We focused the core of the Kuroshio, the maximum speed in 47m deep. The time series of the latitude and Kuroshio speed are shown in Fig. 4. The mean speed of the Kuroshio was 106cm/s and its standard deviation was 28cm/s. Composite features show that the speed of Kuroshio core when it existed in southern path (112cm/s) was greater than that when it existed in northern path (101cm/s). The difference was about 10% of the mean flow. It is shown in Fig. 5 that there is relationship between the latitude and the speed of the Kuroshio core. Thus there seems interannual signal associated the Kuroshio position variation.
