Different nations have taken a range of approaches to the provision of their National Scenarios to provide decision-relevant information. Common challenges encountered by the providers of National Scenarios include how to capture, quantify and communicate uncertainties, the provision of information at high enough resolution to inform relevant applications, how to update and revise National Projections to capture new and emerging science, and understanding the user landscape to provide information of both the type and format that is relevant and accessible to a wide range of ‘next users’ and ‘end users’ with different levels of technical capacity and different specific requirements.
The session will take an inter-disciplinary view of the landscape of the provision and use of National Projections, and we particularly encourage submissions that consider:
• Latest plans and opportunities for developing new or updated National Projections products and services;
• Challenges in the provision of National climate information – including technical hurdles, information gaps and the challenges in providing information in ways that is relevant and accessible;
• New developments in the science or scenario products drawing from novel types of information that could form part of a National Climate information package – e.g. drawing from event Attribution, exploiting decadal forecasts to provide near-term projection information, provision of ‘High Impact, Low Likelihood’ scenarios, exploitation of convection-permitting downscaling and global high resolution models, the use of storylines approaches;
• Understanding user needs and the co-development of climate information and services;
• The future outlook and opportunities for national climate services, including developments such as CMIP7 and CORDEX, potential to use of AI emulation in projections products, and the implications of wider climate science and or policy developments.
In December 2025, KNMI published “An Extreme Report: Extreme weather in times of climate change”. The report presents detailed examples of plausible yet currently rare or unseen climate extremes and their potential impacts, aiming to support governments, professional stakeholders, and the public in preparing for present-day climate risks. The storylines cover a wide range of hazards and, where possible, were developed in collaboration with impact partners to link meteorological extremes to societal consequences. This presentation provides an overview of the cases, the methods used, and key challenges encountered during the project.
Why it matters
Are densely populated societies such as the Netherlands prepared for plausible but as-yet-unseen climate-fuelled extremes? We argue that proactive preparation is both relevant and necessary, especially because in times of climate change the past – to which society is accustomed- is no longer a good guide for what to expect in the near future. The Netherlands has a strong tradition of national climate scenarios, most recently updated in October 2023, which provide consistent long-term scenarios and a variety of derived products (e.g., change-numbers, maps and timeseries) for planning and stress-testing across sectors. However, these scenarios give limited attention to present-day climate extremes, many of which are already increasing in frequency or intensity due to climate change. An Extreme Report addresses this gap by focusing explicitly on near-term, high-impact extremes.
Nine unseen (compound) weather and climate extremes
The report describes nine storylines and their impacts: (1) A prolonged heat episode and the impact on the urban environment, (2) Wildfires and the impact on fire brigade demand, (3) Cold outbreak and the impact on gas demand, (4) Former hurricane hitting the Netherlands and the damage to houses and buildings, (5) Hurricane in the Dutch Caribbean and the damage to houses and buildings, (6) Summer drought and the impact of extremely low Rhine discharge on river transport, (7) Extreme convective rainfall and its impact on the local area, (8) Winter energy drought (“Dunkelflaute”) and the impact on the energy sector, and (9) Mosquitoes and the impact thereof on the emergence of West Nile virus.
How to cite: de Vries, H., Verheggen, B., Bloemendaal, N., Boonekamp, M., van Duinen, B., Dullaart, J., Lenderink, G., van Meijgaard, E., Mokkenstorm, L., Pereira Marghidan, C., van der Schrier, G., Siegmund, P., and van Voorst, L.: An ''Extreme'' Report: Increasing societal awareness for today's climate extremes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-23115, https://doi.org/10.5194/egusphere-egu26-23115, 2026.
The Atlantic Meridional Overturning Circulation (AMOC) is an important driver of the climate of Northwestern and Northern Europe, in particular the mild climate of Ireland. Although considered a low-likelihood high-impact scenario, recent studies suggest that a partial or full collapse of the AMOC may not be as unlikely as previously assumed. A strong decline or collapse of the AMOC would not just affect N(W)-Europe via reduced heat transport but also through changes in atmospheric circulation and sea level. Ireland’s national climate projections, standardised in Met Éireann’s TRANSLATE project, consist of dynamically and statistically downscaled global climate model simulations with varying degrees of AMOC decline during the 21st century. However, these projections currently neither subset simulations exhibiting strong AMOC weakening nor include dedicated AMOC storyline simulations. Here we outline a multi-pronged approach to address this gap using simulations that can also be beneficial to other national climate scenarios. We show analysis of global climate simulations that informs the choice of storylines to be created through dynamically downscaled regional climate simulations.
How to cite: Todt, M., Hanley, J., Nolan, P., O’Dea, E., and Semmler, T.: AMOC Storylines to inform Ireland’s National Climate Projections, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12549, https://doi.org/10.5194/egusphere-egu26-12549, 2026.
Climate CH2025 documents and explains past, present, and future climate change in Switzerland using the latest climate model data, providing the scientific basis for updating the National Adaptation Strategy after 2025. The Climate CH2025 scenarios use climate models from the Coupled Model Intercomparison Project (CMIP), integrating CMIP5-era Regional Climate Models (hereafter called RCMs) and CMIP6 General Circulation Models (GCMs) through both established and newly developed approaches based on Global Warming Levels (GWLs). Observations show that climate response in Switzerland has been particularly pronounced in comparison to other global land regions with mean near-surface air temperatures in 2024 exceeding the preindustrial reference period by 2.9 °C. This is a warming rate about two times faster than on global average. Most models simulate a substantially lower warming trend over this period. The recent warming was likely substantially enhanced by internal variability and by a decline of atmospheric aerosol loads since the 1980s. Regardless, a mismatch identified between RCMs and GCMs, where western Europe and Switzerland warm consistently more in GCMs than RCMs, in particular in spring and summer, limits confidence in the RCMs. This warming mismatch presents the main methodological challenge for Climate CH2025.
Several methodological choices were made in Climate CH2025 to reduce the influence of the RCM-GCM warming mismatch on Swiss climate change projections. The first was to set the “present day” base period to 1991-2020, consistent with the current norm period of the World Meteorological Organization. The observed global warming from the preindustrial period to the present day was used to calculate when each GCM reaches a given GWL, defined as a 30-year mean relative to preindustrial conditions. CMIP6 GCMs were brought in to incorporate the latest regional warming estimates, which were used in a regional time adjustment step that ensured RCMs and GCMs warmed the same amount regionally at each GWL. Once regional warming was aligned, local climate responses at 1.5 °C, 2 °C, and 3 °C of global warming could be reported. This method we call the “Block-Time-Shift" (BTS) approach. An advantage of using GWLs is that they relate warming on the global scale to Swiss warming, without relying on specific details in socioeconomic emissions scenarios. A disadvantage is that BTS cannot provide fully transient timeseries. Here we show how the BTS approach shaped results in Climate CH2025, particularly in comparison to earlier Swiss climate scenarios. We report on user feedback on GWLs from communication and technical standpoints and provide guidance for updating workflows from change at fixed time points to change at fixed points in global temperature.
How to cite: Lorenz, R., Merrifield Könz, A. L., Mülchi, R., Börsig, S., Fischer, E. M., Girlanda, O., Herrmann, M., Jonsdottir, L. S., Knutti, R., Kotlarski, S., Liniger, M. A., Prein, A., Schnadt Poberaj, C., Seneviratne, S. I., and Senoner, A. E.: The Swiss Climate CH2025 scenarios: Underlying methods and scientific challenges, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12173, https://doi.org/10.5194/egusphere-egu26-12173, 2026.
In late October 2025, the Norwegian Centre for Climate Services (NCCS) launched a new national climate assessment report for Norway (Dyrrdal et al., 2025), commissioned by the Norwegian Environment Agency. Alongside the report, we released a dataset featuring national daily climate and hydrological projections, including a comprehensive set of climate indicators. These indicators reflect projected changes relative to the current normal period (1991–2020), for both the mid-century (2041–2070) and end-of-century (2071–2100) periods.
The national projections are based on three emission scenarios: RCP2.6 (low), RCP4.5 (medium) and SSP3-7.0 (high). Due to the unavailability of downscaled ensembles of SSP-scenarios representing low and medium emissions from EURO-CORDEX, these are not included. For climate adaptation, the Norwegian government recommends basing assessments on a high emission scenario. Accordingly, the report places particular emphasis on results from the high emission scenario.
We present key findings from the report, including analyses of past and current climate conditions, hydrological normals, and projected future changes in climate, sea level, hydrology, and effects on natural hazards. Under the high emission scenario, the mean projected temperature increase for mainland Norway is 3.4 °C (2071–2100 relative to 1991–2020). Precipitation is projected to increase by 11 %, and runoff by 10 %.
Compared to the previous national climate assessment report (Hanssen-Bauer et al., 2015), the current ensemble displays a smaller projected temperature increase. This is due to both the lower radiative forcing in SSP3-7.0 compared to RCP8.5, and a shorter period between the reference and the end-of-century period. While the projected precipitation increase is also more moderate, the increase in runoff exceeds that of the previous report.
Additionally, we will give a brief overview of data distribution, outreach, and future work related to this updated national climate knowledge base. Specifically, we will highlight ongoing efforts to tailor climate information for Norwegian municipalities, emphasising co-development and user involvement throughout the process.
References:
Dyrrdal, A.V., Bakke, S.J., Hanssen-Bauer, I., Mayer, S., Nilsen, I.B., Nilsen, J.E.Ø., Paasche, Ø., Saloranta, T., Årthun, M. [red.] (2025) Klima i Norge – kunnskapsgrunnlag for klimatilpasning oppdatert i 2025 (in Norwegian), NCCS-rapport 1/2025, doi:10.60839/4rgq-nn84
Hanssen-Bauer et al., 2015: Klima i Norge 2100. Kunnskapsgrunnlaget for klimatilpasning oppdatert i 2015 (in Norwegian). NCCS report 02/2015.
How to cite: Dyrrdal, A. V., Simpson, M., Nilsen, I. B., Mayer, S., and Hygen, H. O.: New national projections and climate assessment report for Norway, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4847, https://doi.org/10.5194/egusphere-egu26-4847, 2026.
High-resolution convection-permitting climate simulations are essential for assessing climate risk at the national scale, but their high computational cost limits ensemble size and uncertainty sampling. In Ireland, national climate projections rely on multi-GCM, multi-RCM ensembles dynamically downscaled at considerable expense. Using the HARMONIE-Climate (HCLIM) model, we show that precipitation and temperature characteristics are comparable between 3 km and 5 km resolutions for ERA5-driven downscaled simulations produced using a nested GCM → 12 km HCLIM → CPM HCLIM approach over an Ireland–UK domain. This indicates that intermediate-resolution simulations can serve both as a cost-effective approach and alternatively as a basis for refinement using deep learning. Building on this result, we present initial findings from a deep learning model developed to emulate ≤3 km fields from 5 km ERA5-driven simulations, with a view to assessing whether this approach can provide high-resolution convection-permitting simulations more cost effectively for use in national climate projections.
How to cite: Hanley, J., Todt, M., Semmler, T., and O'Dea, E.: Towards Cost-effective Convection-Permitting Simulations for Ireland using Deep Learning, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19996, https://doi.org/10.5194/egusphere-egu26-19996, 2026.
The new Local Authority Climate Service (LACS) (launched in October 2024) offers a novel method of delivering UK climate projection information to end users. The LACS has been developed in response to a need from Local Authorities (LAs) for clear and authoritative information to raise awareness on the need to adapt to climate change, identifying and justifying priority risks and opportunities, and gathering evidence to support adaptation planning. The LACS platform enables LAs to: access ready-to-use climate information for their local area, develop a climate report summarising key results for awareness raising, obtain helpful resources and further support for adaptation planning. To explore how this method of delivering climate information is being used, tailored and communicated by users, twenty-two interviews were conducted between December 2024 and March 2025 with staff at Local and Combined Authorities in the UK. These were semi-structured, online interviews each lasting approx. 1 hour. We employed thematic analysis on the interview transcripts to explore current engagement with and anticipated use of the LACS, user feedback on functionality and usability of the service, as well as specific insights on the use of the LACS to progress organisational adaptation. Subsequently, the insights of these interviews fed into the development of three case studies which outline the current practical use of LACS in adaptation at the local level. The findings provide key insights for other European national met organisations or other climate service providers supporting adaptation and resilience planning at the local scale. Municipal planners need easy to access, easy to understand and easy to apply climate information, that moves beyond just greater granularity but considers climate change in the form of changing impacts relevant to their service delivery. Moving climate data away from the highly technical to the highly useable.
How to cite: Lorenz, S. and Walton, P.: The use and usability of the Local Authority Climate Service in UK Local Authorities, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19113, https://doi.org/10.5194/egusphere-egu26-19113, 2026.
To ensure consistency in adaptation policies, the French government has adopted a Reference Warming Trajectory for Adaptation (TRACC). This trajectory is based on current international commitments to limit greenhouse gas emissions and translates them into global warming levels (1.5°C, 2°C, and 3°C), associated with three time horizons (2030, 2050, and 2100, respectively). To address the needs of adaptation stakeholders, these global warming levels have been expressed in terms of regional climate change over French territories, including both mainland France and overseas regions. Discrepancies over mainland France between regional climate projections from the CMIP5 generation and recent warming estimates derived from observational constraints motivated the development of a new methodology. This approach relies on regional warming levels to characterize future climate change consistently with the reference warming trajectory. This presentation outlines the principles of this methodology and its extension to overseas territories. It also describes how this method has been applied to describe future climate change in terms of averages, variability, extremes, and sectoral indicators. Perspectives for updating the description of the reference warming trajectory, based on the downscaling of CMIP6 simulations, are also discussed. They rely on the synthesis of a wide range of diverse and recently developed data sources, including kilometer-scale regional climate models, coupled regional climate models, AI-based emulators, very high-resolution global climate models, and observational constraints.
How to cite: Corre, L., Ribes, A., Somot, S., and Drouin, A.: The French reference trajectory for climate changeadaptation (TRACC), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17393, https://doi.org/10.5194/egusphere-egu26-17393, 2026.
Over the past couple of decades, thanks to the sustained development of Global Climate Models (GCMs) combined with dedicated downscaling strategies such as regional climate modelling or statistical downscaling, climate projections and associated services are now increasingly available across many regions, particularly in nations of the Global North like France. However, whereas this is the case for continental France, the country includes numerous overseas territories, most of them being small islands in the tropical Atlantic, Indian and Pacific Oceans, where this information was only partially available until recently, if at all.
Here we present the recent development of ensembles of climate projections for most French tropical overseas territories (French West Indies and Guiana, Reunion Island, Mayotte, New Caledonia and French Polynesia), complemented with services in the form of climate information provided for different regional warming levels. The ensembles consist in the blending of data from global climate models (CMIP6), regional climate models (e.g. CORDEX), high-resolution global models and convection-permitting models where available. The models are evaluated against gridded and local observations with a focus on important regional climate processes, and selected accordingly for each domain. Fine-scale reference products for daily surface temperature and precipitation are developed for each territory. They combine long-term weather station observations with high-resolution data from either evaluation simulations driven by the ERA5 reanalysis or numerical weather prediction models. These products are then used to bias-correct and statistically downscale model fields, thereby providing kilometer-scale ensembles of transient climate simulations for each territory over both the historical and future periods, which are made freely available on national climate data portals (DRIAS, Climadiag Commune).
In addition, local temperature observations are used to constrain warming projections from CMIP6 for each territory, in order to compute regional warming levels corresponding to global warming levels +1.5°C, +2°C and +3°C. Following the national reference warming trajectory for adaptation to climate change (TRACC), a framework that has been previously applied over continental France to guide adaptation policies, climate indices are computed for these regional warming levels from the aforementioned climate projections and also made freely available. In addition to generic indices (e.g. number of hot days/nights, of heavy precipitation days etc.), tailored indices for the agriculture, water resource, energy, public health and disaster management (wildfires, coastal hazards) sectors are being developed using local impact data from various stakeholders.
Future extensions include regional climate model emulators previously developed for European domains. They show encouraging results for tropical islands and are expected to make key contributions to the characterization and understanding of climate projection uncertainties in these data-scarce regions.
How to cite: Belmadani, A., Drouin, A., Cantet, P., Casnin, A., Corre, L., de Saint-Aubin, C., Dubois, C., Faure, G., Legrand, R., and Peyrillé, P.: Developing climate projections and services in data-scarce regions: the case of French tropical overseas territories, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11145, https://doi.org/10.5194/egusphere-egu26-11145, 2026.
The rapidly increasing demand for usable, credible and legitimate climate services, driven partly by the European Union’s (EU) commitment to building a resilient Europe (see e.g. EU commission doc no. 16856/25) is coinciding with the European Union’s “New approach to enable global leadership of EU standards promoting values and a resilient, green and digital Single Market” (2022). This “New approach” prompted a standardisation request on climate services to the European standardisation body CEN/CENELEC on the part of the EU commission (C(2025)6809 – Standardisation request M/617) which was adopted on 15 October 2025.
While this policy context already specifies a particular path to standardisation, it still raises several epistemological and social questions for how and what should be standardised in climate services. First of all, standardisation is a social process that, especially when developed through formal channels such as CEN/CENELEC, is based on a consensus of experts that create harmonization through guidelines and rules. This is a form of knowledge governance that requires considerations about who counts as an expert and how consensus should be achieved, raising issues about the equitability of standardisation. Second, the requirements and recommendations of standards aim at promoting the comparability and reproducibility of a service, which raises technical and economic considerations in a market that is currently composed of both governmental and private climate service providers, which operate
In this contribution, we describe how the considerations above materialize in our work in Climateurope2, a Horizon Europe coordination and support action which, amongst other things, aims at supporting the equitable standardisation of climate services. The analytical approach to supporting standardisation developed by the project involves dividing climate services into four components: the context in which the service is developed and of the decision space it supports, the knowledge systems that are included in the service development and provision, the ecosystem of actors involved in the service, and finally the delivery mode and evaluation of the service. The project has also developed a framework for supporting standardisation which guides the analysis of each service component through an identification of existing tools of governance, an analysis of existing standards, the identification of pros and cons of standardisation and key questions to support the standardisation process itself.
After describing analytical questions raised by the framework for the different components of climate services, we focus on the possible differences that answers to these questions raise for knowledge governance through standardisation and standards for public climate service providers, such as national hydrological and meteorological services, and private providers. These two different groups are characterized by different funding structures and different economic motivations and therefore different social dynamics. In particular, there are differences in considerations about equitability, transparency, and benefits and drawbacks of standardisation that the framework raises for these different groups. While this analysis is currently still in progress, these open considerations need to be addressed by the climate services community at large to achieve the EU’s goals of its “New approach”.
How to cite: Lera St.Clair, A., Baldissera Paccheti, M., Zorita, S., Paz, J., Checchia, P., Grainger, S., and Doblas-Reyes, F.: A framework for standardising climate services: advances and challenges, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19256, https://doi.org/10.5194/egusphere-egu26-19256, 2026.
This paper conceptualises the future of artificial intelligence (AI)-enabled public climate services as publicly governed and publicly funded digital infrastructures that provide climate data, forecasts, risk assessments, and decision-support tools through AI-driven analytics and natural-language, prompt-based interfaces. Climate services are increasingly central to climate governance, underpinning decision-making in areas such as energy systems, infrastructure planning, finance, and local adaptation. At the same time, the rapid integration of AI, particularly generative and machine-learning systems, is transforming how climate information is produced, accessed, and interpreted. AI-enabled climate services offer significant opportunities for process automation, optimisation, personalised information delivery, and the translation of complex climate data into actionable knowledge for diverse users. However, the growing reliance on privately controlled algorithms, data infrastructures, and computing facilities raises critical concerns related to governance, transparency, accountability, and trust. While the technical architecture of climate services increasingly relies on advanced machine learning and large-scale climate models, their legitimacy as public services depends on governance arrangements that prioritise public value, equity, and long-term societal benefit over profit maximisation. The tension between the public mandate of climate services and the private nature of much contemporary AI infrastructure challenges traditional notions of openness and publicness. Using the PESTLE framework, the paper analyses the political, economic, social, technological, legal, and environmental dimensions shaping the co-production value chain of AI-enabled climate services. This approach highlights both risks, such as market concentration, reduced transparency, and unequal access, and opportunities, including enhanced accessibility, improved decision support, and strengthened climate resilience. The paper argues for the urgent development of a pan-European, decentralised public climate service built on sovereign AI infrastructure and open governance principles. Such an initiative would support democratic control over climate intelligence, advance digital sovereignty, and align technological innovation with climate justice and the twin digital and green transitions.
How to cite: Larosa, F., Calmanti, S., De Felice, M., and Petitta, M.: Public mandate, private algorithms: the urgent case for Public Climate Services in the AI age, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7584, https://doi.org/10.5194/egusphere-egu26-7584, 2026.
National climate scenarios provide a consistent translation of global and regional climate projections into information relevant for impact modelling and decision-making. Here, we present the development of a new set of national climate scenarios for Belgium based on regional climate model (RCM) simulations at convection-permitting scale. The ensemble comprises three RCMs (ALARO, MAR, and COSMO-CLM) that simulate the present-day climate and two future 20-year periods corresponding to global warming levels of +2 °C and +3 °C. The choice of global climate models and the downscaling approach specifically target climate extremes, including heatwaves and heavy precipitation events. Accordingly, boundary conditions are provided by CMIP6 models selected for their demonstrated skill in simulating these extremes. The performance of the three RCMs is evaluated for the present-day period based on their ability to simulate key climate variables. From the raw model output, we co-develop a set of climate indicators with key stakeholders, who also contribute to defining the format of the final products. The resulting national climate scenarios provide a robust basis for assessing climate impacts across multiple sectors, including agriculture, health, and water management, and for supporting adaptation planning to future climate extremes in Belgium.
How to cite: Vandelanotte, K., Vanderkelen, I., Ghilain, N., Serras, F., Brajkovic, J., Van de Vyver, H., Van Lipzig, N., Fettweis, X., Caluwaerts, S., Lauwaet, D., De Troch, R., Termonia, P., and Van Schaeybroeck, B.: Belgian National Climate Scenarios derived from convection-permitting regional climate models, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12385, https://doi.org/10.5194/egusphere-egu26-12385, 2026.
The growing volume and structural diversity of the CMIP6 archive [1] has made the selection of representative models for regional and country-scale impact assessments increasingly non-trivial. Although full-ensemble approaches are valuable for characterizing uncertainty, computational and operational constraints often require downstream users, for example dynamical downscaling initiatives such as CORDEX, sectoral impact modelling, and climate risk assessment, to work with small sub-ensembles. These subsets are commonly chosen opportunistically or inherited from static lists, which can under-sample plausible regional futures and over-represent closely related models. We present a configurable framework for selecting regionally tailored sub-ensembles from CMIP6 when computational or operational constraints preclude using the full ensemble. The framework integrates three decision dimensions: model independence, historical fidelity, and representativeness of the projected response spread of the full CMIP6 ensemble.
Model independence is quantified via unsupervised learning by embedding models in a feature space derived from regional climate responses and clustering them into families, enabling the selection procedure to reduce redundancy by avoiding highly similar model behaviour. Historical fidelity is assessed using core variables (near-surface air temperature, precipitation, and sea-level pressure) and complementary metrics that summarize both bias magnitude and pattern fidelity. These are combined into a composite score that penalizes single-metric failure while remaining interpretable. To preserve coverage of plausible regional futures, models are simultaneously evaluated in a future-response space defined by end-of-century changes in temperature and precipitation, with the option to include additional proxies relevant to extremes. In the spirit of recent independence–performance–spread selection approaches (e.g., ClimSIPS [2]), we emphasize country-scale customization, explicit trade-offs, and fully transparent diagnostics.
The criteria are integrated into a multi-objective selection engine that recommends subsets of a user-specified size. The process is customizable, allowing users to adjust weights assigned to performance, spread coverage, and independence, and to impose constraints on spatial resolution. We illustrate how recommended subsets can differ across contrasting climatic regions and user priorities, supporting robust and documented model selection for regional assessments and downscaling workflows.
References
[1] Eyring, V., et al.: Overview of the Coupled Model Intercomparison Project Phase 6 (CMIP6) experimental design and organization, Geosci. Model Dev., 9, 1937–1958, 2016, doi:10.5194/gmd-9-1937-2016.
[2] Merrifield, A. L., Brunner, L., Lorenz, R., Humphrey, V., Knutti, R.: Climate model Selection by Independence, Performance, and Spread (ClimSIPS) for regional applications, EGUsphere, 2023, doi:10.5194/egusphere-2022-1520.
Acknowledgements
The authors acknowledge the contribution of the General Secretariat of Research and Technology of Greece for supporting this study within the framework of the project “Support the upgrading of the operation of the National Network on Climate Change (CLIMPACT)” under Grant 2023NA11900001.
How to cite: Tsilimigkras, A. and Koutroulis, A.: Beyond Opportunistic Selection: A Customizable, Multi-Objective Framework for Country-Scale CMIP6 Sub-Ensembles, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14502, https://doi.org/10.5194/egusphere-egu26-14502, 2026.
Coastal climate services to support adaptation to sea level rise are developing rapidly in Europe. However, they remain widely underused today, primarily due to the persistent gap between the information provided and the decision-making contexts of stakeholders. This is despite significant co-production efforts between involved scientists and occasional voluntary users.
Here, we propose a new perspective targeting local state services in France. These services play a key role in major public decision planning at local scale in several countries. Nevertheless, their perception of effective adaptation to sea-level rise, as well as their climate information needs to support local authorities in adequately planning territorial development, remain unclear.
In this study, we therefore (1) systematically explore what kind of information local French state services need to plan sea level rise adaptation and (2) compare these needs with the information currently available through emerging European broadscale climate services. Using exploratory interviews and an online survey, we produced a national map of the perception of adaptation by local state services. Our findings indicate that most local authorities are still in an assessment phase, with only a few implementing adaptation measures that go beyond the mainstream coastal defence and dyke management.
In many regions, local state services consider sea level rise scenario by 2100 that are higher than national risk legislation requirement, and closer to the state-of-art academic knowledge. Climate information represents only a small part of their overall needs, which are mainly turned toward legal expertise, shared experiences, clarification of national rules, land acquisition strategy, financing, or planning tools. Legitimate standardised sea-level rise information deployed nationally are nevertheless considered useful to focus local discussions on effective action. Furthermore, although the European Coastal Climate Core services (CoCliCo) cannot be used easily by our stakeholders, our results reveal untapped potential: with additional work, including layout, these datasets enable regional comparisons, giving useful rough estimates, and may help to prioritise local government actions, and schedule in time and space their response.
To reach their goals and be used widely, climate services must be developed strategically, focusing on knowledge brokers such as local state services whose changing practices, for example through the co-production process, will affect a large population.
How to cite: Gourdon, A., Le Cozannet, G., Costa, S., Meur Ferec, C., and Thieblemont, R.: Narrowing the gap between climate services and adaptation to sea-level rise: perspective of local state authorities in France, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17860, https://doi.org/10.5194/egusphere-egu26-17860, 2026.
There is high demand for reliable climate information. But which aspects are most crucial for the development of useful and usable climate services, i.e. provision of products and services besides pure data? Which implications can be derived for climate service providers? The project Use.AT targeted these questions to inform the development of the next Austrian climate scenarios within a national, multidisciplinary process called Klimaszenarien.AT. In detail, the project
- examined the providers’ perspectives by looking at other countries with long-standing experiences in providing and evaluating climate services like UK, CH, DE, NL and Austria.
- focused on the users themselves: Who used the current Austrian climate scenarios ÖKS15? Who could and should use them in the future? What are users’ needs, requirements, and challenges? And which role does ÖKS15 play in climate-sensitive decision making?
- investigated the vast field of climate communication: Which aspects of effective climate communication and climate service provision can be found in the literature? How do existing products compare considering those criteria? Are they of different relevance for different user groups?
Using a mixed-method approach – literature research, surveys, interviews and focus groups –new insights on the needs and rationales of user groups concerning climate information and derived services were discovered. These now inform the development of a communication strategy for Klimaszenarien.AT, shaping the products and formats that are tailored to three different user levels: (i) `explorers’ that mostly need interpretation in the form of fact sheets, figures and content ready for social media, (ii) `practitioners´ that need tools and interfaces suitable for their everyday use to make use of the new localised climate scenarios, and (iii) `specialists´ that need the raw data themselves, accompanied by tutorials and uncertainty information. Therefore, the communication strategy aims to tailor the products to the relevant user groups needs, guide their navigation towards those products and services they really need and simplify access to data, web- and print services. The presentation will focus on the corner stones of the communications strategy, as well as recommendations for (inter)national climate service providers resulting from the results and experiences of the Use.AT project.
How to cite: Becsi, B., Mainetti, L., Schellander-Gorgas, T., Bügelmayer-Blaschek, M., Berg, R., Brenner-Fließer, M., Formayer, H., Müller, P., Schwarz, M., Schwarzinger, S., Seebauer, S., Themessl, M., Tschannett, S., Tötzer, T., and Wolf, A. and the Additional Members of the Steering Committee of Klimaszenarien.AT: Use.AT and Klimaszenarien.AT – a scientifically sound approach for user friendly, useful and usable climate scenarios, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19662, https://doi.org/10.5194/egusphere-egu26-19662, 2026.
TRANSLATE is a Met Éireann led initiative to standardise future climate scenarios for Ireland. It is a multidisciplinary programme, extending beyond climate science and services to include disciplines such as engineering, social science, visual and creative arts and communications. TRANSLATE’s primary aim is to mainstream national climate information to support the development of effective decision relevant climate services. TRANSLATE aims to achieve the following:
- Develop robust, standardised national climate scenaios from annual to climate timescales.
- Develop scalable and reproducible climate services.
- Enhance the uptake of climate information.
- Enhance the communication across all audiences.
- Support the National Framework for Climate Services in strengthening the national climate services community .
Data from TRANSLATE underpins many national and local climate directives. It feeds directly into the National Framework for Climate Services to support climate services development, coordination and standardisation and Climate Ireland, the national portal for climate adaptation. It is embedded within the National Adaptation Framework and the National Climate Change Risk Assessment supporting local climate action and sectoral adaptation plans. It is critical that information and services from the programme remain relevant and robust to ensure policy and decisions are based on the most accurate and up to date climate information, as well as ensuring that decision makers have access to the highest quality climate data when required and consistency across planning cycles.
TRANSLATE is beginning its 3rd iteration. This phase marks a significant expansion to the programme in scope and funding. There are four pillars,
- Underpinning data
- Understanding climate extremes
- Climate Services
- Communication
The provision of national climate information can be challenging and each pillar while expanding on existing work also seeks to address the identified gaps and challenges from previous phases. These include technical and scientific hurdles, information gaps and challenges in communication of information and uncertainty in a way that is both relevant and accessible.
Here we look across the programme from phase 1- 3 exploring the lessons learned, what challenges were encountered and how the programme is working to overcome them. We will explore the latest plans and opportunities within each pillar drawing from emerging science and understanding within climate science. We will highlight plans to combine different strands of climate information, the use of storyline approaches as well as challenges around data, extremes, uncertainty and seamless information. Finally, we will look to the future – CMIP7, developments in AI and steer from Europe and what the implications of these may be for the next phase of TRANSLATE.
How to cite: Scannell, C., Nolan, P., O'Brien, E., Holloway, P., Ryan, P., Murphy, C., and Aryanpur, V.: TRANSLATE: Met Éireann’s approach to standardised national climate change scenarios , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19915, https://doi.org/10.5194/egusphere-egu26-19915, 2026.
Extreme weather events have a disproportionate impact on society and are among the most tangible manifestations of anthropogenic climate change. Their inclusion in National climate services is therefore essential for informing climate risk assessments and adaptation planning. Framing future projections through storyline-based approaches anchored in well-remembered historical events offers a powerful means of connecting climate statistics to societal experience, thereby potentially improving understanding and usability.
Here, we revisit the exceptional summer of 1976, now 50 years ago, which affected large parts of north-western Europe, including the Netherlands, Belgium, and the United Kingdom. 1976 remains one of the most severe drought and heat events in the instrumental record. The event was preconditioned by dry conditions in 1975 and the preceding winter, which depleted soil moisture and groundwater reserves, followed by persistent heatwave conditions during summer 1976 that further intensified drought through enhanced evapotranspiration.
Using Pseudo Global Warming (PGW) experiments with a regional climate model, we place the 1976 event in present-day and future climate contexts. By conditioning on the observed large-scale circulation patterns, we quantify how the intensity and duration of drought and heat would change in progressively warmer climates. This approach allows a direct comparison between historically experienced extremes and plausible future analogues, and facilitates linkage with probabilistic regional climate projections.
We aim to test whether such event-based frameworks for National Climate Scenarios and climate services, support communication of future climate risks, better inform stress-testing of adaptation strategies, and enhance stakeholder engagement.
How to cite: van der Wiel, K., Dullaart, J., Lenderink, G., de Vries, H., van Meijgaard, E., and van Dalum, C.: Event-based learning? Revisiting the 1976 drought and heatwave in a changing climate, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-23058, https://doi.org/10.5194/egusphere-egu26-23058, 2026.
UK National Climate Scenarios currently provided through the UKCP18 projection set provide a common basis for national risk assessment and adaptation planning. The UK is now looking towards a new generation of UK Climate Information (UKCI) products, and here we describe the current thinking around what might be included.
We have recently assessed whether there is a need to update this set of products to address user needs and exploit latest science opportunities. We have found that user needs have evolved significantly since the UKCP18 projections were designed, leaving significant gaps between needs and available information, specifically in the areas of present-day climate and recent climate events, representation of wider uncertainties (including both a range of plausible emissions scenarios, and more ‘extreme’ or high impact, low likelihood’ scenarios and information to inform the marine climate impacts community. We have also identified areas of new science capability which offer new opportunities to address these user needs. These advances include improvements in the traditional approaches employed in the provision of future climate projections for adaptation planning (updated global model ensembles, various downscaling approaches including convective permitting regional projections, improvements in constraining model ensembles), developments in a wider range techniques are increasingly being used in the assessment of climate resilience. Recent studies of unseen extreme events in large ensembles of present-day climate, operational rapid event attribution, new simulations and understanding around earth system tipping points and new coupled regional downscaling capability.
How to cite: McSweeney, C. and Lowe, J.: Towards a new package of UK Climate Information for national risk assessment and adaptation planning, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-23081, https://doi.org/10.5194/egusphere-egu26-23081, 2026.
Posters virtual: Wed, 6 May, 14:00–18:00 | vPoster spot 4
EGU26-17146 | Posters virtual | VPS32
Lessons in climate service development from Klimaatlas, the Danish National Climate Atlas.Wed, 06 May, 14:48–14:51 (CEST) vPoster spot 4
Responding to the challenges of a changing climate requires information that is relevant and actionable at the local scale where adaptation actions take place. To address these needs within Denmark, Klimaatlas, the Danish National Climate Atlas, was developed to provide information to ministries, regional authorities, businesses and citizens about climate change in Denmark. Here we present the lessons learnt since the inception of the project in 2018, with a focus on those that are relevant to the development of similar tools in other regions. We will examine issues around the conception and setup of the climate service, particularly the need to identify users, work with champions and set limits. Communication is a critical aspect of such a service and we will discuss our approach of communicating on multiple levels, and taking up the challenge of uncertainty. Updatability, maintenance and operationalisation are also key, and the merits of the “rolling-releases” model used by Klimaatlas will be discussed, together with our efforts to open our codebase via the KAPy project. Finally, we discuss issues around future maintenance and possible expansions of Klimaatlas, including the use of convection permitting simulations, incorporation of compound events, updates between IPCC cycles and extensions to new sectors.
How to cite: Payne, M. R.: Lessons in climate service development from Klimaatlas, the Danish National Climate Atlas., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17146, https://doi.org/10.5194/egusphere-egu26-17146, 2026.
