Typhoon disaster chain risk assessment: A model based on disaster hazard and carrier vulnerability

The disaster chain caused by strong typhoons has caused huge social economy and ecological environment impact on coastal areas. In this study, a special risk assessment model is proposed for the typhoon-storm tide-flood-embankment disaster chain based on its disaster mechanism and chain disaster law. The proposed model is developed to reflect both the disaster hazard which based on the probability distribution function of Bayesian network, and the carrier vulnerability which based on the evaluation index system. The model has been successfully applied in the coastal cities of Guangdong Province, China, and the disaster chain risk under three typical typhoon scenarios has been simulated. The results reveal that the risk distribution of different disasters caused by typhoons is different due to the different decisive factors. For storm tide disaster, the highest risk is mainly in the coastal city of Zhuhai, and as the influence of sea level increase caused by typhoon gradually weakens from coastal area to inland, the disaster chain risk gradually weakens from coastal to inland. For flood disaster, the highest risk is mainly distributed in the economically developed and densely populated Foshan City due to its low carrier vulnerability. For embankment disaster, the highest risk is mainly distributed in Zhongshan City due to its low design grade of dike, indicating that the condition of water conservancy project is an important factor in determining whether the dike failure or not. The research results are of great significance for coping with typhoon disaster chain in coastal areas, and have certain reference value for identifying the chain risk transmission of typhoon disaster.