A High Resolution Simulation Of Circulation In The Miyako, Tokara And Osumi Straits

In this paper, the MIT general circulation model, nested grid technique and high resolution grid (1/48°×1/48° in horizontal direction, 22 levels in vertical direction) are adopted to simulate the circulation in Miyako Strait, Tokara Strait and Osumi Strait.The comparison of numerical results based on different resolution shows that the bathymetry has significant influence on the circulation in strait. High resolution model has a good performance in simulating the distribution of velocity core in the top 400m layer, and in reflecting the flow situation in deep layers of strait. Besides, current intensity is more approach to reality in high resolution model.There is a three-level hierarchical structure in vertical direction in Miyako Strait. This agrees well with the results obtained from hydrology and chemical data analysis. In the top 400m layer, the current flows from the Pacific to East China Sea with an average velocity of about 10cm/s. Its max velocity core locates in 160m. In the mid-layer from 400 to 1000m, the current flows from East China Sea to the Pacific with an average speed of about 2cm/s. Its max velocity core locates 650m. In the lower layer deeper than 1000m, the current flows from the Pacific to East China Sea with an average velocity of about 1 cm/s. Its max velocity core locates in the vicinity of 1200m.