Northeast Of Taiwan And The Luzon Strait, The Kuroshio Hydrological Dynamics Analysis

A streamfunction projection method called Geostrophic Empirical Mode (GEM) is used to diagnose the historical hydrographic data in the Kuroshio northeast of Taiwan. By examining the spatial and seasonal variations of the GEM fields, we find that the Kuroshio Shallow Water (<300m) in the Okinawa Trough is fresher and colder than that south of the Su-Ao Ridge. It provides evidence that the returning branch of the cyclonic cold eddy north of Taiwan exerts a strong influence on the water properties in the southern Okinawa Trough. Meanwhile the Kuroshio Deep Water (>1000m) is comparatively fresher and warmer within the Okinawa Trough, reflecting the topographic blocking on the Kuroshio deep water mass by the ridge. The study also reveals a regional salinity maximum of the Kuroshio Intermediate Water (KIW) in the southwestern corner of the Okinawa Trough, which we hypothesize is the result of the intensive mixing in the confluence region between the Kuroshio and the perennial cold eddy. And this methord is also used to diagnose the historical hydrographic and Argo data in the Luzon Strait Kuroshio. By using the Satellite Altimeter and Drifter data ,we explain the phenomenon that Kuroshio Surface Water intrudes into the SCS.