Convection-permitting Simulations of Current and Future Climate over the Tibetan Plateau Region

The Tibetan Plateau (TP), known as Asian Water Tower, provides a vital water resource for the downstream regions. Previous studies of water cycle changes over the TP have been conducted with climate models of relatively coarse resolution, leading to potential misrepresentation of key physical processes. In this study, we presents results from a high resolution climate change simulation that permits convection at about 4-km grid spacing with focus on the TP region using the Icosahedral Nonhydrostatic Weather and Climate Model (ICON). Two 12-year simulations were performed, consisting of a retrospective simulation (2008-2020) with initial and boundary conditions from ERA5 reanalysis and a pseudo-global warming projections driven by the modified reanalysis-derived initial and boundary conditions through adding the monthly CMIP6 ensemble-mean climate change under SSP5-8.5 scenario. The retrospective simulation shows overall good performance capturing the annual/seasonal/sub-seasonal precipitation and surface temperature. The future climate simulation suggests that the TP will be wetter and warmer under SSP5-8.5 scenario. The ICON-downscaled climate change simulations provide a high-resolution dataset to the community for studying regional climate changes and impacts over TP.