Increasing socioeconomic exposure to extreme tropical cyclone precipitation over China

Abstract This study investigates spatiotemporal changes in socioeconomic exposure to tropical cyclone-induced precipitation (TCP) extremes across China using high-resolution rainfall and gridded population datasets. Results show that extreme TCP exhibits a significant increasing trend over central–southern China, while decreasing trends are observed in parts of the Yangtze River Delta. These contrasting patterns are linked to changes in TC characteristics, including intensified precipitation rates and reduced translation speeds over coastal regions, which enhance rainfall persistence and accumulation and thereby contribute to increasing extreme TCP events inland. Regions with high socioeconomic exposure are mainly concentrated in southeastern and central–eastern China. Based on a modified exposure index that integrates physical hazard and socioeconomic factors, we find that although exposure is jointly determined by these components, its recent increase is primarily driven by intensified TCP intensity and duration, with population growth and economic development further amplifying the impacts. Population and Gross Domestic Product exposure to extreme TCP events (>200 mm) increase by approximately 27% and 17%, respectively, with pronounced spatial heterogeneity. Rapid urbanization and economic expansion in recent decades have further elevated vulnerability to TC-induced precipitation extremes. This multiscale framework provides actionable insights for prioritizing mitigation and adaptation strategies, enhancing climate resilience in high-risk zones.