Hazard Assessment of Typhoon on the Southeast Coast of China Using Grid Fixed-point Method

Typhoon hazard assessment is the basis of loss estimation and disaster prevention and mitigation. This study investigates the use of grid fixed-point method to assess typhoon hazards. We conduct experiments on the southeast coast of China based on site data. In this paper, we first divided this study area into 0.25°×0.25° grids by using the grid fixed-point method, and perform wind field simulation using each grid center point as the study point based on typhoon tracks data of the 1960-2019 years. Next, we perform 50 and 100-year wind speed estimation of the return period by constructing the 60-year wind speed extreme value sequence of the grid center point and using the extreme value distribution function. At last, we implemented the discussion regarding spatial distribution characteristics of typhoon disasters. Our results show that the wind speed changes greatly and shows a certain gradient change in the near coastal areas. Moreover, we can see that wind speeds began to weaken rapidly near inland, reaching a plateau in inland. Furthermore, island has a higher wind speed compared with other areas. We can conclude that the proposed methods have a high potential for assessing typhoon hazards from site data.