Study of the warm Kuroshio Current intruding into the cold Zhemin Coastal Currents through multidiscipline approach including satellite, mooring, and shipboard profiling data

Literatures have well documented the intrusion of the Kuroshio Current into the continental shelf in the southern East China Sea since 1992. However, there is no any report indicating that the Kuroshio Current can intrude into the nearshore of the China coast and influence the coastal currents originating from the Yangtze River. This study combined the field observation and satellite data to present the processes and dynamics between two current systems in winter. The T-S diagram indicated that the warm Kuroshio water originated from the Kuroshio Intermediate Water which is from the Okinawa Trough at the depth around 500 m. The mooring and profiling data revealed that the warm Kuroshio Water wedged under the cold coastal currents in the neap tide but two current waters well mixed vertically in the spring tide. The sea surface temperature in the satellite data presented that the area of the mixing water was more than 20 thousand km². The monsoonal winds were also a key factor influencing the Kuroshio Current intrusion but we didn’t have enough wind field data yet. According to the field data, the interaction between the Zhemin Coastal Currents and the Krushio Current were complex. We believe that it is necessary to integrate the spatial and temporal data for understanding the mixing mechanism in the two current systems.