Stormy Waves Forecast By Wave-current Coupled Model

Development and utilization of marine resources has been a trend, for my country, the development and utilization of this vast storehouse of the South China Sea is the inevitable choice. The area of South China Sea is about 3.5 million square kilometers, however lack of observed data. Forecasting typhoon waves in the South China Sea is particularly important. In previous studies, scholars usually predicted it based on the wave model of SWAN, considering the interaction of waves and currents, based on the actual terrain of the South China Sea and the Taiwan Strait as well as the real monsoon and typhoon wind field, occurred in the South China Sea and the Taiwan Strait area of the storm were estimated.Being compared to the wave-induced current model of classical physics experiment by Hamm, results show that the coupling model is reliable. In this paper, a FVCOM model is utilized to construct a hydrodynamic model in the South China Sea. The simulation results agreed well with observation data. According to the simulation results, the tide and tidal currents characteristics of M2, S2, K1,O1 were analyzed, by this way a dependable water forced boundary is provided. Utilizing the coupled model, Kai-Tak and a monsoon storm were calculated. After comparison with the uncoupled model and measured, data, the results of the coupled model are consistent with the measured results. In coupled model wave time step is usually set to about 1 min, calculation takes a long time however, the simulation of wave height on the overall distribution is similar between coupling model and non-coupled model. In most cases, the using of SWAN is feasible. Difference between significant wave height simulated by uncoupled and coupled model was used to analyze the spatial distribution of wave-current interactions on wave height. For monsoon storms results simulated by uncoupling are usually smaller. For the typhoon wave, the results simulated are changed based on the center of the typhoon.