| China is a country that suffers frequently from storm surges. In the coastal area of the Bohai Sea and the northern Yellow Sea, the storm surge can be induced by tropical cyclones or extratropical cyclones. In the near-shore area, wave and storm surge can coexist and interact with each other, a good understanding of these two processes and their interaction is very important for the numerical simulation, prediction and warning of storm surge. Based on the research of the interaction of wave and storm surge, the influence of wave on the storm surges induced both by tropical cyclone and extrotropical cyclone in the Bohai Sea and the Yellow Sea was studied in this paper.Based on the former algorithm of the wave-dependent surface wind stress, wave-induced radiation stress and wave-dependent bottom stress, the three- dimensional current model POM and the third generation shallow water wave model SWAN were used to simulate the storm surges occurred in the Bohai Sea and the Yellow Sea under two kinds of typical weather conditions. The wave influence on storm surges was discussed in detail.Experiments were made with only one aspect of the wave influence taken into consideration in the simulation of storm surge, and the results were compared with that of the pure storm surge.Compared with the pure storm surges, when only the wave-dependent surface wind stress was considered, the simulation results showed that it has a remarkable influence on storm surge both induced by tropical cyclone and the extratropical cyclone. When the storm surge caused a water level rising, the wave-dependent stress could increase the rising and when a water level drop happened, the wave-dependent wind stress would enlarge the drop. For the storm surge induced by tropical cyclone, the main effects of the wave-dependent wind stress focused on the peak values, the maximum relative variety was 25.95%. while for the one induced by extratropical cyclone, the wave-dependent wind stress could influence the water level in the whole process. At the peak values, the maximum relative variety was 41%.Compared with the results of pure storm surge, when the wave-induced radiation stress was considered, the simulation results showed that wave modulation was not significant, and the maximum modulation was no more than 6% for the storm surge induced by tropicsl cyclone. For the storm surges induced by extratropical cyclone, the influence of wave-induced radiation stress is basically negligible.The results just considering the wave-dependent bottom stress showed that when the water level was rising, the wave-dependent stress made the surface higher, while when the water level was descending, the wave-dependent bottom stress resulted in a larger drop. For the storm surge induced by tropicsl cyclone and extratropical cyclone, the maximum modulation caused by the wave-dependent bottom stress at the peak level was 12% and 9% respectively. The effects become more obvious as the water got shallower where the surge level was higher.As a whole, the wave influences the storm surge through the surface wind stress, radiation stress and bottom stress among which the wave-dependent wind stress played the most significant role, the bottom stress takes the second place, the radiation stress influence is least significant. Compared with the observation, the result taking the wave influence into consideration in the simulation gave a significant improvement, especially at the peak points, where the simulation considering the influence of wave was closer to observation, suggesting the necessity of considering the influence of wave in the storm surge simulation. The wave influence must be taken into consideration in the storm surge numerical simulation.
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