Enhanced Role of Convection in Future Hourly Rainfall Extremes Over South Korea

A convection-permitting regional climate model (CPRCM) with 2.5 km resolution has been simulated over South Korea for current and future conditions, and the role of convection in the scaling of hourly extreme precipitation (EP) with temperature is examined. It is found that the CPRCM can reproduce the observed super Clausius-Clapeyron (C-C) scaling for hourly EP. Precipitation type estimated based on the convective available potential energy reveals the important role of convection in the super C-C scaling. Fraction of convective rainfall events increases rapidly with temperature, and the contribution of convection becomes dominant in future simulations under high-emission scenarios. In the late 21st century, as temperature ranges shift to warmer conditions, unprecedented hourly extreme rainfall events are projected to occur particularly during the late summer season. Future changes in hourly extreme events are found to be affected much by boundary conditions from different global climate models.