Evaluation of regional climate models at multi-decadal time periods and across spatial scales in the European Alps

Mountain regions are especially sensitive to climatic changes. The complex local topography modulates meteorological and climatic patterns and simultaneously creates challenges in modeling and observing local-scale features. In this study, we present an extensive evaluation of an ensemble of regional climate models (RCMs) from EURO-CORDEX and bias adjusted simulations from CORDEX-Adjust, both at 12 km resolution, for the European Alps. These are compared with two higher resolution simulations from convection-permitting models at 4 and 2 km. The evaluation focuses on elevation-dependent biases in temperature and precipitation and multi-decadal time periods. We use APGD and EOBS as reference observations in addition to high-resolution national datasets. Preliminary results show a large variation in the RCMs’ capability to match observed temperature and precipitation elevation gradients, while bias adjustment can remove the overall cold and wet bias of the 12km RCMs in the Alps. Our results inform the application of both raw and bias-adjusted RCM simulations for impact analyses in the complex Alpine terrain. They furthermore provide a reference for the evaluation of upcoming CMIP6-based RCM ensembles at convection-permitting and conventional resolution.