Variabilities of the sea level anomalies in the upstream areas of the Kuroshio Current

Abstract

The relationship between The Kuroshio velocities and Sea Level Anomalies (SLA) in the upstream areas (between Taiwan and Yonaguni Island) is investigated based on satellite altimetry observation. Mean of the SLA data from 2005-2008 show that in the northeast of Taiwan tends to form strong eddy activity. Furthermore, the type of eddy that forms in the upstream areas is difference every season, cold (warm) eddy more exists in summer (winter). The speed of the Kuroshio in the upstream areas is determined by combination of High- Frequency (HF) radar and Copernicus Marine Environment Monitoring Service (CMEMS) data. These two are exhibited that Kuroshio speed become faster (slower) in summer (winter). High positive correlation of the Kuroshio speed and SLA are found in between Yonaguni and Iriomote Island. When the Kuroshio speed in the middle of HF radar areas (123.375° N) became faster, it coincided with transition of warm eddy to cold eddy in the northeast of Taiwan and vice versa.