Flash Flood Risk Assessment and Driving Factors: A Case Study of the Yantanxi River Basin, Southeastern China

Abstract In the context of climate change, impact extreme precipitation and its chain effects has intensified in southeastern coastal region China, posing a serious threat to socioeconomic development region. This study took tropical cyclones–extreme precipitation–flash floods as an example carry out risk assessment flash under change Yantanxi River Basin, China. To obtain flood inundation characteristics through hydrologic–hydrodynamic modeling, combined representative concentration pathway (RCP) shared (SSP) scenarios examine used geographical detector explore driving factors behind change. The results show that Basin will significantly increase, are main forces. Under RCP4.5-SSP2 RCP8.5-SSP5 scenarios, is expected increase by 88.79% 95.57%, respectively. drivers case area GDP density ( q = 0.85), process rainfall 0.74), asset 0.68), population 0.67). highlights influence on disaster small river basins. Our findings also provide reference for regional planning construction control facilities flood-prone areas, which may help reduce floods.