the risks. With air temperature forecasts readily available from various sources, nature-based solutions can be effectively implemented to combat the negative effects of temperature extremes on crop yields.

How to cite: Unnikrishnan, P., Ponnambalam, K., and Hipel, K.: Estimating the risk of crop yield loss due to changing regional air temperatures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3235, https://doi.org/10.5194/egusphere-egu24-3235, 2024.

Vegetation restoration such as human-induced and natural growth has seen a significant increase over the past two decades. However, this surge has raised concerns regarding its potential impact on water resources and its consequential hindrance to local social and economic development. Policymakers are particularly focused on mitigating the negative hydrological effects of vegetation restoration. Nevertheless, the implications for water yields in the context of forest management types, such as planted and natural forests, remain unclear. In this study, we explored hydrological responses to forest expansion in both planted and natural forest watersheds, utilizing evapotranspiration data synthesized from 12 data products, forest management maps, and climate datasets. Our analysis, based on the Budyko framework, revealed that water yield reduction in arid watersheds with planted forests (PFs) exceeded that in watersheds with expanding natural forests (NFs). Interestingly, vegetation restoration, whether in PFs or NFs watersheds, could even lead to an increase in water yield. Attribution analysis highlighted ecological restoration, rather than climate conditions, as the primary contributor to the observed water yield decrease. In NFs watersheds, the decrease was primarily linked to underlying characteristics, while in PFs watersheds, changes in water yield sensitivity to the land surface played a crucial role. It is noteworthy that vegetation restoration in humid zones exhibited a negligible impact on water yield. Even in NFs watersheds where water yield decreased due to tree cover expansion in drylands, natural growth emerged as a viable option to mitigate local hydrological effects in arid zones.

How to cite: Yan, Y., Liu, Z., and Jaramillo, F.: The distinct hydrological responses to vegetation restoration between planted and natural forests watersheds, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3708, https://doi.org/10.5194/egusphere-egu24-3708, 2024.

The study focuses on assessing the impact of climate change on water balance components in the Upper Ghatprabha River Basin in India. The Soil Water Assessment Tool (SWAT) is utilized to simulate streamflow in the basin. Calibration and validation of SWAT are performed across multiple sites using the Sequential Uncertainty Fitting Algorithm (SUFI 2). Performance assessment relied on metrics such as the Nash-Sutcliffe efficiency (NSE) and coefficient of determination (R²). Future climate projections are based on an ensemble mean of 13 bias-corrected GCM models for the Shared Socioeconomic Pathways (SSP) scenarios SSP245 and SSP585. The simulation of future basin water balance components involves segmenting the entire timeframe into S1 (2015-2040), S2 (2041-2070), and S3 (2071-2100). Projections indicate an increase in maximum and minimum temperatures, with precipitation potentially rising by up to 47% in the basin under the SSP245 scenario by the end of the century. Hydrological simulations reveal increased surface runoff and evapotranspiration under the SSP245 scenario compared to historical data. The percentage change in blue water components under both SSP scenarios shows an increase of more than 50% compared to the historical data. In comparison, that of green water components only increases to a maximum of 8% in all the timeframes (S1, S2 and S3). Notably, the impact of climate change is more pronounced under the SSP585 scenario compared to SSP245. These changes significantly impact the water resources of the Upper Ghatprabha River Basin; necessitating focused attention on future planning and management strategies for water resources.

How to cite: Jain, S. and Jain, M. K.: Assessment of Blue and Green Water Availability in the Upper Ghatprabha River Basin under Climate Change Impacts, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4988, https://doi.org/10.5194/egusphere-egu24-4988, 2024.

Durum wheat is a critical staple crop in arid and semi-arid regions worldwide, that plays a significant role in local food security. Providing essential nutrients and a high protein content, it is widely used for the production of pasta and couscous. Various constraints and drivers affect durum wheat productivity, including biotic and abiotic stressors, agronomic practices, and CO₂ concentrations. Their influence varies based on duration and intensity of the stressor, as well as the durum wheat growth phase in which they occur. Drought and heat were shown to act as primary yield limiting factors. Furthermore, the water footprint, a comprehensive measure for the volume of water associated with crop production, helps to analyse durum wheat cultivation from a water-food nexus perspective. Given that climate change is affecting the main influencing factors of durum wheat’s productivity and of its water footprint, such as precipitation, temperature, and atmospheric CO₂ levels, its cultivation is expected to undergo alterations as well. In this context, we explore the present state of durum wheat productivity and the potential influence of changing climatic conditions on its future cultivation worldwide. The current state of research on future durum wheat production is characterised by contradictory results, compromising projections of significant declines due to heat and drought stress as well as strong increases in productivity as a consequence of the CO₂-fertilisation effect, for the same or nearby locations. Understanding the complex interactions between climate change, durum wheat productivity and the associated water footprint is of great importance to derive sustainable adaptation strategies and move one step closer into ensuring future food and water security.

How to cite: Grosse-Heilmann, M., Cristiano, E., Viola, F., and Deidda, R.: Influencing factors of durum wheat productivity under current and future climatic conditions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5462, https://doi.org/10.5194/egusphere-egu24-5462, 2024.

Mobile phones, televisions, computers and other liquid crystal devices have become the electronic products widely used by humans in modern society. Liquid crystal monomers (LCMs) are the key material of liquid crystal display and considered as potential persistent, bioaccumulative, and toxic (PBT) substances in recent years, but there is a limited of information regarding their occurrence in human body. We used EPI suite software from USEPA to evaluate its physical and chemical properties, analyzed its concentration in serum and urine by GC-MS, and finally assessed its health risk to humans through the calculation of daily intake. In this paper, 15 LCMs were detected in serum and urine samples of the general population, with median concentrations ranging from 9.7 to 124.8 and 2.68 to 36.98 µg/L, respectively. The correlation of LCM in serum and urine suggests that they have potential common applications and similar sources. The results showed that the CLrenal of LCMs in the Northwest China population was 0.61, 7.79, 6.04, 4.81, 9.37, 4.85, 19.94, 10.64, 3.80, 7.44, 8.26, 15.39, 7.52, 10.17, 13.54 mL/kg/day for EBCN, BCBP, PBIPHCN, DFPrB, FPrCB, BEEB, BMBC, DFPCB, DFEEB, EPrCPB, EEPrTP, EDFPB, DFPrPrCB, EFPeT, TeFPrT, respectively. The daily intake for ∑LCMs in the adult of northwest China was 22.35 ng/kg bw/day, indicating a potential exposure risk to the general population. This study provides the first evidence for the presence of LCM in serum and urine in the daily population and finds a correlation between LCMs, but the differences in B/U ratio and renal clearance indicate the need for further investigation of its metabolism and clearance in the human body.

How to cite: Yang, K., Cheng, H., Quan, W., Gong, Y., and Ai, Y.: Human health risks estimations from Liquid crystal monomers（LCMs）in Northwest China : partitioning, clearance and exposure in paired human serum and urine, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7771, https://doi.org/10.5194/egusphere-egu24-7771, 2024.

Abstract : Irrigated olive trees constitute the main arboricultural component of orchards in semi-arid regions, and the optimization of irrigation practices is crucial to sustain the production, increase agricultural water productivity and reallocate water savings to other higher-value uses. Numerous technical strategies have been implemented in the last two decades, to promote water conservation in irrigated agriculture, namely the adoption of subsurface drip irrigation system. This study delves into a comprehensive comparative analysis between subsurface (SDI) and surface (DI) drip irrigation systems over an olive orchard, with an emphasis on the evolution of evaporative fraction (EF) and the ratio of transpiration (T) to evapotranspiration (ET), soil moisture distribution patterns, as well as water use efficiency and water productivity. The experiment was carried out over two irrigated olive plots located in the Tensift basin (Morocco), from May to October 2022. Each plot is subjected to a specific irrigation pattern, and equipped with an Eddy-Covariance system to quantify the energy balance components, along with Time-Domain-Reflectometry (TDR) sensors installed at various depths, to monitor the soil water content. Besides, the partitioning of ET into T and evaporation (E) over the two irrigation systems was performed using the Conditional Eddy-Covariance (CEC) scheme and validated using sap flow measurements collected over SDI plot during April 2023. The ET of the DI system was higher than that of the SDI one, with diurnal ET values ranging between 0.58-3.02 (mm/day) and 0.48-2.74 (mm/day) for DI and SDI systems, respectively. Our findings suggest that although a smaller irrigation water amount was applied in SDI (194 mm) compared to DI (320 mm), crop yield revealed no significant differences. This thorough assessment intends to add substantial knowledge to the lasting debate about sustainable irrigation practices over olive orchards and assist policymakers in making informed decisions to enhance water use efficiency while sustaining overall agricultural production.

Keywords: subsurface and surface drip irrigation; evapotranspiration; water productivity; water use efficiency; olive trees; semi-arid areas.

How to cite: Ourrai, S., Aithssaine, B., Amazirh, A., Er-raki, S., Bouchaou, L., Jacob, F., Kharrou, M. H., and Chehbouni, A.: Optimizing irrigation practices for sustainable olive production in semi-arid areas: A comparative analysis of the efficiency of Subsurface and Surface drip irrigation systems , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8378, https://doi.org/10.5194/egusphere-egu24-8378, 2024.

Climate change and water scarcity has pushed more countries with direct ocean access to seek desalination solutions to face part of their need for domestic water networks or industrial usage, while conserving coastal ecosystems. Seawater monitoring is crucial in implementing a desalination plant as it ensures the efficiency and sustainability of the desalination process, especially in the case of a plant powered by renewable energy sources. Seawater is the main input of desalination processes and coastal areas are the locations of the release of the salty waste. An autonomous buoy can be used to monitor the seawater parameters which are essential to sizing a desalination plant.

There have been recent developments of autonomous buoy systems for monitoring different water parameters, however lacking in certain aspects. Some of the elements of these buoys include limited range of data transmission, high-cost designs, immobility and limited number and types of sensors. Also, there has been lacking implementation of autonomous buoys used in development of desalination plants. 

The proposed low-cost autonomous buoy is designed and constructed using cost effective materials. It increases the possibility of multiplying the sensor count to have a more accurate data mapping system. The low cost provides the opportunity of having more devices where there is a higher probability of equipment loss due to possible theft or remoteness of travel. The power supply is an oversized solar array with a backup battery and solar charger. An Arduino microcontroller is connected to two probes and a GPS sensor. The data is logged on a SD memory card with data transmitted via the Iridium satellite constellation, consisting of 75 satellites. There are two parts of construction involved in the project: the construction of the outer shell of the buoy and the design of the inner circuitry and components. The project involves multiple steps of experimentation: first in a laboratory/controlled area then deployed in the Seto Inland Sea, Japan. The various steps ensure the data collected by the sensors is reliable, valid, and suitable for scientific research. After this successful implementation, the buoy will be adapted and deployed in the Caribbean Sea surrounding Jamaica.

Initial results show a promising possibility of measuring seawater parameters such as GPS location, salinity, and sea surface temperature for any body of water. Utilizing the span of the Iridium satellite communication system, this ensures that virtually all regions of the Earth can be measured. The sizing of the solar powering components allows for at least 1 year of monitoring in the worst-case scenario and 4-5 years in the best-case scenario. The integration of autonomous buoys in the desalination process enhances efficiency in the plant design stages and reduces potential costs which contributes to the optimization of the desalination system. The environmental integration and the operation of the plant will be improved as a result of the enhanced assessment of the input and waste release conditions.

Keywords: Seawater Monitoring, Remote Sensing, Desalination, Autonomous buoy, Autonomous measurements

How to cite: Williams, Z., Soto Calvo, M., and Lee, H. S.: Design of a low-cost autonomous seawater measurement buoy to scale and optimize a green-powered desalination plant, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8539, https://doi.org/10.5194/egusphere-egu24-8539, 2024.

Reduced rainfall has been identified as a highly probable consequence of climate change in certain regions of Zambia. This is particularly concerning for small-holder farmers, who heavily rely on rainfall and are the primary producers of the country’s staple food, such as maize. The resulting decrease in production significantly impacts national food security. Recognizing the potential of irrigated agriculture to improve food security and sustain production levels, the Zambian Agricultural Research Institute (ZARI) has been actively engaged in research since 2021. Their focus is on enhancing irrigation and soil fertility management under conditions of reduced water availability.

To address these challenges, a research trial was initiated at the ZARI research station in 2021. This trial aims to identify the optimal and sustainable water and nitrogen application for achieving maximum maize production in irrigated crop systems. Access tubes were installed in each subplot to monitor soil moisture to a depth of 1 m before and after irrigation on a weekly basis.

This paper assesses the stored water in the root zone (up to 1 m) with interplay between amount of nitrogen fertilizer  applied and water application level.

In the 2021 season, the results indicate that significantly more water was retained averagely throughout the growing season  in treatments with higher nitrogen levels, especially under reduced irrigation water applications (50% and 75% ETc). A similar trend was observed in the 2022 season, albeit only for 50% ETc. The increased stover yield may have contributed to reduced evaporation, minimizing losses. As nitrogen application levels rise, the ability to store soil water in the profile appears to increase. However, further analyses of soil moisture depth and root systems are needed to determine whether excess water in deficit-irrigated treatments is obtained from lower depths or if (and how much) water is lost in optimally irrigated treatments.

How to cite: Mwape, M., Said Ahmed, H., Phiri, E., and Dercon, G.: Enhancing Maize Production in Irrigated Crop Systems: Optimizing Water and Nitrogen Application for Sustainable Agriculture in Zambia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8734, https://doi.org/10.5194/egusphere-egu24-8734, 2024.

Climate change is threatening food security. To ensure food security, we do not only have to safeguard agricultural production - crop yields also need to be optimally distributed. For that, decision-makers need reliable crop forecasts so that they can plan which regions are likely to experience crop yield losses and which regions will produce a surplus. Earth observation and machine learning are key tools to calculate such forecasts. However, extreme crop yield losses, for example caused by severe droughts, are often underestimated. To test this, we developed a machine learning-based crop yield anomaly forecasting system for the Pannonian Basin and examined its performance, with a focus on drought years. We trained the model (XGBoost) with crop yield data from 43 regions in southeastern Europe and predictors describing soil moisture, vegetation, and meteorological conditions. Maize and winter wheat yield anomalies were forecasted with different lead times (zero to three months) before the harvesting season. Our results show that the crop yield forecasts are significantly more reliable from 2 months before the harvest than before in both, drought and non-drought years. The models have their clear strength in forecasting interannual variabilities but struggle to forecast differences between regions within individual years. This is related to spatial autocorrelations and a lower spatial than temporal variability of crop yields. In years of severe droughts, the wheat yield losses remain underestimated, but the maize forecasts are fairly accurate. The feature importance analysis shows that in general wheat yield anomalies are controlled by temperature and maize by water availability during the last two months before harvest. In severe drought years, soil moisture is the most important predictor for the maize model and the seasonal temperature forecast becomes key for wheat forecasts two months before harvest. 

How to cite: Bueechi, E., Fischer, M., Crocetti, L., Trnka, M., Grlj, A., Zappa, L., and Dorigo, W.: Food security in a changing climate - how can Earth observation and machine learning help? , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9386, https://doi.org/10.5194/egusphere-egu24-9386, 2024.

The demand for farmland products is increasing worldwide, causing unprecedented stress on the global agricultural system and, consequently, on water resources. Here we analyse the impact of drought events on rainfed agriculture, a topical issue given the prolonged and severe drought events currently occurring around the world and thus including highly productive areas. We investigate the agricultural yields of key crops that represent 61% of the world’s production of proteins for human consumption (i.e. corn, wheat, rice, and soybeans). Our analysis spans from the early 1900s to 2022, allowing us to assess the total agricultural area under drought stress per year and the most vulnerable types of crops. We identify significant trends in the extent of agricultural land under stress, considering both historical and recent periods. This comprehensive analysis enables us to estimate the frequency of occurrences of crop-specific cultivated areas under stress over time, unravelling the pattern of drought impact on global agriculture.

How to cite: Rinaldo, T., Ridolfi, E., Moccia, B., Marconi, F., D'Odorico, P., Russo, F., and Napolitano, F.: The impact of drought on the water-food nexus at the global scale, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13506, https://doi.org/10.5194/egusphere-egu24-13506, 2024.

Continued population growth, changing climate and increased pressure on water resources will dramatically increase the pressure on Chinese agriculture in the coming decades. Although there have been some reports of yield stagnation in the world’s major cereal crops, including maize, rice and wheat, the reasons for stagnation have not been quantified thoroughly. Here, we use statistical data to examine the trends in crop yields for two key Chinese crops: maize and wheat and their drivers in China’s drylands. Results showed that although yields continue to increase in many areas, we found that across 70.2% of maize- and 51.9% of wheat- growing prefectures or provinces, yields either never improved, stagnated or collapsed. The reasons for the decline and stagnation of crop yield were mainly caused by the change of growing season precipitation and irrigation fraction. New investments such as increased irrigation fraction in underperforming regions, as well as strategies to continue increasing yields in the high-performing areas, are required.

How to cite: Zi, S.: Recent patterns of crop yield growth, stagnation and their drivers in China’s dryland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13868, https://doi.org/10.5194/egusphere-egu24-13868, 2024.

Agriculture is highly dependent on climate because rainfall, temperature and sunlight are the primary determinants of crop development. Climate change driven effects such as variation in precipitation and changes in temperatures are likely to affect agricultural yields. Systematic planning of agricultural activities considering these effects is essential. As a first step towards this longer term objective, this work quantifies the effect of climate change on crop in short and long term in India. Wheat is chosen as the crop of interest. Madhya Pradesh, one of the leading wheat producing states in India, is the region under focus, and Betul district is selected for a initial studies. The CERES-wheat model in the Decision Support System for Agrotechnology Transfer (DSSAT) tool is used to estimate the impact of climate change on wheat yield. The CERES-wheat model has been calibrated and validated, and the calibrated parameters have been used to simulate wheat yield in the future. The base period for calculating base wheat yield is 2009-2019. Future wheat yields are calculated for two periods (2025-2055 and 2056-2085). The projected changes in precipitation, maximum temperature (Tmax) and minimum temperature (Tmin) in future compared to the base period are calculated using four different General Circulation Models (GCMs) and four Shared Socioeconomic Pathways (SSPs). To increase the study's robustness, 1000 samples are systematically generated using Latin Hypercube Sampling (LHS). A stochastic weather generator (WG), WeaGETS, is used to create a synthetic time series of climate variables. Using the 1000 different combinations of changes in climate variables, 1000 climate scenarios are generated using WeaGETS. The climate variables used to determine the relationship between climate and wheat yield were mean rainfall, rainfall variance, Tmax, and Tmin. Wheat yield ranged from 2065 to 3207 kg/ha during the baseline period, and it is expected to vary from 1629 to 3638 kg/ha between 2025 and 2055. Looking ahead to 2056-2085, wheat yields are estimated to range from 1363 to 3555 kg/ha. The sensitivity analysis results between climate variables and wheat yield for both periods suggest that wheat yield is positively correlated with mean rainfall and rainfall variance and negatively correlated with Tmax and Tmin. Maximum temperature has a significant negative correlation with wheat yield in both periods after excluding the effect of other climate variables. However, in the last stage of wheat yield development, the grain filling stage, Tmin is more critical than Tmax. These results highlight the need for systematic planning to manage negative impacts of climate change on wheat cultivation in India. These results will used as a basis for suggesting adaptation strategies to manage the impact of climate change on wheat yield.

How to cite: Lakshmanan, A., Shastri, Y., and Singh, R.: Climate change impact on wheat yield in India: Study using CERES-wheat model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18617, https://doi.org/10.5194/egusphere-egu24-18617, 2024.

The Canary Islands constitute an archipelago of Spain, also being a European outermost region composed of eight islands. Overall, these islands face a high risk of experiencing the impacts of climate change, particularly rising sea levels, floods, temperature increases, and a decrease in water resources, factors that significantly affect the daily life of the population in the islands. As the effects of climate change are linked to greenhouse gas emissions, it is crucial to measure the emissions from the main sectors of the Canary Islands to implement effective mitigation and reduction measures, as well as to increase energy production through renewable sources. For this reason, the Government of the Canary Islands has commissioned the project to determine the carbon footprint and water footprint of the main sectors of the region, including the production of drinking water and wastewater management, agriculture, and tourism. The results indicate that seawater desalination for drinking water, being a significant energy consumer with low penetration of renewable energy in the Canary Islands' electricity mix, is the facility contributing the most to greenhouse gas generation in the water cycle in the region. It is followed by wastewater treatment plants and extraction wells from the aquifer. In the case of agriculture, focusing on the consumption of tropical crops such as avocados and bananas, key export crops, it is noteworthy that avocados are major water consumers, slightly exceeding the water consumption of bananas. This poses challenges in the face of an uncertain future due to reduced natural precipitation resulting from climate change. Lastly, the analysis of tourism emissions highlights that hotel activities and rental vehicles are significant contributors to greenhouse gas emissions. Although these emissions are indirect for the archipelago, other studies have emphasized the high emissions associated with the arrival of tourists by air to the islands. This study stands as the first to analyze the emissions of the main sectors in the Canary Islands, providing an opportunity for governmental actions to reduce these emissions and mitigate climate change in the islands.

Keywords: Climate change; outermost region; vulnerability; sustainable development

Acknowledgements

This research was supported by the European Union's Horizon 2020 Research and Innovation Programme under grant agreement 101037424 and Project ARSINOE (Climate Resilient Regions Through Systems Solutions and Innovations).

How to cite: Santamarta, J. C., Cruz-Pérez, N., Rodríguez-Alcántara, J. R., Rodríguez-Martín, J., García-Gil, A., Gasco-Cavero, S., and Marazuela, M. Á.: Estimating and Suggesting measures to reduce carbon emissions and water footprint linked to water collection, agriculture, and tourism in the Canary Islands (Spain), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19902, https://doi.org/10.5194/egusphere-egu24-19902, 2024.

The global food supply and food security are altered by field, soil, and weather conditions during crop production. Researching food productivity became crucial as the global population increased. In particular, crop losses bring low food supply and price instabilities at the regional and global levels. With that in mind, we reviewed ten crop models and the most simulated impacts from soil-crop-atmosphere interactions in maize, rice, and wheat production. Since 2012, modellers have mainly used APSIM to predict water availability, temperature changes and Greenhouse Gas  (GHG) concentration to predict crop phenology, growth and development, grain filling and nutrient content, and yield. Since 2013, AquaCrop has been used to simulate scenarios focused on water balance in crop production systems, water stress and irrigation planning. Interestingly, Biome-BGCMuso was developed as a biogeochemical model and was not considered good by crop modellers. However, After updates, version v6.2 can simulate different management and field conditions for fifteen crops, considering heat, nitrogen and drought stress. Since 2008, crop modellers used CropSyst to evaluate water availability, nitrogen use efficiency (UE), temperature shifts and GHG concentration in rainfed and irrigated crop systems. Since 2002,  crop modellers have used DAISY to predict crop growth, nitrogen and water UE, grain content, yield gap, and losses. Since 2011, researchers have used DSSAT-CERES for mitigation strategy planning by predicting crop growth, soil characteristics, changes in land use, and nitrogen and water UE. Since 2015, JULES has been used to determine land-atmosphere interactions, changes in land use and GHG impacts on agriculture. Since 2008, ORYZA modellers have mainly predicted nitrogen and water UE, salinity impacts, and toxicity to rice. STICS was developed in 1996, and since 2008, it has been primarily used to simulate fertilization and irrigation systems, nitrogen leaching, and water availability. Since 2000, researchers have used WOFOST to analyze water availability, crop growth, and productivity under temperature changes. Crop models are fast and reliable resources when simulating crop production and food availability.

How to cite: Gavasso Rita, Y., Papalexiou, S., Li, Y., Elshorbagy, A., Li, Z., and Schuster-Wallace, C.: The use of crop models to assess crop production and food security, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20643, https://doi.org/10.5194/egusphere-egu24-20643, 2024.

Estimating crop yield can help farmers plan for equipment, labor, and other crop production input requirements. Forecasting crop yield is also useful for analyzing weather-related variability to guide decisions such as irrigation water and fertilizer management. This work discusses the application of Gated Recurrent Unit (GRU) and Long Short-Term Memory (LSTM) machine learning algorithms for seasonal cotton yield prediction. Simulation results from the crop model AquaCrop, consisting of irrigation depth, soil moisture content, and crop growth stage data from 2003 to 2021 were used to train the algorithms. The two developed yield-prediction models were tested against data collected from an irrigated cotton field located at Clemson University Edisto Research and Education Centre (EREC), near Blackville, South Carolina, USA during the 2023 growing season. The values of hidden layers, hidden units, dropout, learning rate and batch size hyperparameters were set to respectively, 3, 64, 0.2, 10E-3 and 64 for the GRU model and 3, 128, 0.4, 10E-3 and 64 for the LSTM model. Analysis suggested that the tested algorithms resulted in very good to excellent performance. We concluded that machine learning algorithms are useful tools that can provide insights into how much yield to expect in an upcoming season and help farmers optimize energy, water, and fertilizers applications.

How to cite: Umutoni, L., Samadi, V., Payero, J., Koc, B., and Privette, C.: Application of Machine Learning Approaches for Cotton Seasonal Yield Estimation , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20876, https://doi.org/10.5194/egusphere-egu24-20876, 2024.

Climate change is expected to impact the maritime sector, including the port industry. Ports are on the frontline when it comes to experiencing operational challenges from the increased sea levels and extreme weather conditions, associated with increased infrastructure investments. For instance, rising sea water levels are expected to change the accessibility of channels and increase the need for higher quay walls, while the increased intensity or/and frequency of events, such as fog, high winds, and waves, may increase the frequency of port operation disruptions; but changes are uncertain, and with regional variation.

The present study focuses on the Port of Heraklion, one of the main ports of national importance in the Greek Maritime Network, located in the North side of the island of Crete, and aims at assessing the impacts of climate change on port operations associated with: 

• Changes in mean sea level, storm surges and wave characteristics (i.e. wave height, period, frequency of occurrence).
• Reduced visibility caused by intense precipitation and/or fog.
• Disruption of port operations due to high wind speeds, drainage system induced flooding, as well as river discharges and sediment transfer in the harbor basin.

To assess the effects of climate change on winds we use climate change factors (CCFs) obtained using climate model data at 3-hourly temporal resolution over the Island of Crete (i.e. sub-country level) from EURO-CORDEX ensemble, and more in particular from HIRHAM5 RCM (Regional Climate Model) nested in (downscaled from) EC-EARTH GCM (Global Climate model), for two Representative Concentration Pathways of future emissions: RCP 4.5 for the period 2071-2100 and RCP 8.5 for the period 2041-2070. These are also the RCM-GCM combination and time periods used to assess the effects of climate change on the sea state and wave characteristics.

For rainfall, we make direct use of the climate change factors reported in the context of SWICCA program (Service for Water Indicators in Climate Change Adaption, 2015 - 2018), which was financed by the European Centre for Medium-Range Weather Forecasts (ECMWF) on behalf of the European Copernicus Agency within the framework of the Copernicus climate change service (C3S). Over the island of Crete, the corresponding factors are available for 9 GCM - RCM combinations (i.e. 5 for the RCP 4.5 scenario and 4 for the RCP 8.5 scenario).

We find that the increase of the mean sea level, as well as the increase in the frequency of intense storms significantly affect the frequency of port operation disruptions, particularly due to breakwater overtopping, storm induced flooding, as well sediment deposition in the harbor basin.

Acknowledgements

The presented work has been conducted under the project Climate Risk and Vulnerability Assessment (CRVA) for the Heraklion Port Authority" (project code: AA 011391-002/CC15302), which has been financed by the EIB under the InvestEU Advisory Hub. 

How to cite: Perdios, A., Boutatis, A., Langousis, A., Biniskos, P., Kypraiou, E., Korda, K., and Zacharof, A.: Climate Risk and Vulnerability Assessment (CRVA) for the Port of Heraklion in Greece , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21145, https://doi.org/10.5194/egusphere-egu24-21145, 2024.

Because of their computational expense, models with comprehensive tropospheric chemistry have typically been run with prescribed sea surface temperatures (SSTs), which greatly limits the model’s ability to generate climate responses to atmospheric forcings. In the past few years, however, several fully coupled models with comprehensive tropospheric chemistry have been developed. For example, the Community Earth System Model version 2 with the Whole Atmosphere Community Climate Model version 6 as its atmospheric component (CESM2-WACCM6) has implemented fully interactive tropospheric chemistry with 231 chemical species as well as a fully coupled ocean. Earlier versions of this model used a “SOAG scheme” that prescribes bulk emission of a single gas-phase precursor to secondary organic aerosols (SOAs). In contrast, CESM2-WACCM6 simulates the chemistry of a comprehensive range of volatile organic compounds (VOCs) responsible for tropospheric aerosol formation. Such a model offers an opportunity to examine the full climate effects of comprehensive tropospheric chemistry. To examine these effects, 211-year preindustrial control simulations were performed using the following two configurations: (1) the standard CESM2-WACCM6 configuration with interactive chemistry over the whole atmosphere (WACtl) and (2) a simplified CESM2-WACCM6 configuration using a SOAG scheme in the troposphere and interactive chemistry in the middle atmosphere (MACtl). The middle-atmospheric chemistry is the same in all configurations, and only the tropospheric chemistry differs. Differences between WACtl and MACtl were analyzed for various fields. Regional differences in annual mean surface temperature range from −4 to 4 K. In the zonal average, there is widespread tropospheric cooling in the extratropics. Longwave forcers are shown to be unlikely drivers of this cooling, and possible shortwave forcers are explored. Evidence is presented that the climate response is primarily due to increased sulfate aerosols in the extratropical stratosphere and cloud feedbacks. As found in earlier studies, enhanced internal mixing with SOAs in WACtl causes widespread reductions of black carbon (BC) and primary organic matter (POM), which are not directly influenced by VOC chemistry. These BC and POM reductions might further contribute to cooling in the Northern Hemisphere. The extratropical tropospheric cooling results in dynamical changes, such as equatorward shifts of the midlatitude jets, which in turn drive extratropical changes in clouds and precipitation. In the tropical upper troposphere, cloud-driven increases in shortwave heating appear to weaken and expand the Hadley circulation, which in turn drives changes in tropical and subtropical precipitation. Some of the climate responses are quantitatively large enough in some regions to motivate future investigations of VOC chemistry’s possible influences on anthropogenic climate change. Additional simulations of a 2000 baseline (rather than preindustrial) climate reveal that these results are sensitive to the prescribed land emissions. Most of this work was recently published in Atmospheric Chemistry and Physics (doi:10.5194/acp-23-9191-2023).

How to cite: Stanton, N. A. and Tandon, N. F.: How does tropospheric VOC chemistry affect climate? Investigations using the Community Earth System Model Version 2., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2025, https://doi.org/10.5194/egusphere-egu24-2025, 2024.

The potential transition to a hydrogen-based economy, requires a comprehensive understanding of hydrogen's atmospheric behaviour for well-informed decision-making. Among the uncertainties surrounding the atmospheric fate of hydrogen, the chemical processes governing its formation and transformation are pressing.

This study employs STOCHEM-CRI, a global 3D tropospheric chemical transport model, to explore the chemical uncertainty associated with atmospheric hydrogen. The primary objective is to improve our understanding of the hydrogen distribution, sources, and sinks on a global scale. Addressing the significant role of formaldehyde (HCHO) as a chemical source, we update its photolysis parameterisation in accordance with recent recommendations (JPL 2020 and IUPAC 2013) and assess its variability. Furthermore, we evaluate the atmospheric burden of HCHO as a function of its sources to identify key photochemical contributors to the present hydrogen budget.

The study undertakes preliminary studies of the major sink of atmospheric hydrogen, namely uptake by soil, to gauge its impact. Through a meticulous examination of model outputs against observational data, various scenarios are systematically assessed for their ability to accurately replicate global hydrogen distribution and seasonal variations.

Preliminary results show updates to the photochemical parameters of HCHO significantly reduce the hydrogen burden by between 50 and 90 ppb globally. This is namely due to updates to the quantum yield of the molecular (H2 producing) photolysis channel which varies significantly when compared to previous recommendations. There is limited variation between the two updates (JPL 2020 and IUPAC 2013) of up to 5 ppb. Additionally, minor updates relating to the temperature dependence of the soil sink result in significant improvement in the models replication of observational data, including seasonal variation.

How to cite: Holland, R., Khan, M. A. H., and Shallcross, D.: Understanding and quantifying chemical uncertainties in the hydrogen budget, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3142, https://doi.org/10.5194/egusphere-egu24-3142, 2024.

As a clean and efficient secondary energy, hydrogen energy is of great significance for energy transition and carbon neutrality. However, hydrogen development faces big challenges of high cost, unclean in production process, insecurity in transportation and storage etc. This paper tries to build a theoretical framework of hydrogen supply chain which contains whole life cycle of production, transportation, storage, utilization, and recycle of end use. Our study shows that a complete and mature hydrogen energy supply chain can enlarge the scale of hydrogen production and reduce the cost, improve its efficient and safety, and obtain a stable, sustainable, and zero-emission energy system. At the same time, a sound hydrogen energy supply chain also plays an important role in ensuring energy security and a bridge for the transition from fossil energy to renewable energy and these will help to reduce CO₂ emissions, promote carbon peaking and neutrality through energy technological innovation and rapid energy transition.

Key words: Hydrogen energy storage, hydrogen industry supply chain, green hydrogen, energy transition, carbon peaking and neutrality.

How to cite: Yukihara, T. and Sun, Q.: Hydrogen supply chain and its impacts on energy storage and carbon neutrality, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3552, https://doi.org/10.5194/egusphere-egu24-3552, 2024.

Accurate modelling of tropospheric ozone is crucial for understanding its climate and health effect, yet the uncertainty associated with natural ozone precursor emissions such as lightning and soil NO_x is often overlooked. Here we apply a global chemical transport model, GEOS-Chem High Performance, to explore this uncertainty.

The modelled present-day tropospheric ozone burden, under low to high natural NO_x emissions levels (set to align with the current literature’s range), varies from 285 to 373 Tg; primarily attributed to lightning NO_x uncertainty. Such a range far exceeds the ozone difference driven by anthropogenic emissions between the two most disparate SSP scenarios in 2050 (33 Tg). Ozone’s sensitivity to natural emissions is the highest around the tropical upper troposphere where ozone’s climate effect is also large, and would be even higher if anthropogenic emissions were reduced along the SSP1-2.6 pathway. At the surface, global mean warm-season ozone ranges from 32.4 to 38.8 ppbv, mainly due to soil NO_x. This especially introduces large ozone uncertainties in southern hemisphere regions such as the Amazon and Australia.

We also examine ΔO₃-anthro, the ozone change driven by anthropogenic emissions changes up-to 2050. We found that with respect to tropospheric ozone burden, ΔO₃-anthro shows limited differences between high and low natural emission levels (~13%), implying that the estimate of future changes in ozone radiative forcing is subject to less uncertainty from uncertain natural emissions than the present-day ozone radiative forcing itself. However, ΔO₃-anthro related to the surface ozone exposure metric shows significant contrasts with different natural NO_x emissions. The largest difference exceeds 5 ppbv (~50%) in regions such as Europe, North America, eastern China, and India. We hence stress that extra care needs to be taken when using individual models to assess ozone health risks in these densely populated regions as highly uncertain natural emissions will produce a presently unconstrained error.

How to cite: Ye, X., Wang, X., Li, D., Griffiths, P., Archibald, A., and Zhang, L.: Uncertainties in tropospheric ozone changes due to natural precursor emissions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4434, https://doi.org/10.5194/egusphere-egu24-4434, 2024.

Anthropogenic hydrogen emissions to the atmosphere have the potential to increase if there is a proliferation of hydrogen as a fuel in the future (Warwick et al., 2023).  It is well understood that atmospheric hydrogen has a positive indirect global warming potential (Ocko and Hamburg, 2022; Sand et al., 2023).  However, substantial uncertainty remains in evaluating this global warming potential, and how this value depends on the distribution of emissions.  Principally, the most appropriate surface deposition scheme to use in models remains unclear (Paulot et al., 2021).

Motivated by the observation that the seasonal variability of station hydrogen measurements (from Petron et al., 2023) can be well described as a function of latitude, we present an idealised latitude-height model for testing prototype deposition schemes.  We show how much of the key features of the seasonal variability can be captured with an illustrative benchmark deposition scheme, and finally how this model can be used to iteratively develop existing deposition schemes (e.g. Bertagni et al., 2021).

How to cite: Tardito Chaudhri, A. and Stevenson, D.: A Simple Approach for Atmospheric Hydrogen Modelling Based on the Seasonal Variability, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6038, https://doi.org/10.5194/egusphere-egu24-6038, 2024.

There are close to 6000 megaconstellation satellites in low-Earth orbit comprising 65% of all satellites orbiting Earth. The growth in satellite megaconstellations has driven surges in rocket launches and re-entry destruction of spent satellites. This has contributed to large increases in emissions of pollutants that are very effective at depleting stratospheric ozone and altering climate, due to direct injection of pollutants into the upper layers of the atmosphere where turnover rates are very slow. An additional 540,000 megaconstellation satellites are proposed, yet the environmental impacts of emissions from current and future satellite megaconstellations remain uncharacterized and unregulated. Here we calculate emissions of the dominant pollutants from megaconstellation and non-megaconstellation rocket launches and re-entries from 2020 to 2022 to determine the effect on climate and stratospheric ozone. Pollutants include black carbon (BC), nitrogen oxides (NO_x≡NO+NO₂), water vapour (H₂O), carbon monoxide (CO), alumina aerosol (Al₂O₃) and chlorine species (Cl_y≡HCl+Cl₂+Cl) from rocket launches and nitrogen oxides (NO_x≡NO) and alumina aerosol (Al₂O₃) from re-entries. Launch emissions are calculated by determining the vertical distribution of propellant consumption for each rocket stage and calculating and applying vertically resolved propellant specific emission indices that account for additional oxidation in the hot rocket plume and changes in atmospheric composition with altitude. To quantify the re-entry emissions, the mass of re-entering objects is compiled for all objects (spacecraft, rocket stages, fairings, and components) re-entering Earth’s atmosphere in 2020-2022. Many objects, accounting for 12-16% of re-entry mass, are not geolocated, so the longitude and latitude of re-entry is bounded by the reported orbital inclination. Object class and object reusability are used to define the chemical composition and mass ablation profile of each re-entering object. We find that total propellant consumed has nearly doubled from ~38 Gg in 2020 to ~67 Gg in 2022 and re-entry mass has increased from ~3.3 Gg in 2020 to ~5.6 Gg in 2022. Megaconstellation re-entries accounted for 8-12% of the Al₂O₃ and NO_x re-entry emissions in 2020-2022, due to increased megaconstellation launches and short (~2 years) lifespan of most (85%) megaconstellation satellites. Anthropogenic re-entry emissions of NO_x (~4.2 Gg) and Al₂O₃ (~0.96 Gg) in 2022 equal a third of the natural meteoritic injection of NO_x and surpass the natural injection by 7 times for Al₂O₃. The annual emissions for 2020-2022 will be used to predict the rise in emissions up to 2029 from megaconstellation and non-megaconstellation rocket launches and object re-entries for input to the 3D atmospheric chemistry transport model GEOS-Chem coupled to a radiative transfer model to simulate stratospheric ozone depletion and radiative forcing attributable to a decade of satellite megaconstellation emissions.

How to cite: Barker, C., Marais, E., and McDowell, J.: Developing inventories of by-products from satellite megaconstellation launches and disposal to determine the influence on stratospheric ozone and climate, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6467, https://doi.org/10.5194/egusphere-egu24-6467, 2024.

The European Green Deal target of zero emissions by 2050, boosted by the energy crisis due to the Russian-Ukranian conflict, put decarbonisation at the forefront of policymakers’ and industries’ development plans. Hydrogen, especially if produced by renewable energy sources, is considered one of the main candidates in the ongoing energy transition. The hydrogen economy is still in its early stages, due to the high cost of technologies, production, and infrastructure, but the electrolyser capacity installed in 2023 doubled 2022 levels (IEA report, 2023), with clear signs of increasing investments in this sector. However, large-scale diffusion of hydrogen technologies could negatively impact climate because of the increase in H₂ emissions (through leakages or other mechanisms) to the atmosphere and its interactions with other gases. Hydrogen interacts with the oxidative cycles of CH₄, NO_x, and CO, affecting natural GHG-removing mechanisms. In addition, an increase in atmospheric hydrogen could alter stratospheric levels of ozone and water vapour. Increasing H₂ emissions may result in an increase in global radiative forcing, even if H₂ replaces a proportion of fossil fuel use. However, quantification of these impacts remains uncertain and depends on the development and uptake of different hydrogen technologies. The HYDRA project, funded by the European Commission under the Horizon Europe program, officially started on November 1^st, 2023, and aims to evaluate the benefits and the potential risks associated with the hydrogen economy. It starts with the analysis of policies and markets to quantify the potential diffusion of hydrogen technologies in the mid-to-long term and the associated emissions of H₂ and other gases (e.g., CH₄, H₂O, NO_X, methanol, NH₃). Using these data, HYDRA will simulate the impacts of the integration of hydrogen in the energy sector using WILIAM, an Integrated Assessment Model accounting for interactions between society, economy, and the environment, which will produce a range of energy, land, and emission scenarios. The FRSGC/UCI Chemical Transport Model will then be used to quantify global and regional impacts on O₃, CH₄, NO_X, VOC, CO, and other oxidants, estimating the uncertainty in the important soil sink of hydrogen. The role of H₂ in influencing stratospheric water vapour, ozone, and nitrous oxide (N₂O) will be determined with the SLIMCAT and UKCA models. The changes in atmospheric composition from these simulations will be used to estimate the effective radiative forcing associated with H₂ emissions and perform future climate projections, using the EC-Earth global climate model. Finally, since hydrogen-air mixes are highly inflammable, HYDRA will develop a new leakage detection/quantification monitoring system to make H₂ technologies safer. The overall benefits and risks associated with a future hydrogen economy will be evaluated from a sustainable perspective, from changes in mean climate conditions to impacts on society and environment. HYDRA is fully committed to finding sustainable solutions for the development of the hydrogen economy, and to proposing mitigation strategies and guidelines for policymakers at the end of the 4-year project.

How to cite: Urgnani, R., Ferreras Alonso, N., Bellucci, A., Wild, O., Panopoulos, K., Santarelli, M., Poinsel, N., and Vicini, I.: Understanding the benefits and risks of the hydrogen economy: the HYDRA project, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7558, https://doi.org/10.5194/egusphere-egu24-7558, 2024.

Hydrogen(H2) is one of the most abundant greenhouse gases in the atmosphere that participates in stratospheric ozone depletion and influences air quality. Using hydrogen as an alternative energy source to meet net-zero carbon emissions by 2050 can increase the risk of Hydrogen Leakage. Excess H2 leaked from a hydrogen economy could travel from the Earth’s surface to the stratosphere, where its oxidation would increase water vapor (H2O) in the upper atmosphere. It also has the potential to modify stratospheric ozone destruction by altering catalytic reactions involving HOx (=OH+HO2) radicals as well as changing stratospheric temperatures. Additional H2 in the air would consume the hydroxyl radical (OH) and lengthen the atmospheric lifetime of methane (CH4), increasing its abundance, whilst the oxidation of both H2 and CH4 generates tropospheric O3. The changes in OH can cause a cascade of climate impacts that includes changes in aerosol clouds. Increases in H2 will increase the concentration of CH4, O3, and H20, resulting in increased radiative forcing. Here, we are using the UK Earth System Model (UKESM) chemistry-climate model to see the effect of indirect radiative forcing arising from increases in H2 in the atmosphere. We have conducted experiments at present and future H2 and CH4 concentrations and analyzed the feedback on O3, aerosol, and stratospheric H2O over the period of 40 years. The highlight of the study is to see the effects of radiative forcing on CH4, O3, and H2o separately . We have seen the effect on one component at a time by switching off the feedback of the other components and also see the effect of radiative forcing as a whole due to an increase in H2 concentration.

How to cite: Chakraborty, T., Thornhill, G., and Collins, B.: Impact of hydrogen on atmospheric composition and climate, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9653, https://doi.org/10.5194/egusphere-egu24-9653, 2024.

When hydrogen is used as an energy carrier, some hydrogen will leak into the atmosphere during production, storage, transport, and end use. Hydrogen itself is not a greenhouse gas, but via chemical reactions in the atmosphere, the leaked hydrogen will affect the atmospheric composition of methane, ozone, and stratospheric water vapor and hence radiation in the atmosphere. A recent multi-model study found the Global Warming Potential over a 100-year time horizon (GWP100) to be 11.6 ±2.8 (one standard deviation). In this study, a chemistry transport model (OsloCTM3) is used to investigate the sensitivity of the calculated GWP100 due to the size of the hydrogen perturbation, the location of the hydrogen perturbation as well as the chemical composition of the background atmosphere.

The hydrogen perturbation of an additional 0.1, 1, 10 and 100 Tg yr^-1 of anthropogenic hydrogen emissions gave GWP values that differed by only 0.4. To test the sensitivity of the location of the perturbation, 1 Tg yr^-1 was added to seven different sites around the world. Perturbations at sites that are further away from dry deposition areas (such as middle of the ocean and in Antarctica) resulted in feedback factor larger than one. The GWP values were enhanced compared to perturbations at sites influenced more by dry deposition where feedback factor was less than one. The difference in GWP100 between the two most extreme sites was 4, less than the width of the ± one standard deviation range from the multi-model GWP100 study.

The hydrogen economy is expected to grow, and in the future, the atmospheric composition might be different than the 2010 atmosphere used to calculate GWP100 in the multi-model study. To check the sensitivity to this the GWP100 is calculated with the perturbations on top of three different 2050 atmospheres using different SSP scenarios. The three different SSPs had different combinations of NOx to CO emission ratios and methane levels that both influence the atmospheric lifetime of hydrogen. The atmospheric lifetime increased in all the scenarios, and in SSP4-3.4 by as much as ~1 year. However, the dominant control on the total lifetime of hydrogen is the soil sink. Thus, future changes to the soil sink should be investigated, with a focus on how it influences the calculated GWP.

How to cite: Skeie, R. B.: Sensitivity of climate effects of hydrogen to leakage size, location, and chemical background, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9851, https://doi.org/10.5194/egusphere-egu24-9851, 2024.

An improved quantification of the soil sink of Hydrogen (H₂) gas is required to understand the environmental implications of a future Hydrogen economy and global atmospheric models. Typically, soil microbes utilise H₂ as an energy source, but we also have evidence that emission of H₂ from soils is also possible via microbial processes. We present new H₂ flux data from several field sites and lab studies in which a variety of soils from around the world have been measured from. These sites include agricultural and forest soils from the UK where we have preliminary data of a longer-term measurement campaign. We have developed flux chamber methodology to establish a best practice for measuring H₂ flux in soils, which is radically different from typical greenhouse gas protocols. We present our work so far on the development of H₂ measurement methodology and on the characterisation of the H₂ soil sink in relation to soil physical & chemical properties, vegetation and climate under controlled environment conditions. We also present observations of spatial and temporal soil H₂ uptake rates from sites across the UK. We highlight the importance of soil aeration and the physical barriers that strongly interfere with H₂ uptake in soils, particularly the influence of high water-filled pore space which should be accounted for in future modelling efforts.

How to cite: Cowan, N., Drewer, J., Roberts, T., Hanlon, M., Di Marco, C., Helfter, C., and Nemitz, E.: Improving quantification and understanding of the global H2 soil sink through field and lab based flux measurements, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10002, https://doi.org/10.5194/egusphere-egu24-10002, 2024.

As result of the global energy transition, it is expected that H₂ emissions are on the rise due to increasing production, transport and usage. Leakage rates might be up to 10% of the total hydrogen production. This will lead to an increase of the global atmospheric hydrogen mole fraction, resulting in the lengthening of the lifetime of in particular methane, enhanced tropospheric ozone production, and increased stratospheric water vapor levels. Because of these effects, H₂ is called an indirect greenhouse gas. We present first results of the use of a high-precision Agilent 8890 GC-system equipped with a Pulsed Discharge Helium Ionization Detector (PDHID) combined with an ‘active’ Aircore and sampling flasks as a tool to detect and quantify industrial H₂ emissions. Our GC-PDHID measures H₂ with a precision <2 ppb and is calibrated and linked to the international NOAA-H2-X1996 hydrogen scale (e Max Planck Institute for Biogeochemistry (MPI-BGC) Jena, Germany). The ‘active’ AirCore is an atmospheric sampling system that consists of a long narrow tube (in the shape of a coil) in which atmospheric air samples are collected using a pump during the sampling experiment, in this way preserving a profile of the trace gas of interest along the measurement trajectory. In this study we focus on potential H₂ emitters in the Groningen province, mainly located at the Delfzijl Chemistry Park bordering the Wadden sea coast. During our field experiments we deployed three different complementary sampling methods. The first method involves the use of an active Aircore system with a sample volume of 4.35 L from a passenger car. This Aircore is filled to an end-pressure of up to 1.6 bar over the course of about 2 hours of sampling resulting in up to 38 discrete H₂ samples on the GC-PDHID. The second method involved the use of an active Aircore system on a UAV with a volume of 3.7 L and filled with a sampling flow of 200 ml min^-1 at atmospheric pressure, allowing for up to 21 discrete H₂ samples. The third sampling technique involved the use of dried and vacuumized 2.3 L glass flasks to collect discrete samples along the measurement trajectory. The glass flasks samples were further analysed by CRDS (Picarro G2401) on mole fractions of CO₂, CH₄, CO, to get additional information on the emission sources co-located with H₂. We found a regional H₂ background of 529 ± 5 ppb in agreement with the European background station observations at Mace Head, Ireland. Our results so far indicate constant undetected industrial H₂ emissions at the Chemistry Park Delfzijl, ranging from enhanced signals of 580 ppb up to 1.5 ppm of H₂ downwind the source area. Based on these results we present first estimates of current industrial H₂-emissions from the Delfzijl Chemistry park. Further work will focus on specific H₂ production and storage infrastructure.

How to cite: Westra, I. M., Scheeren, B. A., van Heuven, S. M. A. C., Kers, B. A. M., and Meijer, H. A. J.: Detection of regional industrial H2 emissions using an active Aircore and a high-precision GC-PDHID system, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10067, https://doi.org/10.5194/egusphere-egu24-10067, 2024.

Context: Increasing use of hydrogen (H₂) across the economy is currently seen as an important strategy for decarbonization of fossil fuel-dependent sectors. Energy scenarios, especially those aiming at net-zero GHG emission targets, project that surplus electricity produced from renewable sources, such as solar and wind, will be converted and stored as H₂ by electrolysis. The use of pure hydrogen would require the replacement or significant modification of some of the infrastructure (e.g. steel pipelines) and end-use appliances (e.g. combustion engines) by H₂-dedicated equipment (e.g. PE/PVC pipelines, fuel cells); in fact, many sectors are already moving towards these solutions. However, hydrogen can also be blended into natural gas and used in the same applications. The combustion of such blends enables reduction of carbon intensity in several sectors without significant technological retrofits. However, hydrogen combustion under lean air conditions leads to higher thermal formation of nitrogen oxides (NOx), when compared to natural gas. The amount depends on the burner type, load and hydrogen blending ratio. While NOx emissions pose a direct risk to human health and act as a precursor to the O₃ and particulate matter, deployment of H₂ would also result in direct leakages to atmosphere and associated climate impacts.

Objective: This study seeks to quantify and evaluate the potential NOx increases in the European Union (EU27) countries due to the combustion of hydrogen blended with natural gas.

Methodology: We use GAINS model framework to conduct this analysis assuming that hydrogen combustion will mostly take place in the buildings, industry (boilers and furnaces) and power generation sectors. The exclusion of the transport sector is justified by the predominant use of hydrogen in fuel cell vehicles, which do not contribute to NOx formation. Since hydrogen blends will be used in the same devices as currently natural gas, existing abatement technologies as well as their adoption rates are kept across all sectors and regions.

Expected Results: We expect the results of this study will allow us a better understanding of hydrogen impacts in terms of pollutant emissions. While the paper asserts that the findings are unlikely to influence the development or viability of future hydrogen economies in Europe, it acknowledges the importance of the analysis in revealing potential emissions trends and identifying local or country-specific trade-offs. The emphasis on existing regulations and emission control strategies in Europe provides context for the limited air quality impacts expected on the overall trajectory of hydrogen adoption. Moreover, these preliminary results could lead to relevant insights regarding expected H₂ fugitive emissions which may impact climate mitigation targets and economical viability. 

How to cite: Brito, T., Höglund-Isaksson, L., Rafaj, P., Sander, R., and Klimont, Z.: Analysis of trade-offs from the use of hydrogen blended with natural gas in the European Union, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10187, https://doi.org/10.5194/egusphere-egu24-10187, 2024.

A shift in our energy production is crucial to the control of global warming. This will occur as fossil fuels are phased out, following legislation created to reach the targets set out in the Paris Agreement. One of the possible sources for a low carbon energy landscape is renewable hydrogen. Whilst hydrogen represents an alternative energy store, it can leak from the system. Understanding the fate of leaked hydrogen is vital to quantify the implications of this energy transition. This study uses the atmospheric version of the United Kingdom Earth System Model to analyse the impact of hydrogen on the atmosphere. The model indicates that increased atmospheric hydrogen leads to an increase in tropospheric ozone concentrations. Ozone is a greenhouse gas and therefore there is an indirect atmospheric warming due to hydrogen emission through ozone. Understanding the relationship between hydrogen and the chemical ozone budget is therefore required to dissect how this warming occurs. We find that hydrogen increases ozone production, governed by the increased flux through the reaction of HO₂ with NO. Future atmospheric nitrogen oxide concentrations are expected to decrease in the coming decades, under most climate scenarios. Understanding the relationship between hydrogen and background NO_x concentrations is therefore crucial in determining the mechanisms of how hydrogen is expected to impact future atmospheres. We use the model to calculate the tropospheric global warming potential of hydrogen and how this is altered by changing background NO_x. We find that this tropospheric GWP will stay relatively constant alongside decreases in ground level anthropogenic NO_x.

How to cite: Bryant, H., Stevenson, D., Heal, M., and Sand, M.: The Impacts of Hydrogen on Tropospheric Ozone and their Modulation by Background NOx, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10918, https://doi.org/10.5194/egusphere-egu24-10918, 2024.

Inflammable air, known today as hydrogen, was first identified and produced in 1766 by the British chemist and physicist Henry Cavendish. Today, hydrogen can be produced by splitting the liquid water molecules. The water electrolysis producing hydrogen can be powered by renewable energy in the case of "green" hydrogen. Hydrogen is also produced from fossil fuels by steam reforming of methane in natural gas in conjunction with carbon sequestration in the case of "blue" hydrogen, or without carbon sequestration in the case of "grey" hydrogen. The use of hydrogen enables energy conversion and storage, and can provide a way to decarbonize sectors of the economy where decarbonization has no alternative or is hard to reach, such as long-distance transport by truck, train or airplane, heavy industries, or for domestic use in mixture with natural gas. Hydrogen has no direct greenhouse effect but is an indirect climate gas which induces perturbations of atmospheric methane, ozone and water vapour, three powerful greenhouse gases. The budget of atmospheric molecular hydrogen will be presented and the main sources and sinks will be briefly discussed. Based on the results of state-of-the-art global numerical climate and chemistry models, we derive various indicators intended to quantify the climate impact of hydrogen and in particular derive its Global Warming Potential (GWP).

All the scenarios considered in this study for a future transition towards a hydrogen economy in Europe or in the world clearly suggest that a "green" hydrogen economy is beneficial in terms of CO₂ emissions mitigation for the relevant time horizons and leakage rates considered. In contrast, the results suggest that carbon dioxide (CO₂) and methane (CH₄) emissions associated with the production and transport of "blue" (and "grey") hydrogen reduce the climate benefit of such a transition and even introduce a climate penalty in the event of a very high leakage rate or strong penetration of "blue" hydrogen on the market. Various assumptions will be illustrated for future “blue” hydrogen production carbon intensity. Reducing the leakage rate of H₂ (and CH₄ in the case of "blue" hydrogen production) and increasing the "green" hydrogen production sector appear to be the key levers towards maximum mitigation of CO₂ emissions from a large-scale structural transition to a hydrogen economy.

In addition, in the specific case of aviation, the use of liquid hydrogen powered aircraft induces additional climate forcings from water vapour emissions in the upper atmosphere and from impact on contrail formation. In the case of an hydrogen powered fleet, the forcings from NOx and from contrails are still subject to large uncertainties. These effects will be illustrated based on various assumptions for future aircraft using hydrogen fuel.

How to cite: Hauglustaine, D.: The climate impact of a future hydrogen economy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11016, https://doi.org/10.5194/egusphere-egu24-11016, 2024.

Hydrogen and ammonia fuels are being explored as cleaner and sustainable energy alternatives to fossil fuels, due to their potential for decarbonization. The production of renewable energy-based hydrogen converted into green ammonia offers a more efficient solution for storing and transporting energy than gaseous hydrogen. However, both ammonia and hydrogen can indirectly lead to air pollution.

Ammonia, if leaking to the atmosphere, plays a role in forming secondary aerosols, generating particles like ammonium nitrate that add to fine particulate matter (particulate matter with diameter <2.5 micrometers; PM2.5). Additionally, the production of oxides of nitrogen (NO_X) gases during ammonia combustion contributes to tropospheric ozone formation and can influence aerosol abundance (as NO_X may lead to less aerosols and not necessarily more). Hydrogen, if leaked to the atmosphere, will impact tropospheric ozone and possible aerosols through a complex chain of chemical reactions.

Our research aims to assess the potential air quality effects of shifting to a hydrogen and ammonia-based economy.

Using simulations from the three-dimensional global chemical transport model (OsloCTM3), we are investigating the impacts of hydrogen and ammonia on key air quality parameters, with a specific focus on surface concentrations of ozone and PM2.5.

We will attempt to assess the benefits of this energy transition in relation to the reduction of atmospheric pollutants associated with fossil fuels. In the case of ammonia, we will compare air pollution impacts across different emission sectors. Future work will involve the analysis of chemistry-climate model simulations.

How to cite: Jouan, C., Hodneborg, Ø., and Skeie, R.: Impact of Hydrogen and Ammonia on Surface Air Pollution., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12262, https://doi.org/10.5194/egusphere-egu24-12262, 2024.

Accurate quantification of leaks associated with hydrogen transport and storage infrastructure is vital to evaluate the environmental benefit associated with the transition from fossil fuels to hydrogen as an energy source. Understanding the locations and magnitudes of leaks is critical in efforts to mitigate the indirect climate impact of transitioning to a hydrogen economy. Quantification of hydrogen leaks requires a field-deployable, fast, sensitive measurement technology which, until recently, has not existed. We have developed a novel inlet system which couples to an Aerodyne tunable infrared laser direct absorption spectrometer (TILDAS) to measure hydrogen with <5 ppb precision and <5 second time response. Laboratory-based instrument performance results and data from recent mobile measurements will be presented.

How to cite: Lunny, E., Wehr, R., Roscioli, J., Daube, C., Shorter, J., Sun, T., Long, W., Momeni, A., Albertson, J., Herndon, S., and Nelson, D.: Quantifying leaks with a field-deployable, fast, sensitive hydrogen instrument, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14242, https://doi.org/10.5194/egusphere-egu24-14242, 2024.

Using hydrogen as an alternate fuel source could lead to lower carbon emissions if sourced from renewable energies. However, it can act as an indirect greenhouse gas by extending the lifetime of methane and causing stratospheric water vapour to increase. The global production and loss of hydrogen in the atmosphere are important in order to quantify its lifetime and, by extension, its global warming potential. The main sinks for hydrogen are loss through chemical reactions with OH and biological soil uptake, the latter of which accounts for approximately 80% loss and, on average, has an error range of +/-40%. Due to the wide potential range of deposition velocities and its large global impact on hydrogen, this introduces a major uncertainty to the overall hydrogen budget.

Previously in the UK Chemistry and Aerosol model (UKCA), the soil uptake of hydrogen was fixed temporally and depended on land type, following the scheme by Sanderson et al. (2003). We have implemented the deposition scheme from Paulot et al. (2021) into UKCA in order to better represent the uptake of hydrogen. A wide range of soil parameters are used in the updated scheme: soil moisture, temperature, snow depth, soil carbon content, soil type, and soil saturation content, which allow for a more diverse and dynamic range of deposition velocities. These results from UKCA are evaluated against previous global hydrogen budgets and verified against hydrogen observations from the National Oceanic and Atmospheric Administration.

The calculation of hydrogen deposition velocity onto soil is independent of atmospheric hydrogen, and, as a result, can be calculated offline. We use data from CMIP6 simulations as inputs to calculate a range of global hydrogen deposition velocities across multiple future projections using a range of different deposition models. The different uncertainties associated with models (hydrogen deposition and climate models) natural variation, and future scenarios can be isolated. Fluctuations in deposition and variation through time can be analysed to assess the which factors have the greatest contribution to the hydrogen deposition velocity uncertainty.

How to cite: Brown, M., Archibald, A., Abraham, L., Warwick, N., and Griffiths, P.: Modelling the Global Uncertainty of Hydrogen Deposition, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16477, https://doi.org/10.5194/egusphere-egu24-16477, 2024.

Aviation accounts for approximately 5% of the current anthropogenic climate impact. Up to two thirds of the warming generated by airplanes is attributed to non-CO₂ effects with contrail cirrus as the largest contributor. Hydrogen as aviation fuel promises zero carbon emission but the non-CO₂ effects of this new fuel are poorly known.

In this study we investigate the generation of contrail cirrus from hydrogen combustion using a modified version of the Contrail Cirrus Prediction model (CoCip). In the absence of soot-emissions ice particles in hydrogen contrail are assumed to form on entrained aerosols, ultrafine volatile particles and lubrication oil. The calculation of the number of ice particles formed on entrained aerosols is approximated by previously published simulation results and theory.  Ultrafine volatile particles and lubrication oil both activate into water droplets at lower temperatures than soot and aerosols due to the Kelvin effect (small radius) and hydrophobicity respectively and are implemented using theory and published experimental results.

Using hydrogen fuel contrails can, according to the Schmidt-Appleman criteria, form at lower altitudes than with jet fuel due to the increase in water vapor in the exhaust. Despite this our preliminary results show an overall decrease in both warming and cooling contrails for hydrogen compared to standard jet fuel. We do find that hydrogen contrails can generate more radiative forcing than jet contrails at very low temperatures mainly due to the activation of lubrication oil in combination with the larger amount of water vapor. For the bulk of flights however, hydrogen fuel leads to either equal or less contrail radiative forcing than jet fuel even with reduced soot-emissions in line with lean-burn engines.   

How to cite: Pettersson, S. and Johansson, D.: Climate effects of contrail cirrus for aircraft with hydrogen combustion   , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16712, https://doi.org/10.5194/egusphere-egu24-16712, 2024.

Hydrogen fuel, a green transition option and a cleaner alternative to fossil fuels, has an indirect greenhouse impact through atmospheric reactions of “leaked” hydrogen. Sand et al., 2023 used six different chemistry-transport models (CTM) to estimate a Global Warming Potential over a 100-year time horizon (GWP-100) for hydrogen of 11.6 ± 2.8, in range with similar studies. In this study, we extend those analyses by investigating the atmospheric production and loss terms of hydrogen in the CTMs. Specifically, we compare formaldehyde (HCHO) and the hydroxyl radical (OH) concentrations. Then we develop a box model that can be used for quickly evaluating the impact of the different sources and sinks on atmospheric concentration and isotopic composition of H₂ from a global perspective.

Atmospheric production of hydrogen through photo-oxidation of methane and volatile organic compounds represents roughly 60% of the total production. To compare the atmospheric production in the models, we evaluate HCHO (produced during photo-oxidation). A preliminary comparison between the global mean model-derived tropospheric HCHO and TROPOMI-derived HCHO suggests that all models other than WACCM perform reasonably well. Generally, models tend to overestimate HCHO values over land and underestimate HCHO concentrations over the oceans. WACCM has very low HCHO values compared to TROPOMI and the other models.

The two primary removal mechanisms are soil uptake (65-85%), and atmospheric oxidation by hydroxyl radical (OH). Among the models, OsloCTM3 and WACCM have higher OH concentrations compared to GFDL, INCA and UKCA. Direct measurements of atmospheric OH concentrations are lacking due to the short lifetime of the OH radical. Therefore, we used CO and NO₂ concentrations as a proxy to evaluate the models. Compared to satellite values (TROPOMI for NO2 and MOPPIT for CO), models seem to generally overestimate NO₂ and underestimate CO. These results are discussed within the context of the OH radical and atmospheric lifetime of H₂.

Then we present a simple box model that is developed using CTM results for studying the atmospheric budget of H₂. Reconstructions of hydrogen concentrations using ice-core records from the South Pole over the last 150 years show an increase in H₂ concentration of ~200ppb, likely due to increased methane oxidation and anthropogenic emissions. We use time-varying emissions in our box model to replicate this time evolution since the pre-industrial period.

The box model also contains a framework for studying hydrogen isotopic composition. Each of the sources and removal processes of H₂ have distinct isotopic signatures. This allows for the evaluation of concurrent changes in atmospheric concentrations and hydrogen isotopic compositions for each source/sink contribution, leading to a more robust evaluation of the hydrogen budget in the atmosphere.

How to cite: Krishnan, S.: Atmospheric hydrogen budget: an evaluation using chemistry-transport models and a box model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16977, https://doi.org/10.5194/egusphere-egu24-16977, 2024.

Increased fugitive hydrogen in the stratosphere can promote chemical reactions that result in increased lifetimes and abundances of gases that have a harmful climate impact. It is therefore crucial to understand the significance of this effect, and thereon identify and mitigate potential leakage pathways within future hydrogen energy systems. Repurposing the existing high-pressure National Transmission System and low pressure local gas distribution networks for pure or blended hydrogen delivery throughout the UK, is a solution favoured by existing gas network operators. It minimises the necessary replacement of pipeline infrastructure by re-use of £30bn of already installed welded polythene pipe network and compatible assets, which will decrease associated transport costs. However, gaseous hydrogen can compromise mechanical properties of carbon steels, posing integrity concerns for pipelines and other network components. Considerable work has investigated the extent to which material integrity could affect the repurposing potential of existing infrastructure. By contrast, this study aims to quantify the ranges of anticipated increase in atmospheric hydrogen release upon conversion of existing UK gas networks for hydrogen delivery. Based on existing network architectures, provided by UK network operators, we identify the most likely locations for leakage within UK pipeline networks and present a static model to estimate potential fugitive hydrogen. Sensitivity analyses have been undertaken to assess the impact of emissions mitigation strategies, including polythene renewal in the Iron Mains Replacement Programme and replacement of wet compressor seals. Consequently, we can consider both physical leakage at joints and equipment, and permeation losses through pipe walls from natural gas leakage data. Our findings indicate that, while significant, the climate implications of determined theoretical rates of potential hydrogen leakage without mitigation are between 6.5 and 14 times less than those associated with current natural gas transport, based on respective GWP100s. It should be noted that we have considered only the potential emissions associated with pipeline transport, and have thus ignored the additional impact of embedded supply chain emissions.

We further propose a geospatial distribution of these potential hydrogen emissions across the UK network. The dataset could serve as a crucial input for future climate modelling to assess the impact of emission location dependency on hydrogen’s global warming potential and quantify the benefits of mitigating leakage in identified “hotspots”. 

How to cite: Peecock, A., Schewe, L., and Haszeldine, S.: Fugitive hydrogen emissions from a converted national UK network of methane pipelines – stratospheric climate impacts, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19183, https://doi.org/10.5194/egusphere-egu24-19183, 2024.

Many global climate and Earth system models that participated in CMIP6 did not include fully interactive chemistry mechanisms mainly due to the large associated computational cost of these schemes. A number of studies have recently highlighted the potential importance of enhanced aerosol-chemistry-climate coupling and associated feedbacks for the anthropogenic effective radiative forcing (ERF) of a number of key climate forcing agents such as aerosols (Thornhill et al., 2021), methane (O’Connor et al., 2022) and ozone. The different levels of complexity in both aerosol and chemistry schemes in CMIP6 models has been highlighted as a leading contributor to the large inter-model diversity in the ERF of aerosols and trace gas species (Thornhill et al., 2021). To this end, as part of the EU Horizon project, ESM2025, advanced stratospheric-tropospheric chemistry schemes have been developed and implemented in 2 ESMs, CNRM-ESM and NorESM2, for the first time. Dedicated experiments have been conducted to determine the pre-industrial (1850) to present-day (2014) ERF with these updated models and the UKESM1.1 model, to assess the impact of fully interactive chemistry on the ERF of key forcing agents. In UKESM1.1, which already includes interactive chemistry, the interactive chemistry scheme is switched off and run with a much-simplified aerosol-chemistry mechanism driven by prescribed oxidant fields. We argue the improved realism of representing these aerosol-chemistry-climate interactions is essential for improved cross-model consensus on the magnitude of anthropogenic ERFs of aerosol and key trace gas species.

References:

Thornhill et al., Effective radiative forcing from emissions of reactive gases and aerosols – a multi-model comparison, Atmos. Chem. Phys., 21, 853–874, https://doi.org/10.5194/acp-21-853-2021, 2021.

O’Connor et al., Apportionment of the pre-industrial to present-day climate forcing by methane using UKESM1: The role of the cloud radiative effect. Journal of Advances in Modeling Earth Systems, 14, e2022MS002991. https://doi.org/10.1029/2022MS002991, 2022.

How to cite: Mulcahy, J., Cussac, M., Olivie, D., Nabat, P., Michou, M., and Lathiere, J.: Quantifying the role of interactive chemistry on the anthropogenic effective radiative forcing in Earth System Models, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20693, https://doi.org/10.5194/egusphere-egu24-20693, 2024.

Abstract: Agrobiodiversity, a key principle of agroecology, encompasses crop diversification, offering resilience to climate variability (Ronnie Vernooy, 2022). Increasing crop species diversity within a region could improve agricultural sustainability, but knowledge of the spatiotemporal variation of crop species diversity and how this is related to climatic conditions is limited (Sjulgård, H., et al., 2022). Higher crop diversity may alleviate the effects of heat stress (Degani et al., 2019, Marini et al., 2020) and drought (Bowles et al., 2020, Marini et al., 2020) on crop yields. Therefore, crop diversity will play a crucial role in the functioning of agroecosystems under climate change (Sjulgård, H., et al., 2022). Hence, this study aims to investigate the relation between the spatiotemporal pattern of crop diversity and changing climatic conditions at the district level in India by building relationship between crop diversification and climatic variables. Crop species diversity was estimated using the Shannon Index. Advanced statistical analysis was used to understand the relationship between climatic variables and crop diversity. The outcome will also help the policymaker, researchers, and field practitioners in designing climate-resilient agricultural practices following the principles of agroecology.

Keywords:

Crop diversification, Shannon Index, Climate variables, Risk map, Agrobiodiversity, Agroecology, India.

Figure 1: Schematic representation of the proposed work

How to cite: Kumari, C., Shukla, R., and Gleixner, S.: Understanding spatio-temporal pattern of crop diversification for India, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1070, https://doi.org/10.5194/egusphere-egu24-1070, 2024.

Maize cultivation significantly contributes to global food security and sustains human livelihoods. Efficient early-season maize mapping is pivotal for forecasting production and informed pre-harvest decisions. Existing approaches rely on prolonged phenological data or available crop labels, limiting their applicability in areas lacking comprehensive data. Thus, an automated, dynamic, and accurate maize identification method for the early growing season is crucial. This study explores spectral bands to distinguish maize early in terms of water content and chlorophyll levels. A novel composite index for dynamic maize identification independent of labels was proposed. Utilizing this index with a multi-temporal Gaussian Mixture Model facilitated early-season maize mapping and identification. Assessments across diverse global regions revealed the method's robustness, consistently achieving 90% accuracy and F1-score. NDCI outperformed other indices, enhancing F1-score by up to 30%. NDCI-mGMM accurately generated maize maps two months pre-harvest, promising an F1 score of at least 77%. Operating autonomously from labels, this framework offers swift and precise maize identification in data-deficient regions, revolutionizing global food security and trade forecasts.

How to cite: Gao, Y., Pan, Y., Ren, S., and Zhao, C.: A novel composite Index for early-season maize mapping, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1392, https://doi.org/10.5194/egusphere-egu24-1392, 2024.