Delivering an Improved Framework for the New Generation of CMIP6-Driven EURO-CORDEX Regional Climate Simulations

Abstract

Abstract The Coordinated Regional Downscaling Experiment (CORDEX) is a coordinated international activity that has produced ensembles of regional climate simulations with domains that cover all land areas of the world. These ensembles are used by a wide range of practitioners that include the scientific community, policymakers, and stakeholders from the public and private sectors. They also provide the scientific basis for the Intergovernmental Panel on Climate Change-Assessment Reports. As its next phase now launches, the CMIP6-CORDEX datasets are expected to populate community repositories over the next couple of years, with updated state-of-the-art regional climate data that will further support national and regional communities and inform their climate adaptation and mitigation strategies. The protocol presented here focuses on the European domain (EURO-CORDEX). It takes the international CORDEX protocol covering all 14 global domains as its template. However, it expands on the international protocol in specific areas; incorporates historical and projected aerosol trends into the regional models in a consistent way with CMIP6 global climate models, to allow for a better comparison of global versus regional trends; produces more climate variables to better support sectorial climate impact assessments; and takes into account the recent scientific developments addressed in the CORDEX Flagship Pilot Studies, enabling a better assessment of processes and phenomena relevant to regional climate (e.g., land-use change, aerosol, convection, and urban environment). Here, we summarize the scientific analysis which led to the new simulation protocol and highlight the improvements we expect in the new generation regional climate ensemble.