Wind disaster assessment of landfalling typhoons in different regions of China over 2004–2020

Abstract

In this study, the wind disasters caused by typhoons that have led to landfall in China during 2004–2020 were investigated using the radial integral method of wind disaster assessment. The typhoon parameters were mainly obtained from China Meteorological Administration. Results from the Joint Typhoon Warning Center and Japan Meteorological Agency were also used as supplements to test the integrity, authenticity, and validity of the data. First, the two factors that influencing typhoon wind disasters, namely, typhoon intensity and spatial scale, were analyzed. The intensity of typhoons and the overall spatial scale were found to weaken and decrease, respectively, after landfall. Second, the applicability of the radial integral typhoon wind disaster assessment method to scenarios involving actual typhoons was verified for the first time using existing typhoon wind disaster measurement data. Furthermore, the radial integral method was used to study the change regularity of typhoon wind disasters before and after landfall in different regions of China. The wind disaster weakening of landfalls in the mainland was significant compared to that in islands. After a landfall on an island, wind disaster attenuated to 73.91% and 75.50% of the value before landfall. This result is consistent with the results obtained for hurricanes in the Northwest Pacific in previous years. Landfalls in mainland typhoon wind disasters attenuated to 54.38%. This result is consistent with the current results of hurricanes in the Northwest Pacific. This is because of the reduction in the attenuation rate after typhoons or hurricanes landfall due to changes in global climate and urbanization. However, the impact on island regions is smaller. The results of this study can facilitate the rapid assessment of typhoon wind disasters and can serve as guidelines for preventing typhoon wind disasters in inland impacted regions. Thus, this study contributes toward disaster prevention and mitigation in coastal areas, urban areas, and offshore wind farms.