GIS-based risk assessment of rainstorm and flood disasters in (RFD) Guangzhou

Abstract

Risk assessment of rainstorm and flood disasters (RFD) is an important means to improve the ability of pre-disaster warning and disaster prevention and mitigation in cities. This paper uses the data on the physical geography and socio-economics of Guangzhou to construct an assessment system from four aspects: hazard-causing, disaster-pregnancy, disaster-bearing, and disaster-resistance. The weighted comprehensive analysis method and GIS software are used to spatially analyze and validate Guangzhou's heavy rainfall and flooding risk. The results show that the hazard of the disaster-causing factors tends to increase from west to east, the sensitivity of the disaster-pregnant environment generally shows a distribution pattern of being low in the north and high in the south, and the areas with the high vulnerability of the disaster-bearing bodies are mainly concentrated in the central city of Guangzhou and other areas with high population density and high economic development level. Overall, the comprehensive risk of RFD in Guangzhou is irregularly distributed spatially. The high risk or secondary high risk are mainly located in areas with a high hazard of disaster-causing factors, high sensitivity of disaster-pregnant environment but limited disaster-resistance capacity, or high sensitivity of disaster-pregnant environment and vulnerability of disaster-bearing bodies.