Projection of disaster-causing risk of extreme precipitation in the Yangtze River Basin based on CMIP6

Abstract

Global warming will significantly affect the frequency and intensity of extreme precipitation and further affect the spatio-temporal pattern of disaster-causing risk of extreme precipitation. This study analyzes the spatio-temporal trends of extreme precipitation and projects its disaster-causing risk under different climate scenarios in the Yangtze River Basin from 2021 to 2100. The results indicate that the extreme precipitation in the Yangtze River Basin shows an increasing trend in the future. Annual precipitation (PRCPTOT) increases by 33.05–42.56% under five scenarios compared with the historical period. The future change in heavy precipitation (R95p) also shows a significant increase, but heavy rain days (R50) and 5-day maximum precipitation (RX5day) decrease. The disaster-causing risk of extreme precipitation in the Yangtze River Basin is mainly Levels III and IV, accounting for 57.23–65.99% of the total basin area. The area with Level V is mainly distributed in the Poyang Lake Basin and the lower main stream of the Yangtze River. Moreover, the changes in disaster-causing risk of extreme precipitation are mainly manifested in the decrease of areas with low risk (Levels I and II) and the increase of areas with medium risk (Levels III and IV) in different periods. HIGHLIGHTS An assessment model of the disaster-causing risk of extreme precipitation was established.; All indices of extreme precipitation present a fluctuating upward trend in the future.; The distribution of disaster-causing risk in the Yangtze River Basin is mainly in Levels III and IV.; The spatio-temporal pattern of risk levels is attributed to the changes in extreme precipitation.; Poyang Lake Basin has the highest risk in the future.;

Keywords

• cmip6
• disaster-causing risk
• extreme precipitation
• the yangtze river basin