Parameterization of Wind Stress in Coastal Strong Wind Conditions and Its Application in Storm Surge and Wind-Wave Simulations

Abstract Accurate wind stress parameterization is essential for simulating coastal ocean dynamics. In operational models, wind stress is typically represented by a bulk formula involving a drag coefficient and wind speed. However, conventional drag coefficient formulations, generally expressed as linear functions of 10-m wind speed, suffer from dimensional inconsistency and exhibit substantial variability across observational datasets. In this study, we develop a dimensionally consistent drag coefficient parameterization for coastal strong wind conditions, integrating measurement height, peak wavelength, and wave steepness. Evaluations using three coastal datasets demonstrate that that the wave steepness–based formulation offers improved consistency and predictive skill over traditional wind speed–based and wave age–based approaches. The parameterization is applied in the simulation of storm surge and wind waves during Typhoon Muifa (2022) in the East China Sea. Compared to default wind speed–dependent schemes, the new formulation efficiently improves the simulation of large storm surge heights and significant wave heights.