What do warming-adjusted CORDEX RCM projections tell us about climate change in central Europe?

The majority of CORDEX RCMs show an underestimation of historical warming compared to observations, as well as an underestimation of projected warming compared to global climate models. This is in part due to a lack of consideration of changing aerosol concentrations, with a particularly strong effect in Europe leading to a delayed warming. We have developed a new method to address this issue and present the results of the warming-adjusted data. The method adjusts the CORDEX RCM simulations by using a mapping based on large scale warming with only few parameters and minimal interventions, preserving time monotony. The impact of the method is strongest for high emission scenarios but can be demonstrated for all emission scenarios.

An application is shown for a central European region and within this framework we analyze adjusted climate projections. Compared to global climate model experiments, warming-adjusted RCM simulations better capture fine-scale details such as complex orography, yet – by design – feature the same overall temperature evolution across Western Europe. The presented method could also be useful for CORDEX projections for other regions and can provide information for upcoming assessment reports.