A coupled numerical model with a 1"×1" resolution grid has been developed and used to simulate two typical typhoon storm surges in the Bohai Sea of China. Three main driving forces have been considered in this coupled model: wave radiation stress, combined wave-current bottom shear stress and wave-state-dependent surface wind stress. This model has then been compared with in situ measurements of the storm set-up. The effect of different driving force components on the total storm surge has also been investigated. This study has found that the coupled model with high resolution is capable of simulating the two typical typhoons better than the uncoupled models, and that the wave dependent surface wind stress plays an important role in typhoon storm surge-wave coupling in this area. The study has shown that the general coupling effects could increase storm set-up by 2–8%. Thus, it is suggested that to predict typhoon storm surges in the Bohai Sea of China, a storm surge-wave coupled model should be adopted.
The generation of waves and storm surges is closely related, as they are both generated by the wind. There exist strong nonlinear interactions between waves, tides and storm surges in shallow water. These mechanisms include mainly the wave-state-dependent surface wind stress, the wave-current interaction bottom stress, and the radiation stress. In the past 20 years, various studies including of: Mastenbroek et al.(1993) coupled a third-generation ocean wave model with a two dimensional storm surge model in which only the wave has effects on currents and not vice versa.; Davies et al.(1994), used a three dimensional hydrodynamic model involving a flow-dependent eddy viscosity and including enhancements of bottom friction due to wave current interaction in shallow water, but not consider the interaction between air and sea.