Predicting Changes in Population Exposure to Precipitation Extremes over Beijing–Tianjin–Hebei Urban Agglomeration with Regional Climate Model RegCM4 on a Convection-Permitting Scale

In this study, we have investigated changes in precipitation extremes and the population’s exposure to these during 2091–2099 China’s Beijing–Tianjin–Hebei (JJJ) region relative historical period of 1991–1999. First, regional climate model RegCM4, with a hydrostatic dynamic core, was run for east Asia, including China, at 12 km resolution 1990–1999 2090–2099. This is forced by global (GCM) MPI-ESM1.2-HR under middle shared socioeconomic pathways (SSP245). The first year used as spinup. Then, results were force RegCM4 non-hydrostatic core (RegcM4-NH) 3 convection-permitting scale over JJJ future periods. Future predicted increase whole China its four subregions, while decreases region. may partly be caused lower increases specific humidity percentage contributions three components total population exposure, i.e., due population, joint impact extremes, then analyzed. Changes wet closely related dominant factor that most impacts dry extremes. Finally, per degree warming quantified