Storm Surge Inundation Modulated by Typhoon Intensities and Tracks: Simulations Using the Regional Ocean Modeling System (ROMS)

Storm surges are one of the most severe marine hazards, causing fatalities and devastating infrastructure. It is important to conduct research on storm surge hazards to achieve disaster avoidance and the protection of local populations. In this study, the Regional Ocean Modeling System (ROMS) was used to develop a framework to simulate the inundation (using the wet/dry method) of land in Ningbo, China during an extreme typhoon storm surge. The baseline simulation with the realistic typhoon intensity and track was well validated by meteorological and ocean tidal observations. Using reanalysis and an asymmetric typhoon wind field from the Holland model as atmospheric forcing, we presented different storm surge inundation scenarios regarding various intensities and tracks. The results revealed that typhoon storm surges are significantly affected by both the intensities and tracks of typhoons. Specifically, when Ningbo was located in the navigable semicircle, increasing the typhoon intensity not only resulted in the total inundation area of the whole study area from 108.57 km(2) to 139.97 km(2), but also led to significant negative storm surges in some sea areas. When Ningbo was exposed to the dangerous semicircle of the intensified typhoon, the storm surge along the coast of the Xiangshan Bay could exceed 4 m, amplifying the total inundation area to 245.41 km(2). Thus, it was evident that the location of the impacted region within the typhoon's wind field plays a critical role in determining the severity of the storm surge. These results provide valuable suggestions for storm surge disaster prevention and mitigation for local governments.