Risk assessment for typhoon storm surges using geospatial techniques for the coastal areas of Guangdong, China

Typhoon storm surge (TSS) frequently affects the coastal areas of Guangdong Province, causing casualties, severe economic losses, and environmental damage. A risk assessment model using geospatial techniques combined with a fuzzy complete evaluation principle and coupling coordination method to quantify risk in 14 coastal cities of Guangdong was developed to identify significant risk zones, and targeted disaster prevention strategies were proposed. Four major risk systems were established to obtain the spatial distributions of hazards, exposure, sensitivity, and mitigation capabilities. A TSS risk distribution map was generated based on the interactions between risk systems, and dominant risk factors for different regions were identified. The results showed that the very-high risk zone covered 19.40% of the study area, concentrated in the coastal areas of Zhanjiang, Maoming, and Shanwei. The high-risk zone that accounted for 19.94%, was distributed across the very-high risk zone and encompassed cities such as Maoming, Jiangmen, and Yangjiang. The middle-risk zone accounted for 20.93%. In comparison, the central and inland areas of Guangdong were characterized by low risk and very-low risk. To reduce risk, the top priority should be improving mitigation capacity, especially in the coastal regions of Zhanjiang, Shanwei, and Jieyang. In addition, authorities in Maoming need to reduce the exposure of disasterbearing bodies, and government officials in Shantou should take measures to avoid aquaculture development in susceptible areas. The results of this study can be used by the relevant authorities to formulate effective disastermitigation plans and allocate emergency supplies.