Numerical Simulation Of The Tides And Currents In The East China Sea

East China Sea has the obvious features of the circulation, which can affect the state of the marine environment, as well as the transport of matter and energy. At the same time, the circulation can also affect local air-sea interaction or even the regional climate changes. Therefore, the studies on the circulation characteristics attract more attentions from the oceanography or meteorology all the time. Because of the lack of the long-term and systemic observations, the numerical model has been an important tool in the oceanography or meteorology researches in recent several decades.Based on the Princeton Ocean Model (POM), we first simulated the main features of the semidiunal and diunal (M2, S2, K1, O1) tides in the East China Sea using Nao.99Jb data. Three barotropic open boundary conditions, clamped elevation, clamped normal velocity and Flather were selected on the model simulations, based on which the simulation ability of POM in East China Sea is also investigated. Then, using the SODA, Marine Atlas of the Bohai Sea, Yellow Sea, and East China Sea data and LEVITUS94 data, we simulate the winter circulation fields and discuss the impacts of wind stress on different ocean currents in East China Sea under three-dimensional baroclinic condition.The simulation results indicate that the POM is available in the high-resolution simulations of East China Sea tide and circulation. However, to avoid the errors resulting from the density computation, the adjustment of the topography where has high gradient in deep ocean is needed. The simulation results also indicate that the Flather open boundary condition is better to simulate the complex topography tide when compared with the other two boundary layers in the barotropic condition. When compared with the station observations, the average error of simulated amplitude and phase of the M₂ constituent are 5.62cm and 7.90°, respectively. Furthermore, the three-dimensional barocline results show that the Taiwan, Tsushima and Huanghai warm currents have the "multi-source" structure and the Kuroshio has an important effect on them. Additionally, the simulations indicate that the winter sea surface wind stress has so important impacts on East China Sea circulation that it can promote the initiation of the coastal current there and force it intensively to the Fujian and Zhejiang coast, thus, the coastal current show the significant characteristics of the wind-driven current.