Impacts of wind-field correction on the numerical simulation of storm-surge inundation during typhoon “Rammasun”

Accurate wind forcing is an important prerequisite of storm-surge and inundation simulations. However, traditional methods of wind-field improvement, such as an increase in resolution and the assimilation of observations, are difficult to provide because of either computational limitations or the lack of observations, which detracts from the ability to make quick assessments. Therefore, a method for correcting the wind field is developed for low-resolution wind fields, depending on the underlying surface. We investigate the ability of the correction method to simulate storm surge and inundation using the Finite-Volume Coastal Ocean Model (FVCOM), with the Typhoon “Rammasun” as an example. The total elevations, astronomic tides and surges are validated against routine observations, while inundation areas and submerged depths before and after the wind-field correction are compared with the results of field surveys. Corrected wind fields in the harbor and inundated regions significantly increase the simulated water elevations, inundation areas and submerged depths, with the submerged depths being more consistent with observations. Our local wind-field correction method for different underlying surfaces is a simple and effective tool for providing more accurate wind forcing for storm-surge and inundation simulations.