As underlined by the IPCC and IPBES, climate change and biodiversity loss are deeply interconnected and must be addressed jointly. This session therefore focuses on how NbS can serve as adaptation strategies to climate change, while simultaneously preserving or restoring biodiversity. Considering various ecosystems (marine and coastal, urban, cropland, mountainous, forest, rivers…), NbS as climate change adaptation solutions includes the adaptation to: sea level rise (flooding and erosion), changes of the water regime (floods, droughts, water quality and availability), rise in temperatures (heat waves, forest fires, drought, energy consumption), plant stress and increase of pests (variation of yields, forest dieback), to minimize their associated social and economic negative impacts.
Therefore, this session aims to promote discussion integrating multiple disciplines related to ecosystem restoration, preservation and management, to put forward the complexity that is often hidden by simplifying hypotheses and approaches (sector-based silo approach, homogeneity of environments...).
Specific topics of interest are the followings:
- Complexity: nature of ecosystems and risk of oversimplification, interconnection between NbS and complementary areas, consideration of uncertainties
- Scales: spatial scales with the integration of NbS in their environment, and temporal scales considering sustainability over time, variability of bio-physical processes and climate change effects
- Ecosystem services: bio-geophysical processes, spatial shift between the location of NbS and the beneficiaries one, modification under climate change (tipping point), co-benefits or negative effects
- Assessment and indicators: measurement and modelling protocols, capacity to measure the complexity, resilience and stability of NbS
- Co-development with stakeholders, engaging civil society, and integrating NBS into education, aligned with IAHS Helping Decade objectives
Orals: Thu, 7 May, 10:45–12:30 | Room 2.24
The recent adoption of the EU Nature Restoration Law sets ambitious targets for reversing biodiversity loss and enhancing ecosystem resilience, yet its implementation faces critical knowledge gaps. One key challenge concerns the potential of Nature-based Solutions (NbS) to deliver multiple benefits for human well-being beyond ecological restoration, particularly in the context of climate change adaptation and mitigation. Addressing this gap, the EVESNAT project (www.eurac.edu/evesnat) explores how NbS can support both biodiversity conservation and ecosystem service provision in Alpine social-ecological systems. Focusing on three distinct case study sites across the European Alps, the project employs a participatory approach to co-develop spatially explicit NbS scenarios tailored to local contexts. These scenarios aim to address pressing issues identified by stakeholders, including biodiversity enhancement, climate change mitigation, and strengthening community resilience and autonomy. To evaluate NbS effectiveness, EVESNAT applies an integrative framework that quantifies provisioning (e.g., food, timber, water), regulating (e.g., climate control, hazard mitigation), and cultural services (e.g., recreation, aesthetics), while considering spatial relationships between NbS locations and beneficiaries. The assessment incorporates robust indicators across spatial and temporal scales, accounting for variability in biophysical processes and long-term sustainability to capture co-benefits of NbS. Furthermore, the project emphasizes co-development with stakeholders and engagement of civil society. By analyzing synergies and trade-offs among ecosystem services and biodiversity co-benefits, EVESNAT provides empirical evidence on how NbS can optimize ecological and social outcomes under restoration policies and changing environmental conditions. The findings will offer actionable insights for adaptive governance and sustainable landscape management, bridging science and practice to enhance resilience in mountain regions under changing environmental and societal pressures.
How to cite: Schirpke, U., Gonzalez Ramil, A., Von Maltzahn, M., Menestrina, L., Brocco, S., Leitinger, G., Tappeiner, U., Grêt-Regamey, A., Probst, Y., Bé, M., Chidi Uche, L., Déléglise, H., and Palomo, I.: Nature-based solutions in Alpine regions: Co-benefits for biodiversity and ecosystem services, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3991, https://doi.org/10.5194/egusphere-egu26-3991, 2026.
The combined pressure of climate change and an increasing demand for settlement space poses an escalating threat to critical infrastructure, human lives, and livelihoods in alpine regions. While conventional grey engineering is commonly deployed to provide immediate safety, its static nature often fails to adapt to shifting environmental risks and requires cost-intensive maintenance. Nature-based Solutions (NbS) offer a sustainable alternative, yet their deployment is hindered by a lack of quantitative links between physical hazardous processes and the long-term performance of individual solutions. To bridge this gap, this study introduces a three-layered framework to assess the protective capacity throughout the service-life of a NbS on a functional, quantitative, and temporal level.
The methodology categorizes 74 NbS types against 29 distinct natural hazards and identifies six functional clusters using Principal Component Analysis. These clusters reveal strategic trends ranging from localized bioengineering solutions (e.g., vegetated cribwalls, live fascines) to landscape-level watershed management approaches (e.g., afforestation, wetland restoration). A specialized Mitigation Score identified "hotspots," such as erosion control, where NbS are highly effective, while highlighting critical "gaps" in complex flood hazards where hybrid grey-green infrastructure may be necessary. The Mitigation Score varied significantly across hazard classes. Erosion processes (e.g., sheet, rill, and gully) achieved the highest scores (1.90), supported by a high density of effective NbS interventions (21–33 types). Conversely, fluvial and pluvial flooding yielded moderate scores (1.64–1.66), while coastal and impact floods showed the lowest mitigation potential (1.00–1.42) due to a more limited range of viable NbS options.
The framework’s core innovation is the use of temporal hazard profiles to track intervention utility across four phases: reduced predisposition, trigger prevention, ongoing process mitigation, and post-event resilience. These profiles reveal distinct patterns and visualises the temporally variable effectiveness for each individual natural hazard.
Unlike grey infrastructures, which reach their maximum protection capacity immediately after construction, the effectiveness of NbS is not linear and is intrinsically linked to biological maturation, which may take decades. This framework provides practitioners and policymakers with a robust, evidence-based guide for the strategic and lifecycle-aware deployment of NbS, bridging the gap between theory and engineering practice to ensure the long-term resilience of alpine infrastructures and livelihoods.
Acknowledgments: Funding for this research has been provided by the European Union’s Horizon Europe Programme in the framework of the NATURE-DEMO project under Grant Agreement no. 101157448.
How to cite: Kuschel, E., Obriejetan, M., Kuzmanić, T., Mikoš, M., Seifert, L., Conevski, S., Wirth, M., Canga, E., Fernandes, S., Hübl, J., and Stangl, R.: Dynamic Protective Capacity of Nature Based Solutions in Alpine Infrastructure Protection Strategies, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12578, https://doi.org/10.5194/egusphere-egu26-12578, 2026.
Anthropogenic climate change at the global scale is causing rapid shifts in weather patterns and hydrological regimes regionally and locally. As the magnitude, frequency and intensity of extreme weather events are getting more severe, this has direct impacts on humans, hydrology, infrastructure, and ecosystems. Additionally, the cumulative and compound impacts of climate change on hydrological systems over time poses added risks to socio-economic and socio-ecological structures due to integrative and synergistic effects. These effects, and their underlying mechanisms, are more complex than those of single extreme weather events and the severity of the impacts depend both on the combination of hazards and on how the surrounding human-water system reacts, adapts and evolves with changing hydrological conditions. Nature-based solutions (NbS), such as wetland conservation and restoration, re-meandering of waterways and reforestation are examples of adaptation measures that are gaining increasing attention due to their potential to buffer hydrological extremes whilst also providing ecological and human well-being benefits.
Understanding these cumulative impacts of climate change, and the role of NbS in supporting multifunctional adaptation, require holistic models that account for the co-evolution of social, ecological and hydrological systems. System dynamics (SD) is a modeling paradigm with a long history in integrated systems modeling that is well suited for this purpose due to its explicit focus on endogenous representation of complex feedback processes.
In this research, we apply SD to study the cumulative impacts of climate change in the Riviere du Nord watershed, Quebec, Canada. We present a scalable and modular hydrological simulation model with a daily timestep. Down-scaled climate scenarios from CanDCS-M6 are used as forcing data to study impacts of future hydrological flows and water levels on local communities. The hydrological model is designed to be seamlessly integrated with additional social and ecological modules to capture cascading effects on long-term human well-being and biodiversity indicators, supporting the design of robust multifunctional nature-based climate adaptation strategies.
How to cite: Nicolaidis Lindqvist, A., Alizadeh, M. R., and Adamowski, J.: Integrated modeling of climate risks and Nature-based Solutions in the Riviere du Nord watershed, Quebec, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9008, https://doi.org/10.5194/egusphere-egu26-9008, 2026.
Environment and Climate Change Canada is implementing the ten-year Nature Smart Climate Solutions Fund (NSCSF) to mitigate net greenhouse gas emissions while providing multiple co-benefits to biodiversity and human well-being. Accounting for these co-benefits involves the need to characterize ecosystem service flows across a broad range of sites within the Canadian landscape. To support this objective, a standardised approach has been developed to assess water-focused ecosystem services at NSCS pilot sites, across three ecozones, and ranging in size from 12.5 to 635 ha. Four of the pilot sites are restoration targets, with a degraded landcover base-case scenario, and four are securement targets, with a natural land cover base-case scenario. The national scale Canada1Water (C1W) hydrogeological data and modelling framework was adopted, thus ensuring consistent data fidelity and model structure across sites. The fully integrated hydrologic modelling was implemented in HydroGeoSphere and is an unique solution for ecosystem services assessment, because groundwater, soil moisture, and surface water (ponds, wetlands, and streams) are dynamically coupled and simulated under transient climatology that includes both flood and drought conditions. Recognizing that NSCSF site sizes vary considerably, the model construction methodology also ensures consistent spatial resolution to facilitate comparison of land cover efficacy towards ecosystems services between sites. Outputs from the modelling are used to assess landcover influences on stream/river flow rate, cumulative discharge; wetland water storage; groundwater recharge, discharge, and storage; soil moisture; and cumulative evaporation and transpiration. The simulated hydrologic influences are then normalized (0 to 2 for the restoration sites and 0 to -2 for the securement sites) and plotted on a cumulative-step plot that translates hydrologic differences into visualized differences in water-focused ecosystem services. This approach, leveraging C1W for its ability to facilitate national scale hydrologic analysis, could form the basis of a highly efficient water-focused ecosystems services assessment at all NSCSF sites. Subsequent to the eight pilot case studies, an alternative quasi 2-dimensional column modelling solution is being implemented. This approach removes the model mesh development overhead and permits user selection within a web-based or GIS environment. While lacking some of the advantages of a full three-dimensional solution, it provides the advantage and flexibility of being deployed across thousands of sites without the need for apriori knowledge of site locations.
How to cite: Russell, H. A. J., Frey, S. K., Preston, S., Lapen, D., and Kessel, E.: Characterizing groundwater and surface water contribution to ecosystem services: A Canadian national-scale framework, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15853, https://doi.org/10.5194/egusphere-egu26-15853, 2026.
Nature-based Solutions (NbS) are increasingly promoted as key strategies for climate change adaptation, particularly in drought-prone regions where water scarcity, ecosystem degradation and socio-economic vulnerabilities interact across spatial and institutional scales. As emphasized by IPCC and IPBES, effective adaptation has to jointly address climate risks and biodiversity loss, while explicitly accounting for governance structures, equity and different vulnerability. However, current NbS assessments often focus on biophysical performance, overlooking cross-scale governance dynamics and the distribution of ecosystem services benefits and costs.
This contribution presents a cross-scale ecosystem services modelling framework developed within the NBS4Drought project (Horizon Europe - Grant No. 101181351) to support the assessment of NbS for drought adaptation in complex social–ecological systems. Grounded in ecosystem services research and social–ecological systems theory, the framework conceptualizes NbS as embedded interventions whose outcomes depend on interactions between ecological processes, social actors and decision-making structures operating across scales.
The proposed modelling framework integrates four interconnected analytical components: (i) identification of drought-relevant ecosystems and associated provisioning, regulating and cultural ecosystem services; (ii) mapping of social actors involved in NbS use, management and regulation across spatial and institutional scales; (iii) assessment of actors’ dependence on ecosystem services and their capacity to influence NbS-related decision-making; and (iv) analysis of cross-scale interactions, power asymmetries and governance mismatches shaping NbS effectiveness. This structure directly responds to IPCC and IPBES calls to operationalize equity, enabling the evaluation of both procedural equity (who participates in decisions) and distributive equity (who benefits from NbS outcomes), as well as actors’ vulnerability to drought under changing climatic conditions.
To explicitly capture system complexity, feedback mechanisms and non-linear dynamics, the framework is operationalized through participatory System Dynamics (SD) modelling, used to jointly explore and structure stakeholders’ understanding of how drought processes, NbS interventions and ecosystem services interact over time. SD modelling enables the exploration of cross-scale feedbacks between ecological processes, management decisions and governance structures, addressing key limitations highlighted in recent global assessments (e.g., static representations, sectoral silos and limited consideration of feedbacks and non-linear responses).
By linking these dynamic representations to ecosystem services and governance analysis, the framework supports the identification of scale mismatches, co-benefits and trade-offs between drought adaptation, biodiversity conservation and human well-being, including potential spatial disconnections between ecosystem service production and beneficiaries under climate change.
The proposed modelling framework aims to provide a transferable analytical basis to support more robust, inclusive and context-sensitive NbS pathways for drought adaptation.
How to cite: Coletta, V. R., Selicato, L., Pagano, A., and Giordano, R.: A cross-scale ecosystem services framework to assess Nature-based Solutions for drought adaptation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22157, https://doi.org/10.5194/egusphere-egu26-22157, 2026.
Arid and semi-arid regions are among the most vulnerable to climate change, facing the combined pressures of chronic water scarcity, rising temperatures, and an increasing frequency of extreme rainfall events. Climate change is intensifying hydrological variability in these regions, amplifying prolonged droughts while also increasing the occurrence of short, high-intensity storms that generate flash floods, particularly in urban areas. Addressing these compound risks requires integrated adaptation strategies capable of simultaneously managing water scarcity, flood risk, and heat stress. In this context, Nature-Based Solutions (NbS) are increasingly recognized as a promising approach, offering multifunctional benefits that extend beyond the single-purpose performance of conventional grey infrastructure.
This contribution presents a systematic review of NbS applications based on the analysis of 89 peer-reviewed case studies. The review assesses geographical distribution, typologies, targeted societal challenges, structural and vegetation characteristics, and water management strategies. The focus is placed on the capacity of NbS to generate synergies for climate change adaptation by jointly addressing drought mitigation, flood risk reduction, and microclimate regulation, while enhancing ecosystem services and long-term urban and territorial resilience.
Quantitative evidence from the review highlights the dominance of water-related adaptation objectives. Across all cases, 39% of NbS primarily target drought mitigation, increasing to 61% when combined objectives such as flood mitigation and water security are considered. Green roofs represent the most frequently implemented NbS, accounting for 33% of interventions in arid regions and 24% in semi-arid regions. Rain gardens follow (12% in arid and 16% in semi-arid contexts), while detention and urban parks each account for approximately 10% of cases in arid regions. In semi-arid regions, detention tanks are particularly relevant, representing 21% of applications, reflecting a stronger emphasis on flood management. Importantly, NbS addressing both drought and flood risks are common: green roofs appear in 40% of these multi-hazard cases, while rain gardens and detention tanks each account for approximately 20%, underlining their synergistic role in regulating hydrological extremes.
From an ecosystem services perspective, regulation and maintenance services dominate, particularly runoff attenuation, evapotranspiration-driven cooling, and soil moisture enhancement. Vegetation selection is explicitly discussed in 46 out of 70 vegetated NbS cases, with drought-resistant and native species prevailing, especially in arid climates. Regarding water supply, 88 studies include irrigation systems; when specified, 56 rely on rainwater, 11 on greywater, and only 2 on desalinated water, highlighting both the centrality of water reuse and the limitations of conventional sources in dry regions.
The findings confirm that NbS deliver their highest adaptive value when implemented as integrated systems rather than isolated measures. By combining storage, infiltration, evapotranspiration, and reuse functions, NbS can buffer hydrological variability while providing co-benefits for urban cooling, biodiversity, and livability. However, their effectiveness depends on climate-adapted design, appropriate vegetation choice, and institutional frameworks that recognize NbS as legitimate components of climate adaptation strategies.
Overall, this review demonstrates that NbS offer measurable and scalable synergies for climate change adaptation in arid and semi-arid regions. The quantitative evidence provided supports their integration into planning and policy frameworks as cost-effective, multifunctional solutions capable of addressing multiple climate risks simultaneously.
How to cite: Marchioni, M., Cristiano, E., Chiarelli, D. D., and Padoan, F.: Nature-Based Solutions for Integrated Climate Adaptation in Arid and Semi-Arid Regions: A Systematic Review, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20337, https://doi.org/10.5194/egusphere-egu26-20337, 2026.
Shaded coffee production in agroforestry systems, as opposed to full sun production, is a nature-based solution (NbS) that helps maintain soil water balance and reduce heat exposure of coffee plants. It is part of a range of NbS co-produced with stakeholders in the project SAbERES, which aims at supporting climate change adaptation for small-scale producers in Mexico. For this coffee production system, we analyze current and estimate future yields of small coffee growers in Mexico by employing a process-based coffee growth model CAF2014 adapted for geo-spatial applications and named CAF2014-Rhaobi. A range of climate projections reflecting the SSP5-8.5 scenario until 2100 is taken from an ensemble of five CMIP6 climate models to bracket climate ensemble response.
As NbS in agriculture are typically based on complex ecological interactions, a first crucial step in their modelling is the analysis of model sensitivity to its key inputs and validation of its ability to reflect reported yields. Particular attention was paid to the model’s sensitivity to adjustments in plot management such as shade trees pruning, projected changes in precipitation, hydrological soil parameters, and implications of using different soil datasets. The modeling of smallholders’ representative management was carried out based on parametrizations derived from literature. This informed key parameters of fertilizer application including nitrogen supply by litter from N-fixing shade trees and shading cover management, i.e., tree thinning and pruning frequency. Besides the quantification of crop yield changes per se, the project will analyze economic implications based on the spatial distribution of coffee yields and prices as reported by the Mexican Agri-Food and Fisheries Information Service (SIAP).
The modelled historical coffee yields are found to be in good agreement with the SIAP reported numbers, while there is a clear overestimation in the south-western part of the coffee producing region of Mexico. This is explained by a range of modeling assumptions and simplifications rendering the model less representative for this region. While shade trees provide some resilience, average drop in shaded coffee yields under present management estimated for the majority of the agro-environmentally diverse coffee producing regions in Mexico across all climate projections is about 25% at the end of the century. There are only few regions that are able to maintain their historical yields. These preliminary results underpin that shade trees as a single NbS do not suffice for climate adaptation in the long run under high warming conditions but will need to be combined with other measures. Future work may include refinement of modeling assumptions based on stakeholders input and analysis of economic implications driven by yield change estimates.
How to cite: Folberth, C., Khabarov, N., Skalsky, R., Gonzalez-Abraham, C. E., and Javalera Rincon, V.: Modeling Climate Impacts on Agroforestry-Based Coffee Production of Small Growers in Mexico, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5717, https://doi.org/10.5194/egusphere-egu26-5717, 2026.
Mediterranean agro-silvo-pastoral ecosystems (MAEs) are increasingly affected by water scarcity, rising temperatures, drought, and land-use change, all of which reduce water availability and system resilience. These combined pressures threaten long-term ecological and economic sustainability by contributing to declining profitability, land abandonment, and land degradation. Collectively, these processes reduce ecosystem functions and the capacity for carbon sequestration.
The Horizon Europe DRYAD project ("Demonstration and modelling of nature-based solutions to enhance the resilience of Mediterranean agro-silvo-pastoral ecosystems and landscapes") advances current knowledge by designing and implementing evidence-based, scientifically validated, and community-tailored nature-based solutions (NbS) in selected Pilot Demonstration Areas. The project explicitly addresses the hydrological and socio-ecological complexity of MAEs under multiple risk conditions. DRYAD employs an expanded interpretation of NbS, conceptualizing them as an "ecosystem of NbS" that includes intervention-, protection-, management-, and planning-oriented actions functioning in systemic interaction.
One of DRYAD’s tasks is to develop a novel, standardized framework addressing a key limitation in current NbS implementation in agro-silvo-pastoral ecosystems: the lack of information, thereby enabling wider upscaling and mainstreaming. The framework, termed NbS Abacus, is implemented through the systematic documentation and evaluation of thirteen NbS using comprehensive fact sheets developed with stakeholder input. Each NbS is assessed against a set of characteristics, including implementation requirements, targeted ecosystem services (classified according to the Common International Classification of Ecosystem Services), expected benefits, potential trade-offs, strengths, constraints, costs, policy relevance, and upscaling potential. While all NbS are multifunctional, they are classified according to their primary ecosystem service focus into water-, soil-, and biodiversity-related interventions.
Water-related NbS address key hydrological constraints in MAEs, such as strong precipitation seasonality and prolonged summer droughts. Examples include contour-aligned drainage ditches, dry detention ponds, and artificial ponds. The framework explicitly captures associated risks. These include, e.g., substrate clogging and groundwater contamination from polluted runoff. This enables risk-informed NbS design, implementation, and the selection of appropriate monitoring protocols and indicator sets.
MAEs have also experienced increasing degradation driven by contrasting land-use dynamics, notably land abandonment and intensification. Soil-related NbS aim to improve land management efficiency by enhancing soil water retention, fertility, and erosion regulation. Representative examples include adaptive grazing schemes, real-time livestock monitoring systems, and wildfire prevention measures.
Climate-induced drought poses a major threat to biodiversity in MAEs. Biodiversity-related NbS aim to restore or conserve ecological functioning through measures such as strategic forestation, agropastoral system reforestation, habitat islands, and remote sensing-based detection of tree decline. The framework accounts for both long-term ecological benefits and short-term socio-economic constraints, including infrastructure requirements, site biophysical limitations, maintenance costs, forage yield reductions, and temporary impacts on livestock productivity.
The NbS Abacus supports the uptake of NbS by providing harmonized, practice-oriented information on performance, costs, risks, and scalability. The framework and its NbS catalogue facilitate informed decision-making, replication, and mainstreaming across land management and climate adaptation strategies, with relevance for practitioners, advisors, policy-makers, and planners in Mediterranean and other drought-prone regions.
Acknowledgements. This research has received funding from the European Union’s Horizon Europe research and innovation programme under Grant Agreement No. 101156076 (DRYAD).
How to cite: Mendes, M. P., Salbitano, F., Lubczynski, M. W., Andreu, A., Silva, A., Carvalho, S., and Samper, J.: A novel assessment framework for Nature-based Solutions in Mediterranean agro-silvo-pastoral ecosystems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22240, https://doi.org/10.5194/egusphere-egu26-22240, 2026.
Urban streets are critical micro-environments where people experience disproportionately high exposure to air pollution and heat stress due to dense traffic, limited ventilation, and extensive surface sealing. Despite their importance for daily exposure and wellbeing, streets remain among the most challenging urban spaces for implementing effective climate adaptation and air-quality mitigation strategies at scales relevant to households and communities. This study is motivated by the need to translate evidence from street-scale environmental assessment into practical, inclusive, and actionable urban greening solutions. The primary objectives are threefold, first, we evaluates a set of street-level case studies to assess different combinations of green infrastructure (GI), including street trees, hedges, green walls, and pocket green spaces. Second, it integrates high-resolution street-scale modelling with in-situ measurements to quantify GI impacts, capture spatial variability, and identify context-specific trade-offs across contrasting street typologies. Third, the project translates scientific evidence into practice through the development of a decision-support framework and DIY Greening Cards, enabling residents, communities, and local authorities to select feasible, evidence-led greening interventions tailored to local constraints. To achieve these objectives, GP4Streets employs an integrated modelling–measurement framework. High-resolution street-scale dispersion and microclimate models are used to simulate changes in pollutant concentrations (e.g. PM2.5 and NO2) and thermal conditions arising from alternative GI scenarios. These simulations are complemented by in-situ measurements from fixed sensor networks deployed across streets with varying traffic intensity, and land-use characteristics, capturing real-world variability in air quality and thermal comfort. Model outputs and observations are jointly analysed to evaluate average effects, spatial heterogeneity, and the sensitivity of outcomes to street form, local emissions, vegetation characteristics, and meteorological conditions. Preliminary findings indicate that the effectiveness of GI at the street scale is highly context-dependent, with benefits strongly influenced by street configuration, vegetation type, and placement. While some GI combinations deliver measurable reductions in pollutant exposure and thermal stress, others introduce trade-offs related to airflow restriction or uneven distribution of benefits across the street canyon. Measurement results are further used to evaluate the model outcomes. By embedding scientific evidence within accessible DIY Greening cards and a decision-support tool, present work demonstrates how street-scale GI can be operationalised to support inclusive, scalable, and socially grounded approaches to urban climate adaptation and air-quality mitigation.
How to cite: Biswal, A., Sun, H., and Kumar, P.: Street-scale modelling, measurements, and participatory tools for climate-resilient urban greening, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10588, https://doi.org/10.5194/egusphere-egu26-10588, 2026.
The European GreenStorm project (Gromaire, Sage 2024; Seidl 2025) investigates the performance and resilience of nature-based solutions for urban stormwater management (NBSSW) under current and future climate extremes. To explore the potential and limitations of real-scale climate-chamber experiments, two experiments were conducted at the Sense-City facility to analyze the hydrological, thermal, and vegetation responses to heatwaves in 2024 (Seidl et al. 2025) and 2025.
The experiments focus on a 10-m-long and 6-m-high canyon street equipped with two types of NBSSW: stormwater trees and a rain garden. The Sense-City (IFSTTAR 2018) climate chamber allows controlling of air temperature, humidity, and radiation, enabling the reproduction of extreme conditions derived from observed heatwaves and future climate projections. The simulated climate scenario included a 5-day reference period representing typical summer conditions in Paris, followed by a 5-day heatwave based on the 95th percentile of RCP8.5 2023-2050 (Soubeyroux et al. 2024) projections and 2003 heatwave (Meteo France 2003).
A comprehensive monitoring system was deployed, including continuous measurements of meteorological variables, soil moisture and surface temperatures, complemented by repeated physiological observations of vegetation. Leaf pigments and stomatal conductance were measured twice each day with continuous monitoring of tree sapflow and stem diameter. These observations were used to assess both the physiological responses of different vegetation types to extreme climatic forcing in relation to NBSSW hydrological conditions.
Preliminary results highlight: (1) the ability of the climate chamber to reproduce global diurnal climate cycle and its limits to reproduce realistic climate gradients, (2) significant uncertainties associated with key climatic parameters, (3) fast adaptation of the studied vegetation to climate extremes in the presence of sufficient soil moisture reserve, and (4) contrasted responses between stormwater trees and the rain garden vegetation in terms of transpiration and physiological stress. These findings contribute to a better understanding of how experimental climate simulations can support the assessment of NBSSW resilience under future extreme climate conditions.
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GROMAIRE, Marie-Christine ,and SAGE, Jérémie, 2024. GREENSTORM. 2024. https://arceau-idf.fr/en/projects/greenstorm
IFSTTAR, 2018. Sense-City, Tester la ville de demain. Trajectoire. 2018. Vol.15, n juin, pp.7‑10.
METEO FRANCE, 2003. Bulletin climatique Aout 2003 Meteo France. https://donneespubliques.meteofrance.fr/donnees_libres/bulletins/BCM/202308.pdf
SEIDL, Martin, 2025. Le projet GreenStorm, c’est quoi ? Ingenius 15 septembre 2025. https://ingenius.ecoledesponts.fr/articles/le-projet-greenstorm-cest-quoi/
SEIDL, Martin, SANDOVAL, Santiago, SAGE, Jérémie, GROMAIRE, Marie-Christine, LAPORTE, Stephane ,and ULANOWSKI, Yann, 2025. EGU25-18974: Towards an understanding of the limits of extreme event studies on Nature Based Solutions Copernicus Meetings. https://meetingorganizer.copernicus.org/EGU25/EGU25-18974.html
SOUBEYROUX, Jean-Michel, DUBUISSON, Brigitte, BERNUS, Sebastien, SAMACOÏTS, Raphaëlle, ROUSSET, Fabienne, SCHNEIDER, Michel, DROUIN, Agathe, MADEC, Thumette, TARDY, Marc ,and CORRE, Lola, 2024. A quel climat s’adapter en France selon la TRACC? Meteo France. https://hal.science/hal-04797481v1
How to cite: Li, Y., Seidl, M., Techer, D., Sandoval, S., Ulanowski, Y., Laporte, S., Sage, J., and Gromaire, M.-C.: Extreme climate chamber experiments on nature-based solutions: insights from GreenStorm project, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14946, https://doi.org/10.5194/egusphere-egu26-14946, 2026.
Posters on site: Thu, 7 May, 14:00–15:45 | Hall X3
Nature-based Solutions (NbS) are increasingly promoted to enhance climate resilience and deliver ecosystem services such as flood mitigation and drought buffering. However, their effectiveness often depends on where they are implemented and which time horizon is evaluated. Current evaluations, typically based on hydrological models, rarely consider how spatial placement within a catchment or temporal factors such as forest age influence outcomes. This knowledge gap limits our ability to design NbS that maximize benefits across landscapes and over time.
We use hydrological modeling to assess the performance of NbS under varying spatial configurations and temporal conditions. We explore how these dimensions affect the distribution of surface, groundwater, and soil water across the landscape, identifying opportunities, constraints, and potential trade-offs for ecosystem service delivery. Our findings provide a framework for assessing NbS effectiveness across spatial and temporal scales to inform strategies that reduce climate risks and enhance long-term resilience.
How to cite: Wittmann, C., Weerts, A., de Vries, J., and Penning, E.: Spatio-temporal dynamics of Nature-based Solutions: implications for climate adaptation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1817, https://doi.org/10.5194/egusphere-egu26-1817, 2026.
Evidence of negative outcomes of Nature-based Solutions (NbS) for climate change adaptation initiatives is increasing. This occurs because these initiatives involve both decisions and processes between addressing multiple pressures and objectives that are called trade-offs. However, the identification of trade-offs remains difficult and the reasons why they occurred elusive. This review constructs an analytical framework for trade-off identification based on a qualitative exploratory review of the literature, which finds four main types of trade-offs with practical NbS examples in climate change adaptation. It also identifies three broad reasons for the trade-offs: transitional risks and uncertainties; lack of plural valuation in the landscape; and use of inappropriate indicators. The results are also understand trade-offs as an umbrella concept for concepts such as maladaptation, externalities, and ecosystem disservices. It also recognizes the importance of seeing trade-offs in decision-making and causality effects. While the framework provides a way to identify them, two countries are provided as case studies to determine if the trade-offs found in their NbS are intentional/unintentional or whether they can be reversible. The findings help us navigate the politics of prioritization in decision-making and imagine ways to negotiate trade-offs equitably.
How to cite: Portugal Del Pino, D.: Understanding trade-offs in nature-based solutions for climate change adaptation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2485, https://doi.org/10.5194/egusphere-egu26-2485, 2026.
Coastal landscapes cover only four percent of Earth’s land surface but host around thirty percent of the global population and support key ecosystems that deliver up to two thirds of global ecosystem-service value. Despite their ecological and socio-economic importance, these landscapes face increasingly entangled pressures, including sea level rise, coastal squeeze, biodiversity loss, and pollution. Nature-based Solutions (NbS) are increasingly recognized among promising adaptation strategies to these pressures, yet their implementation remains largely confined to small-scale pilots. The urgent need to scale up NbS for long term, large scale coastal adaptation continues to lag behind due to the intertwined complexities among biophysical, ecological, and socio-economic systems. To address this gap, we developed the Nature-based Building Blocks (NB3) Framework as a transdisciplinary, participatory approach in bridging successful pilot-scale NbS to large-scale coastal restoration. Co-developed across nine restoration pilots within the EU H2020 Rest-Coast project, the framework draws on two complementary, stakeholder-based methodological foundations-the Participative Downscaling Approach and the Input-Process-Output Model-to identify spatially explicit Coastal Units that integrate locally relevant biophysical, ecological, and socio-economic knowledge. Applying the framework across the pilot sites yielded an inventory of Nature-Based Building Blocks to support decision-makers in navigating coastal complexities when developing future upscaling strategies for their pilots. Adding to this inventory, participative practices across diverse coastal contexts revealed key insights into disciplinary gaps and participation biases that inform NbS upscaling research and implementation. The framework shows further potential for scaling out to other ecosystems, such as peatlands and wet forests (in ongoing collaboration with the EU Waterlands project), and scaling across geographical contexts, with an upcoming stakeholder-driven application in the Gediz Delta, Turkey.
How to cite: Arslan, C., Warner, J., and van Loon-Steensma, J.: Nature-based Building Blocks (NB3) Framework to support upscaling restoration through NbS in coastal adaptation: Theory, practice, and lessons learned, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1372, https://doi.org/10.5194/egusphere-egu26-1372, 2026.
As global demand for food, energy, and climate change mitigation continues to increase, decision-makers in these sectors must find suitable agricultural production strategies to meet Sustainable Development Goals. While several models have been created to aid in decision-making in these systems, there is a lack of robust integrated models that enable an understanding of the multidimensional trade-offs of these systems. Additionally, long-term field measurements for model calibration and optimization is always challenged. We therefore integrated with climate and crop growth model (DSSAT), fed into Life-Cycle Assessment tools (LCA) and economic analysis model using GIS-based integrated platform, and combining a ten-year field measurements of greenhouse gas emissions and soil organic carbon sequestration in a maize-wheat rotation system. The impact of soil organic amendment strategies (e.g. straw return, manure input) on crop yield, soil organic carbon (SOC) dynamics, carbon footprint and cost-benefit indicators were synthesized, and the synergies and trade-offs analysis were conducted at field and regional level to identify gaps and areas where policies should be tailored and targeted. Results showed that model can accurately evaluate grain yield and carbon balances of maize-wheat system and its response to synthesized fertilizer substitution practice. Soil organic amendment strategies (i.e.manure application, crop straw incorporation) increased the yield-scaled carbon footprint by 5.9% and 126.9% respectively, while simultaneously enhancing crop productivity and SOC compared conventional practices. The net benefit was $6.57/ha in maize-wheat cropping system (ten-year average) and the results showed that under low and medium prices for maize and wheat cultivation might difficult to meet the break-even point. Our study indicated that the global warming potential will be increased by long-term fertilization legacy effect, caution shall be made when providing guidance in organic amendments strategies. This discovery underscores the significance of long-term field measurements in emission assessment, providing theoretical support for the formulation of precise greenhouse gas emission inventories and regional sustainable agricultural policies.
How to cite: Yang, X. and Zhou, M.: Integrating spatial-explict life cycle assessment into multidimensional trade-offs analysis for soil organic amendment strategies, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2372, https://doi.org/10.5194/egusphere-egu26-2372, 2026.
One of the greatest challenges in building more resilient forestry lies in figuring out how to initiate changes in forest practices to better protect biodiversity and ecosystems, while operating within an already highly optimized and profit-oriented system. Although the scientific community is often very effective in diagnosing the weaknesses of current agricultural and forestry models and proposing innovative solutions, the transition from a poorly resilient, yet widely accepted state to amore adaptive but hypothetical one often faces significant on-the-ground realities. These include adapting the wood-production oriented management, overcoming legislative barriers or confronting the different expectations of local stakeholders.
The Landes of Gascony Forest is one of the largest man-made forests in Europe, located in southwestern France. The million hectares of maritime pine plantations and almost two centuries of its existence have shaped a deeply rooted forestry culture among local populations. This is associated with a highly intensive and optimized forest management, that rose diverse concerns under growing threats to the forest ecosystem and socio-economic resilience. Even the most severe disturbances in the past, such as the storms of 1999 and 2009 which damaged 60% of the area, or the large-scale forest fires of 2022 were not enough to bring about a change towards more resilient forest management practices, due to the lack of consolidated alternatives. The recent detection of the pine wood nematode is the latest dramatic opportunity to rethink our forest management system and landscape restoration strategies.
Selecting a demonstration area and engaging stakeholders through a living laboratory approach, as promoted by the SUPERB and TRANSFORMIT projects, has proven highly effective in creating a positive atmosphere for collaboration and mutual learning to aid in the development and adoption of new practices. Local stakeholders with diverse profiles (public, private, practitioners, NGOs, policy makers...) regularly become involved in the living lab to share experiences, guide research and experimentation, learn from the field trials and disseminate results.
Moreover, adopting a nature-based solution such as the establishment of diversified broadleaved hedgerows along maritime pine plantations offer both a real positive impact on biodiversity and resilience at the stand and landscape scale, while not compromising productive pine management. Scientific studies undertaken to understand the effect of diversified hedgerows on various species communities (insect, soil fauna, flora), on tree health issues, and on the vulnerability of the landscape to windstorms and fire have provided robust evidence to help convince stakeholders of the need to adapt their management practices.
Several years of hindsight for testing the establishment of new hedgerows in the pine forest has enabled refinement of the technical details, and has helped to anticipate plant supply and legislative constraints. The restoration efforts have resulted in the establishment of 50 km of newly planted hedgerows, partly funded through the engagement of a private charity to overcome economic barriers.
How to cite: de Guerry, B.: Broadleaved hedgerows as Nature-Based solution for restoring the resilience of Atlantic pine forests, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17717, https://doi.org/10.5194/egusphere-egu26-17717, 2026.
Among the many ecosystem services provided by forests, including raw material production, climate regulation, biodiversity and recreation, protection against gravitational natural hazards is particularly important in mountain regions. In Switzerland, protection forests represent approximately half of the total forest cover, and constitute a valuable and cost-effective nature-based solution. Yet, this protective function, alongside other forest ecosystem services, is rarely assessed (i.e., quantification, economic valuation) in a systematic and comparable manner. Therefore, our study aims to establish the state of the art regarding cost-benefit analyses (CBAs) of mountain protection forests and their ecosystem services, through a scoping review across N=5 databases and N=35 peer-reviewed publications and grey literature.
Results confirm the primary role of mountain forests in regulating gravitational hazards, particularly rockfalls and avalanches. Most importantly, this review highlights a significant lack of comprehensive CBAs addressing mountain protection forests and associated ecosystem services. Indeed, studies tend to rely on partial or service-specific economic assessments, often disregarding other beneficial forest functions. Moreover, external drivers such as climate change and forest disturbances (e.g., windthrow, insect and pest outbreaks, wildfires) are often neglected in existing literature, although they may influence the provision of ecosystem services.
Finally, despite the absence of a standardized methodology, largely due to variability in site conditions, CBAs remain a valuable tool for decision-makers in sustainable forest management, land-use planning, climate adaptation, and natural hazard mitigation.
How to cite: Meisburger, E., Scolobig, A., Stoffel, M., Linnerooth-Bayer, J., Martin, J., Aguilera, J., and Huland, E.: Cost-benefit analysis of protection forests and their ecosystem services: a Scoping review, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18111, https://doi.org/10.5194/egusphere-egu26-18111, 2026.
Urban areas in the Global South are highly vulnerable to climate-related hazards, yet systematic evidence on how adaptation is planned and operationalised remains limited. This study provides a structured assessment of urban climate adaptation by analysing 64 local adaptation plans from 37 South American cities with populations exceeding one million. We develop and apply a comparative analytical framework to measure the types of adaptation measures proposed, the role, purpose, and integration of nature-based solutions (NbS), and emerging patterns in urban adaptation planning.
Our analysis shows a strong emphasis on educational, informational, and behavioural measures, while engineering and technological interventions are comparatively underrepresented. Adaptation strategies differ systematically by hazard type: NbS are most frequently proposed for flood and heat risk reduction, whereas drought adaptation relies more heavily on engineering and technological approaches. We further show that national adaptation plans exert a measurable influence on local planning priorities, either enabling or constraining the uptake of NbS. Across cities, the findings reveal key gaps in adaptation planning, particularly in public health and risk-transfer measures, which are rarely considered.
By moving beyond qualitative accounts, this study offers a comparative and measurable evaluation of urban adaptation planning in South America. The findings provide actionable insights for policymakers, urban planners, and donors, and establish a basis for tracking progress, identifying blind spots, and strengthening the use of NbS in urban climate adaptation.
How to cite: Madruga de Brito, M., Sinner, V., Kuhlicke, C., and Nunes Carvalho, T. M.: The role of nature-based solutions in climate change adaptation: a systematic analysis of urban plans from South American cities, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2745, https://doi.org/10.5194/egusphere-egu26-2745, 2026.
With climate change amplifying heat island effects in cities, using Nature-based Solutions (NbS) for climate adaptation becomes essential, especially in areas where buildings are tightly packed. In rowhouse neighborhoods, where open space is scarce and air conditioning is often limited, NbS in the form of urban vegetation serve as a main way to adjust to the heat island effect. However, the integration of NbS into these constrained environments presents complex challenges regarding spatial scales and ecosystem service trade-offs. Though trees can lower air temperature through moisture release and shading, poor layout might slow wind movement or trap heat at ground level. This work aims to examine how planting decisions may affect the targets of maximizing indoor energy conservation and optimizing outdoor thermal comfort.
A combined simulation framework was created by linking a detailed microclimate model (ENVI-met) with a building energy simulation model (EnergyPlus) for considering indoor energy efficiency and outdoor thermal comfort. Applied in a rowhouse block in Baltimore, Maryland (USA), the simulation framework was validated against on-site sensor data. To examine the planting patterns' effect on both thermal comfort and energy efficiency, we created a pipeline to systematically generate tree configurations at the block scale, and we utilize morphological indices, including the aggregation index, nearest neighbor distance, and centripetal index, to categorize distinct vegetation patterns. The effects of spatial characteristics on simulated microclimatic and building performance will be determined by statistical analysis.
The microclimate model demonstrates high predictive accuracy, yielding a R-squared of 0.95 and a root mean square error (RMSE) of 0.831°C on air temperature in the reference day. Preliminary assessments suggest that the efficacy of NbS in this context is highly sensitive to the spatial arrangement of individual trees. Following the conducted simulation, further analysis aims to clarify the relationships between vegetation spatial heterogeneity, microclimatic variance, and building energy demand. The findings will provide practical, data-backed advice for decision-makers and community leaders to implement resilient, multi-purpose NbS planning strategies tailored to the specific layout of rowhouse neighborhoods.
How to cite: Dong, Y. and Wu, H.: Effects of Nature-based Solution Configurations on Indoor Energy and Outdoor Comfort in Rowhouse Neighborhoods: An Integrated Microclimate-Energy Simulation Approach, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8719, https://doi.org/10.5194/egusphere-egu26-8719, 2026.
Urban biodiversity is increasingly threatened by land-use change, habitat fragmentation, and intensive management practices. Within this context, urban trees represent a key nature-based solution (NbS) that simultaneously supports biodiversity, improves ecosystem functioning, and contributes to human well-being. Among the structural features provided by trees, tree-related microhabitats (e.g., cavities, deadwood, bark features, and epiphytic substrates), also called TreMs, are crucial for hosting a wide range of organisms, yet they remain underinvestigated in urban environments. This study examines the distribution and drivers of TreMs in an urban park ecosystem, focusing on Parco Colletta in Turin (NW Italy). A total of 423 trees were surveyed from a population of approximately 1,700 individuals. For each tree, we collected information on species identity, functional group (conifer versus broadleaf), origin (native versus non-native), diameter, height, planting configuration (groups, rows, or isolated trees), management intensity, and presence and type of TreMs. Overall, 97% of the surveyed trees hosted at least one TreM, with a total of 1,194 structures identified and an average of three TreM types per tree (range: 0–9). The most common types were dead branches, bark microsoil, and fork split at the intersection. Broadleaf species, particularly Fagus sylvatica L., Acer saccharinum L., and Quercus rubra L., exhibited the highest abundance of TreMs. Trees with low management intensity and standing dead individuals showed substantially higher TreM richness, highlighting the influence of management practices on habitat availability in urban environments. While several variables impacted TreM presence in univariate analyses, diameter and management intensity stood out as the primary explanatory factors. These findings highlight the value of TreMs as effective structural indicators of urban biodiversity and NbS performance. Incorporating biodiversity-focused management into urban green infrastructure planning can enhance the ecological value and resilience of urban ecosystems under ongoing environmental change.
How to cite: Piermattei, A., Borghesi, C. S., Maimone, F., Spina, P., Motta, R., Menon, N., and Campagnaro, T.: Urban trees as nature-based solutions: tree-related microhabitat diversity and management effects in Colletta Park (Turin, Italy), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11458, https://doi.org/10.5194/egusphere-egu26-11458, 2026.
Urban flooding has become an increasingly critical challenge for cities worldwide under climate change, rapid urbanization, and land-use intensification. Nature-based Solutions (NbS), including green infrastructure and land-based flood retention, are increasingly promoted as climate change adaptation strategies, yet their quantitative evaluation and integration into urban development planning remain limited. This study presents a scenario-based planning framework that applies a physically-based hydrodynamic model to evaluate the flood resilience implications of alternative NbS-oriented urban development strategies in Taiwan.
Tainan City was selected as the case study area due to its low-lying topography, rapid urban expansion, and high exposure to pluvial flooding. A Physiographic Drainage–Inundation (PHD) model was developed for the city using 40,147 non-structured computational grids, enabling detailed representation of urban drainage conditions, surface runoff processes, and flood propagation across development and surrounding areas. Future city development scenarios were constructed based on officially designated development zones under the City Development Plan. Flood simulations were conducted under climate change rainfall scenarios to compare pre-development and post-development flood depth–area relationships.
The results indicate that although flood depth changes within designated development areas are relatively limited, surrounding downstream and adjacent areas experience substantially increased flood depths and spatial extent, highlighting the importance of considering indirect and off-site impacts in climate change adaptation and urban planning decisions.
To explore adaptation pathways, three comparative flood mitigation scenarios were evaluated: (1) green infrastructure–based Nature-based Solutions within development areas, (2) landscape-scale flood retention using upstream agricultural land, and (3) a hybrid Nature-based Solution strategy combining limited green infrastructure with distributed agricultural flood retention. The analysis demonstrates that hybrid strategies can achieve comparable flood mitigation performance with significantly lower land requirements and greater implementation feasibility, particularly under constraints of land ownership and planning regulations.
The findings underline the value of scenario-based hydrodynamic modelling as a planning support tool for evaluating and mainstreaming hybrid Nature-based Solutions for climate change adaptation. By explicitly linking flood simulation outcomes with land-use allocation and development controls, this approach provides actionable evidence for integrating NbS-based flood resilience into city development plans and local spatial planning processes. The framework is transferable to other urbanizing regions facing increasing flood risks under climate change.
How to cite: Wu, J.-Y.: Enhancing Urban Flood Resilience through Scenario-Based Planning: Evaluating Hybrid Nature-based Solutions using a Physiographic Drainage–Inundation Model in Taiwan, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11809, https://doi.org/10.5194/egusphere-egu26-11809, 2026.
Urban flooding poses growing threat to cities due to climate change, requiring effective and context-specific adaptation strategies. This thesis evaluates to what extent Nature-based Solutions can contribute to climate change adaptation for flood hazard in Toronto, Canada, using a two-dimensional hydrodynamic model of the Don River catchment developed in HEC-RAS 2D. The model simulates flooding under a historical baseline rain event and climate change scenarios for multiple Shared Socioeconomic Pathways and climate model percentiles. Nature-based Solutions were implemented through a Multi-Criteria Analysis and represented via changes in infiltration, Manning’s roughness, and terrain. The contribution of Nature-based Solutions to climate change adaptation is evaluated through changes in flood extent, depth, and hazard patterns. The results demonstrate that the 2D model provides an improved representation of flood extent and identifies high-hazard areas not captured by a 1D approach, although at the cost of increased computational demand and calibration constraints. Climate change simulations showed increases in flood depth and inundation extent, with flood behaviour strongly influenced by variability within the climate model ensemble such that differences between percentiles of a single pathway exceeded differences between pathways themselves. Implemented Nature-based Solutions reduce local flood depths and peak discharges, particularly near river channels and downstream reaches, but their effects remain spatially heterogeneous and limited in magnitude under extreme rainfall, especially in urban areas away from channels. The findings indicate that Nature-based Solutions can support urban flood adaptation as complementary measures within broader, integrated strategies, but cannot offset climate-driven increases in flood hazard on their own. Overall, the results underscore the need for ensemble-based planning, low-regret and adaptive management approaches, and critical, context-sensitive interpretations of the role of Nature-based Solutions in climate change adaptation.
How to cite: De Castro Franca, F.: Hydraulic Modelling of Urban Flooding in Toronto: A 2D Approach to Evaluating Nature-based Solutions under Climate Change, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18549, https://doi.org/10.5194/egusphere-egu26-18549, 2026.
An increase in the occurrence of climate extremes has necessitated the integration of Nature-based solutions (NBS) such as green roofs into urban landscapes to help maintain hydrological balance. Green roofs are known to benefit biodiversity by adding vegetative spaces in urban areas and reducing the urban heat island effects. Runoff retention by green roofs helps delay the peak of the hydrograph, thereby preventing the overwhelming of drainage networks that often cause urban pluvial floods. Therefore, the design and planning of green roofs should be preceded by hydrological modelling studies to ensure their effectiveness against climate extremes that are highly likely in the future. As a high percentage of imperviousness generates quick hydrological responses from urban areas, it is necessary to perform hydrological modelling using fine-resolution meteorological data. This study proposes the downscaling of precipitation and temperature data from the climate model CMIP6 (SSP2-4.5 and SSP5-8.5) using the framework of Universal Multifractal (UM) theory.
Through UM, the meteorological fields can be characterised using two parameters: α (multifractality index) and (the mean intermittency codimension). The UM parameters for precipitation and temperature fields were estimated from the observed data using Double Trace Moment analysis. The climate data for the future scenarios from the CMIP6 model were then downscaled to a 6-minute resolution using the estimated UM parameters, employing a double cascade simulation process. This methodology helps conserve the heterogeneity and intermittencies of the field while generating extreme events that are imperative for studying the performance of urban systems. Further, temperature data were used to generate evapotranspiration data using an empirical parameterisation specific to the regions considered in the study. All meteorological data generated at a 6-minute resolution were used as input in a hydrological model to assess the performance of green roofs.
The hydrological modelling was performed for five regions in France: Paris, Lyon, Marseille, Nantes, and Strasbourg. Each region has specific regulations to ensure that the performance of green roofs complies with “Zero-Emission” criteria. Zero-emission rules define reference rainfall events to be contained within green roofs, such that the runoff retention/detention, and discharge rates are within limits that are favourable for the developmental conditions of the region. Thus, the Zero-Emission Metric (ZEM) used to estimate the performance of green roofs was defined as the ratio of the number of reference rainfall events that comply with the zero-emission rules to the total number of reference rainfall events in the region. The reference rainfall events specific to the regions were generated by renormalizing the downscaled precipitation data. The observations from the study indicated a decrease in the return period of reference rainfall events in the future scenarios, implying an increase in their frequency of occurrence. The performance of green roofs was found to decrease for the future scenarios: SSP2-4.5 and SSP5-8.5, due to the emergence of frequent climate extremes in future. The insights from the study highlight the requirement for effective hydrological modelling studies using region-specific meteorological data at fine resolution to design NBSs that are resilient to future climate extremes.
How to cite: Subrahmanian, S., Versini, P.-A., Sindt, L., Adrovic, A., and Perrin, R.: Application of Downscaled Meteorological Data in Hydrological Modelling to Assess the Impact of Climate Change on the Performance of Green Roofs, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18684, https://doi.org/10.5194/egusphere-egu26-18684, 2026.
Nature-based Solutions (NbS) are increasingly recognised as key strategies to address climate change adaptation while delivering biodiversity and social co-benefits. However, their implementation often remains fragmented, constrained by sectoral silos, limited stakeholder engagement, and insufficient capacities to manage ecological, social, and governance complexity. Beyond technical design, NbS require shared understanding, long-term cooperation, and co-development processes that bridge science, policy, and practice.
This contribution presents the NbS Summer School held in Milan (July 2025) as a practice-oriented learning and co-development experience through which elements of a bootcamp-based capacity development methodology for mission-driven investment planning, developed within NetworkNature, were piloted to support climate adaptation through education and stakeholder engagement. The School emerged from a cross-Task Force collaboration within the NetworkNature framework, integrating expertise on NbS data and assessment (TF1–TF2), co-creation and co-governance (TF6), and financing and business models (TF3), ensuring an integrated learning design. Organised in close connection with the NbS Italy HUB National Conference, and with financial support from Network Nature1 as part of its broader strategy to build a European-wide community of practice, the School adopted an intensive bootcamp-format intentionally designed to integrate technical, social, governance, and financial dimensions while linking academic knowledge, professional practice, and governance perspectives.
Over three days, participants engaged in site visits, expert lectures, and hands-on workshops addressing urban heat, flooding, air pollution, ecosystem services assessment, financing mechanisms, and co-governance models. Field cases across the Milan metropolitan area illustrated real-world NbS challenges, highlighting lessons on maintenance, monitoring gaps, underestimated long-term costs, trade-offs between speed and co-design, and the importance of social acceptance and communication. Workshops complemented field experiences by introducing decision-support tools, co-creative assessment approaches, innovative communication formats, and financing strategies.
A key outcome was the recognition of education itself as an enabling NbS infrastructure, where co-creation precedes co-governance and stakeholders can experiment with alternative governance constellations in a low-risk environment. The NbS Italy HUB acted as a boundary organisation, fostering continuity between learning, networking, and national-scale knowledge exchange.
Building on the Milan experience, the contribution anticipates the next NbS School and investment planning bootcamp in Bari. Key lessons underline the importance of structured dissemination, continuity between learning and practice, and the role of practitioner hubs in sustaining communities of practice beyond single events. These insights inform the Bari edition and provide a transferable reference model for other national NbS Hubs seeking to strengthen capacity building, stakeholder engagement, and long-term NbS implementation pathways.
[1] This project has received funding from the European Union´s Research Executive agency, under grant No.101082213.
How to cite: Sgrigna, G., Mahmoud, I., Aude, Z.-H., and Monica, A.: NbS Schools as Spaces for Learning, Knowledge Exchange and Co-Development in Climate Adaptation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20358, https://doi.org/10.5194/egusphere-egu26-20358, 2026.
The implementation of nature-based solutions can be a way to adapt urban environments to the current and future consequences of climate change such as flooding, heat waves and biodiversity loss. However, it is limited by its lack of integration into multi-criteria assessment tools and by an insufficient understanding of how the efficiency of NbS evolves across different spatial scales within a territory.
Therefore, an integrated method for assessing the multifunctionality of NbS across spatial scales is planned to be developed.
First, a multi-scale, distributed modelling is carried out to simulate thermo-hydric processes and fluxes (e.g. infiltration, evapotranspiration, runoff and temperature) associated with some NbS performances and climate adaptation measures at different urban scales.
Secondly, a systemic approach will be taken to study additional ecosystem services (e.g. habitat creation to enhance local biodiversity) and the environmental impacts of NbS (e.g. carbon emission and water consumption). These models will be implemented on different urban French pilot sites.
Finally, scale-invariant tools with a multifractal framework will be used to study the inputs and outputs maps and times series of the models. This will overcome the limitations of standard scores, which are only valid at a given resolution, and enable performance indicators to be computed independently of spatial scale while considering associated uncertainties.
Preliminary results will be presented here. They concern the multi-scale and distributed modelling under development. The Multi-hydro platform, developed by the HM&Co lab at ENPC, is coupled with SOLENE-Microclimat, in order to represent the interaction between both water and energy balances. They have been applied on one of the pilot sites. In parallel, modules to simulate the behavior of different nature-based solutions are also being developed. A trait-based model will also be integrated later to take the kinetics of plant development into account. These modules will be validated through experimental measurements.
This work is being carried out as a part of the French ANR project PENATE (Planning and Evaluating Nature-Based Solutions with local authorities), which aims to assess the performance and effectiveness of NbS as a tool for adapting urban environments to climate change.
How to cite: Tisseur, E., Versini, P.-A., Gires, A., and Schiopu, N.: Toward an integrated method for the multifunctional assessment of nature-based solutions in urban environments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22674, https://doi.org/10.5194/egusphere-egu26-22674, 2026.
Posters virtual: Wed, 6 May, 14:00–18:00 | vPoster spot 4
EGU26-5175 | ECS | Posters virtual | VPS32
Accessibility-driven habitat vulnerability in the tropical mountain landscape of Idukki district, IndiaWed, 06 May, 15:00–15:03 (CEST) vPoster spot 4
Mountain districts within biodiversity hotspots often experience increasing ecological pressure despite retaining extensive forest cover. In the Western Ghats of India, Idukki district has undergone rapid tourism expansion, infrastructure development, and land-use reconfiguration over the past decade. This study assesses how changes in urban nature accessibility and population demand influence ecosystem service distribution and habitat vulnerability using the InVEST modelling framework. Urban Nature Access and balance indicators accessibility, per-capita balance, and total population balance were evaluated alongside a Habitat Risk Assessment for 2011 and 2025. The results indicate a growing spatial mismatch between population demand and accessible natural spaces, with strongly negative urban nature balance values expanding across central and southern Idukki by 2025. Accessibility and population pressure have become increasingly concentrated along valley floors, plantation belts, and transport corridors, while large forested areas remain functionally inaccessible. Habitat Risk Assessment results show that human-modified land-cover classes experience disproportionately higher risk, with built-up areas exhibiting the highest mean risk (R̄ = 0.42), followed by plantations (R̄ = 0.38) and croplands (R̄ = 0.34). Deciduous forests display lower vulnerability (R̄ = 0.22), and water bodies remain largely unaffected (R̄ = 0.05). More than one-third of built-up and plantation landscapes fall within medium to high habitat risk categories. High-risk zones identified by the model spatially coincide with landslide-prone regions that experienced repeated slope failures during extreme monsoon years (2018–2020), particularly in tourism-intensive areas such as Munnar, Adimali, and Peermade. These patterns indicate that ecological vulnerability in Idukki is driven less by absolute forest loss than by accessibility-induced concentration of human activities within steep, geophysically fragile landscapes. The findings emphasize the importance of integrating accessibility-aware ecosystem service assessments with hazard-sensitive nature-based land-use planning to reduce ecological degradation and disaster risk while supporting sustainable tourism and development in the Western Ghats.
How to cite: Jalaja, D. and Singh, S.: Accessibility-driven habitat vulnerability in the tropical mountain landscape of Idukki district, India, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5175, https://doi.org/10.5194/egusphere-egu26-5175, 2026.
