Convection‐permitting dynamical downscaling of ERA5 for Europe and the Mediterranean basin

Abstract As the European continent and the Mediterranean Sea experience rapid warming trends and diverse manifestations of extreme weather, there is an urgent need to understand and mitigate the impacts of climate change in these regions. This study introduces the Computational Hydrometeorology with Advanced Performance to Enhanced Realism (CHAPTER) high‐resolution dynamical downscaling of the European Centre for Medium‐Range Weather Forecasts Reanalysis v5 (ERA5) global reanalysis made with the Weather Research and Forecasting numerical model. CHAPTER covers Europe and the Mediterranean basin at a convection‐resolving grid resolution of 3 km by 3 km. CHAPTER's performances in representing precipitation and temperature are evaluated compared to state‐of‐the‐art datasets like ERA5‐Land. The focus is put on seasonal spatial distributions of the bias and the root mean square error, and fuzzy verification techniques are used to validate the precipitation outputs. The results reveal that CHAPTER's performance aligns closely with well‐recognized downscalings of ERA5 but has, in addition, the advantage of providing a rich portfolio of variables at hourly temporal resolution and on different terrain, following model levels. Therefore, CHAPTER is a valuable resource for studying extreme weather events, offering insights crucial for climate change adaptation and mitigation efforts in Europe and the Mediterranean region.