Analyzing Extreme Flood Events in a Warming Climate: Insights from High-Resolution Storyline Simulations

Climate change is driving significant changes in the frequency and intensity of extreme hydrological events such as floods and droughts. Events like the 2021 Ahrtal flood, 2010 Pakistan flood, and 2020 Gloria flood underscore the growing vulnerability of regions to these extreme events. Spectral nudging is used to reproduce observed conditions in a climate model system, thus enabling the representation of extreme events in the historical and climate change scenarios. In this study, we utilize high-resolution storyline simulations derived through spectral nudging of the IFS-FESOM global climate model to force the global mesoscale hydrological model mHM (mhm-ufz.org). Currently, the IFS-FESOM storyline simulations operate at a spatial resolution of 10 km and an hourly temporal resolution, thus allowing us to study diurnal variability in the flood events. The first part of this study involves the validation of historic event using observation based datasets like ERA5. In the second part the same event is recreated in a 2K warmer climate. By analyzing the event in a warmer world, this study provides critical insights into regional vulnerabilities and informing adaptation planning and strategies to mitigate the impacts of climate extremes in a rapidly warming world.