Applying Risk Analysis to the Disaster Impact of Extreme Typhoon Events Under Climate Change

Abstract

Extreme typhoon precipitation events frequently have a socioeconomic impact and result in the loss of human life. Therefore, conducting thorough evaluations of the disaster scale before the occurrence of extreme typhoon precipitation events is beneficial to disaster reduction. This study selects the Tsengwen River basin, Taiwan, the area most severely impacted by typhoon Morakot, as a demonstration area, and adopts dynamical downscaling data to simulate the top ten extreme typhoon precipitation events of the future (from 2069 to 2099) under climate change. The SOBEK model (commercial software) and the Taiwan Typhoon Loss Assessment System (TLAS), established by the National Science and Technology Center of Disaster Reduction (NCDR), are used to evaluate the potential losses resulting from the ten extreme events. The results indicate that the average total loss caused by the ten simulated typhoon events amounts to US$439 million, with agriculture, followed by aquaculture and forestry, suffering the greatest damage. A correlation analysis is also employed to identify key factors that influence loss, including the maximum 6-hour cumulative precipitation, the maximum peak runoff, and the use of the land. Based on these analysis results, this study provides applicable coping strategies that will effectively reduce the impact of future extreme precipitation events in the Tsengwen River basin.