Spatial–temporal assessment of future extreme precipitation and extreme high-temperature exposure across China

This study utilizes climate scenario data from the Coupled Model Intercomparison Project Phase 6 (CMIP6) and population gridded data from shared socioeconomic pathways (SSPs) to identify extreme precipitation and high-temperature events, along with their impact on the population in China and its subregions for both the near-term future (2020–2050) and the long-term future (2070–2100). The precipitation and temperature extremes in China are expected to increase during 2020–2100, and they will increase continuously with increasing radiative forcing. The spatial pattern of increases is similar across all SSPs-RCPs scenarios, with a larger rise in the southern study area. Population exposure to extreme precipitation in China is anticipated to rise from 2020 to 2050 and decline from 2070 to 2100 under all scenarios, with a more pronounced decrease in SSP4-6.0, and there is a transmutation in the chief determinant of populace vulnerability to extreme precipitation, transitioning from factors contingent upon population to those contingent upon climate from 2020–2050 to 2070–2100. In addition, temperature exhibits a general increasing trend in the impact area and population exposure from 2020–2050 to 2070–2100, concentrated in eastern and southern China. The exposed population's high-value areas will continually expand with rising radiation forcing. Factors influencing population exposure to extremely high temperatures from 2020 to 2100, including climate, population, and their interaction, exhibit stable contribution rates, with population remaining the dominant factor.