The Swiss first responders and civil protection agencies work with scenarios to train and prepare for high-impact weather events. These scenarios have traditionally been focusing on events with moderate severity (return periods of 30 to 100 years). After the flood event in the Ahr catchment in summer 2021 a need for more extreme and worst-case scenarios has been recognized.   The online-tool flood dynamics (https://flooddynamics.floodrisk.ch/) addresses these needs.

We have used the UNSEEN method, i.e. re-forecast archives from S2S ensemble predictions,  to identify nine scenarios (storylines) of very extreme precipitation accumulations over 3 to 5 days in Switzerland that serve as meteorological input for the tool. The precipitation storylines are processed through a chain of hydrological and hydraulic models to identify flooded areas. The flooded areas are then intersected with exposure data (buildings, roads, residents, critical infrastructure such as hospitals) to illustrate and quantify the impacts of the flooding. Impacts are quantified i) in monetary damages on buildings, ii) as number of affected persons, workplaces, hospitals, nursing homes, and schools, and iii) as the locations and length of impassable roadsections. 

A novel aspect of the tool is that it provides physically plausible, temporally evolving flood storylines. The evolution of the flooded areas is illustrated at an hourly time-resolution. Because this information includes both flooded buildings and flooded and hence impassable roads, first responders can for example see how access to critical infrastructure such as hospitals or to their own headquarters is interrupted during the events. The detailed visualizations in the form of maps and time evolutions available in the tool provide information far beyond classical training scenarios. The tool furthermore provides a regional overview on the (timing of) flood impacts over large parts of Switzerland. This large-scale perspective is relevant to prepare emergency organisations for extreme events, when many river sections are affected at the same time.

How to cite: Martius, O., Mosimann, M., Munz, L., Kauzlaric, M., and Zischg, A.: A flood storyline tool to train first responders and civil protection forces, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-46, https://doi.org/10.5194/ems2023-46, 2023.

Climate change adaptation actions are vital in cities to prepare and adapt to advancing climate change, especially rapidly changing probabilities of extreme weather events. Although especially in Europe many cities have generated adaptation and climate risk management plans and improved decision-support also with respect to weather and climate risks, there is still much to do. Often, risk management actions are strongly activated only after experiencing negative impacts, for example, related to a severe flood causing substantial damages or even losses of lives. In a perfect world, however, in risk management all potential risks should be considered already beforehand, and either adapt to them or at least acknowledge these possible risks.

To support the Finnish cities’ preparedness for possible, yet not previously observed extreme weather events, the project LONGRISK designed a decision platform for strategic risk management, which generated an extensive dialogue between decision-makers and experts in three Finnish pilot cities (Helsinki, Tampere, Kotka). One of the main objectives of the project was to generate a “climate risk monitoring Dashboard” that demonstrates possible near-future extreme weather episodes and their impacts. More specifically, the Dashboard consisted of the synthetic reposition of the Copenhagen 2011 extreme cloudburst over each pilot city including the simulated flood impacts.

The Dashboard was a key tool in persuading city policymakers representing also the highest decision level (e.g. the Mayor) to engage in a Situation Room exercise, i.e., an internal dialogue especially on the possible gaps in their present adaptation level and chain of communication and decision-making. As a result, and especially due to the intensive internal dialogue, the decision-makers recognized their main vulnerabilities and weaknesses and generated a list of action items for further development.

This study presents the overall procedure of generating the Dashboard and running the Situation Rooms. Also, we present the method for generating the synthetic extreme weather events, such as the repositioned Copenhagen cloudburst and related urban flood simulations that are congruent with the climatological statistics and with CMIP6 climate projections.

How to cite: Mäkelä, A., Hukkinen, J., Pulliainen, J., Reinekoski, T., and Tuomenvirta, H.: Supporting climate risk management with synthetic weather extremes, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-613, https://doi.org/10.5194/ems2023-613, 2023.

The Prespa Lakes (shared by Albania, Greece and North Macedonia) are a biodiversity hotspot of global significance, and its water resources are of regional importance for agriculture and tourism. The catchment is protected by national parks, as well as by the transboundary “Prespa Park”. However, the lakes and biodiversity are threatened by future climate change which is amplified by intensive human impacts (e.g., water abstraction, pollution, and dam-building). Cost-effective and nature-based adaptation strategies are urgently needed to protect biodiversity & water resources.

The National Observatory of Athens (NOA) participates in research projects in the Prespa region since 2012. NOA transfers climate change knowledge to local decision makers and helps them design effective future-proof adaptation initiatives & strategies, in collaboration with the Society for the Protection of Prespa (SPP). The SPP is strongly involved in regional conservation management, through a network of stakeholders from all countries. The long-term collaboration between NOA and SPP is crucial for addressing regional climate change issues, disseminating information to local stakeholders, and implementing adaptation measures.

NOA research focussed on the assessment of future climate change hazards & risks on the lake-wetland system and local economy. Hydrological drought conditions will increase in the future, forcing large inter-annual lake level variability and a long-term declining water level trend, affecting the quantity & quality of the water resources. Furthermore, climate change will increase wildfire hazards, both in wetland and upland forest settings. These changes will increase the risk of biodiversity losses. Furthermore, a risk assessment of future climate change impacts on bean cultivation (the key local cash-crop) found that present bean varieties will have lower future yields.

These findings led to the [1] recommendation of introducing heat and drought-resistant bean varieties that are more water efficient, and the use of drip irrigation and wastewater recycling, and [2] development of guidelines making wetland management “climate proof” (i.e., sustainable & effective under future climate change). These new guidelines involve grazing and mechanical clearance of firebreaks in reedbeds, thus establishing bird foraging/fish-spawning areas under the lowest projected future water levels and protecting bird nesting sites under intensive future drought/fire conditions. Large quantities of plant material are also removed and used as fodder & fertiliser, consequently reducing the lake nutrient load and assisting the ecosystem to cope with climate change. Local farmers benefit from, and participate in, this arrangement, making management cost-effective and centred around local stakeholders.

Public institutions involved in land management are weak in all three lake-sharing countries. Successful uptake of adaptation measures depends on involvement of active local organisations and stakeholders. Strengthening local civil society, and access to high-quality risk assessment data, are amongst the most important factors in implementing climate change adaptation measures. 

Keywords: Climate change, Lake Prespa, wetland, biodiversity, adaptation, conservation management

How to cite: van der Schriek, T., Giannakopoulos, C., Koutseri, I., Malakou, M., and Kitsara, G.: Assessing future fire and drought risk to the lake-wetland system in the Prespa National Park (Greece), EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-57, https://doi.org/10.5194/ems2023-57, 2023.

Urban regeneration projects must address the growing challenges posed by climate change to ensure the creation of sustainable, resilient,and livable urban environments. This work proposes a comprehensive and collaborative framework to incorporate updated climate information into the urban regeneration process, focusing on the transformation of school yards in Greece. The study employs an interdisciplinary approach involving urban planners, climate change scientists, policymakers,and local communities.

The framework outlined in this study emphasizes the importance of integrating climate projections into urban planning processes, considering factors such as rising temperatures, shifting precipitation patterns, and the increasing frequency of extreme weather events. The use of climate projections on higher resolution, is necessary to assess the regional climate change signal and their impact over local areas and will contribute to adaptation plans mainly on vulnerable sectors to climate change (including building environment, land-use planning and regeneration, energy sector). Adopting sustainable and climate-resilient urban design principles is also crucial to mitigate urban heat island effects and improve climate change adaptation. These principles include green infrastructure, energy-efficient buildings, and mixed-use developments. Engagement with stakeholders throughout the planning process is a vital aspect of the proposed framework, as it facilitates the identification of locally relevant solutions that address the unique vulnerabilities and needs of communities involved. Additionally, the development and implementation of robust monitoring and evaluation frameworks are crucial for tracking the effectiveness of urban regeneration efforts in addressing climate change impacts.

The framework is applied to a case study involving the regeneration of two school yards located in the city center of the Municipality of Larissa, Greece (pilot action of the EU-funded project LIFE-IP AdaptInGR "Boosting the implementation of adaptation policy across Greece”). Through this case study, it is demonstrated the practical application of the proposed framework, highlighting its potential to guide urban regeneration projects that effectively respond to climate change challenges. Climate parameters and indices, related to the vulnerability of the pilot action, have been produced based on the ensemble mean of selected regional climate models, for two future periods and under three emission scenarios (RCP2.6, RCP4.5, RCP8.5). Several climate indices ,tailored to the climatic conditions of the case study area, were constructed taking into account the relevant climate risks: high temperatures (number of very hot days,maximum temperature), droughts (consecutive dry days), energy demand (cooling degree days), thermal stress (tropical nights, relative humidity,humidex).

By prioritizing the integration of future climate projections under different climate scenarios and adopting a collaborative approach, this study contributes to the advancement of urban regeneration practices that align with long-term climate change adaptation and mitigation goals. Ultimately, the proposed framework can serve as a blueprint for transforming school yards and other urban spaces into sustainable, resilient,and adaptive environments in the face of an uncertain climate future.

How to cite: Sebos, I., Kitsara, G., Karali, A., Giannakopoulos, A., Chioti, D., Katsaros, A., Nikolaidou, M., Assimacopoulos, D., and van der Schriek, T.: Climate-Resilient Urban Regeneration: Transforming School Yards for a Sustainable and Adaptive Future, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-73, https://doi.org/10.5194/ems2023-73, 2023.

Hail poses a significant risk to buildings, cars, and crops, making accurate hail impact assessments critical for decision makers in the insurance industry and agricultural sector. Here, we introduce a pre-operational hail impact assessment platform for Switzerland and multiple sectors that is co-created with potential end-users in the context of the project seamless coupling of kilometer-resolution weather predictions and climate simulations with hail impact assessments for multiple sectors (scClim, https://scclim.ethz.ch/). The platform provides both hindcasts and forecasts of hail impacts. The underlying hail damage models were developed with the open-source, event-based risk modeling platform CLIMADA (https://wcr.ethz.ch/research/climada.html). The applied vulnerability curves for buildings, cars, and crops were calibrated with damage data from 2002 to 2021, which was obtained from insurance companies. To assess hail damages from the previous day, the models rely on daily radar-based estimates of the maximum expected severe hail size (MESHS) or crowd-sourced hail reports gathered through a mobile application. To forecast hail damages in the upcoming day, the models utilize the output generated by the HAILCAST hail growth model, which is integrated into the numerical weather forecasting model COSMO. The COSMO model is operated in an ensemble configuration consisting of 11 members, allowing probabilistic short-term forecasts. The platform's first prototype was tested by stakeholders during the summer of 2023 to identify the most valuable content and presentation methods. Through this ongoing collaboration, we aim to create a comprehensive platform that addresses the various needs of stakeholders and enables them to make informed decisions when facing hail risks.

How to cite: Villiger, L., Schmid, T., Portmann, R., Calanca, P., and Bresch, D. N.: A pre-operational hail impact assessment platform for multiple sectors in Switzerland, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-594, https://doi.org/10.5194/ems2023-594, 2023.

The collection and management of data describing socio-economic impacts resulting from hydrometeorological hazards is critically important. Such Impact Data may be used to contextualize upcoming hazardous events, provide situational awareness, and track the efficacy of mitigating actions. Importantly, Impact Data can provide the observations of impacts necessary to evaluate the performance of Impact-based Forecasts and Warnings (IbFW).  There are many sources of publicly accessible impact data available including international organizations, governments, academic institutions, and news websites. Differences in the purpose, methodologies, format, and quality of collection across agencies has led to a fragmented and inconsistent picture of impacts to date, limiting their utility.

To understand the implications of using freely available impact data for the purpose of IbFW evaluation, seven freely available sources of impact data were assessed, and six types of bias interrogated (geographic, hazard, temporal, threshold, accounting, and systemic biases). 'Our analysis shows that different types of bias are present across the data sources investigated The biases affect the coverage, severity, timing, geographic scale, and accuracy of impact observations which influence their utility in IbFW evaluation. Despite these challenges, our assessment suggests that using a range of data sources together can provide a more holistic observation of the impacts of hydrometeorological events. Here we present results of the interrogation of Impact Data for IbFW evaluation, and the processing steps required to harmonize Impact Data across multiple sources for utilization within an evaluation workflow. Initial results of a routine objective IbFW evaluation approach are also presented, and opportunities and challenges of using Impact Data for IbFW evaluation highlighted.

How to cite: Wyatt, F. and Robbins, J.: Challenges and Opportunities Using Impact Data for Impact-based Forecast Verification., EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-28, https://doi.org/10.5194/ems2023-28, 2023.

The loss burden due to more intense and more frequent weather and climate events is increasing worldwide and causing casualties, economic damages and other adverse societal impacts. To mitigate these consequences and to support better informed decisions and therefore improved actions and responses, many National Hydrological and Meteorological Services are starting to provide services for weather and climate impacts as part of their operational routines. This requires National Hydrological and Meteorological Services to take a risk perspective, that in addition to the hazard-only perspective considers the potential for a given hazard event to inflict adverse consequences on society and attempts to quantify the uncertainties involved. We refer to impacts as the consequences of realised risks on natural and human systems. Risks result from dynamic interactions between weather- or climate-related hazards with the exposure (e.g. infrastructure, persons) and vulnerability of the affected human or ecological system to the hazards.

What are the consequences of such a change in perspective? Here we present our findings on this topic as an outcome of a working group on risks and impacts across three National Hydrological and Meteorological Services. We summarize the relevant strategic, methodological and technical steps and propose recommendations for the development and provision of impact-focused services at National Hydrological and Meteorological Services. In particular, we advocate for the use of one single framework, i.e., a fully fledged risk or hazard-exposure-vulnerability (HEV) setup operated at a National Hydrological and Meteorological Service. We show how such a framework integrates all existing forecast and prospective impact services and allows for flexible future extension driven by the evolving collaboration with partners, stakeholders and users.

How to cite: Geiger, T., Kienberger, S., Mühlbacher, G., and Röösli, T.: Integrating impacts into weather and climate services, EMS Annual Meeting 2023, Bratislava, Slovakia, 4–8 Sep 2023, EMS2023-596, https://doi.org/10.5194/ems2023-596, 2023.