Simulation of storm surge inundation under different typhoon intensity scenarios: Case study of Pingyang County, China

Abstract. China is one of the countries that are most seriously affected by storm surges. In recent years, storm surges in coastal areas of China have caused huge economic losses and a large number of human casualties. Knowledge of the inundation range and water depth of storm surges under different typhoon intensities could assist pre-disaster risk assessment and making evacuation plans, as well as provide decision support for responding to storm surges. Based on historical typhoon-induced storm surges in the study area of Pingyang County in Zhejiang Province, China, key parameters including typhoon tracks, radius of maximum wind speed, astronomical tide, and upstream flood runoff were determined for different typhoon intensities. Numerical simulations were conducted using these parameters to investigate the inundation range and water depth distribution of storm surges in Pingyang County under five different intensity scenarios (915, 925, 935, 945, and 965 hPa) with consideration of the impact of seawall collapse. The simulation results show that the range of storm surge inundation expands with increasing typhoon intensity. The scenario with the most intense typhoon (915 hPa) had the most adverse track, with an associated area of inundation of 233 km2 that included most areas of the town of Aojiang, eastern areas of Wanquan, northern areas of Songbu, as well as parts of Kunyang and Shuitou.