Local Climate Risks in sight of realistic climate targets: Projecting Co-occurrence of Heat Extremes in Central Europe Using Downscaled CMIP6 and Regional Scenarios

Humanity will face the challenge of adapting to the impacts of global warming besides those that have already occurred, even if political ambitions are realized. Challenges differ regionally and include a wide range of weather extremes, which means not only the increasing frequency of dangerous “usual” climatic events but also unprecedented impacts outside of the climate system's natural variability.  Many regions globally, including Central Europe, have already experienced changes in climate extremes higher than the internal variability of the climate system. The signal is shown to be especially robust in case of heat extremes, such as warm days or warm nights, with signals reflecting unusual or even unfamiliar conditions.  

Our analysis focuses on heat-related extreme events, including their co-occurrence. We use a targeted subset of CMIP6 models known for their robust performance over Europe, supplemented by high-resolution regional climate scenarios. We employed different downscaling techniques, including convection-permitting regional climate simulation, to evaluate the sensitivity of results to methodological choices and to better capture regional-to-local-scale climate signals. Rather than focusing on specific emissions scenario pathways, we analyse projections at different levels of global warming. This approach allows us to explore the manifestation of heat-related extremes under a range of plausible global temperature increases, including outcomes that reflect both current policy trajectories and the full implementation of pledged climate commitments. These warming levels often deviate from the commonly studied 1.5°C and 2°C benchmarks, highlighting the urgent need for mitigation and adaptation.  

Our results provide a basis for targeted adaptation strategies in Central Europe to mitigate the adverse effects of increasing heat stress. Strategies may include enhancing urban planning to reduce heat accumulation, improving early warning systems, and strengthening healthcare infrastructure to cope with the anticipated rise in heat-related illnesses.