Numerical Simulation And Dynamic Mechanism Research Of Wintertime Circulation Of East China Seas

Based on MOM2 model, a 3-dimentional prognostic baroclinic Z-ordinate model was established to study the circulation of East China Seas, considering the real topography, inflow and outflow on the open boundary, wind stress, temperature and salinity exchange on the sea surface. The results are consistent with observation. The results show that Kuroshio intrudes onto the continental shelf of East China Sea in large scale and during its flow water is exchanged ceaselessly with outer sea along Ryukyu Island. Tsushima Warm Current derives from several sources, includes a branch of Kuroshio, part of Taiwan Warm Current and Yellow Sea mixed water coming from the west of Cheju Island. The water from the west of Cheju Island approximately contributes 13% of total transport of Tsushima Warm Current through Korea Strait. The circulation in Bohai Sea and Yellow Sea is basically of cyclone shape comprising the coastal currents and the Yellow Sea Warm Current. Besides the real circulation simulation, numerical experiments were done to study the dynamic mechanism. The numerical experiments indicate that the wind directly drives the East China Sea and Yellow Sea Coastal Current, it strengthens both the Korea Coastal Current and Yellow Sea Warm current. In no wind case, the kinetic energy of the coastal current area and main YSWC area is only 1% of that of wind case. Numerical experiments show Tsushima Warm Current is of greatimportance to the formation of the Korea Coastal Current and Yellow Sea Warm Current. Topography also influence coastal currents and circulation in Bo Sea.