Variability of the Kuroshio in the East China Sea during El Nino to La Nina phenomenon of 1997 and 1

Modifed inverse and dynamic methods are used to compute the velocity and volume transport (VT) of the Kuroshio in the East China Sea, based on CTD data obtained between 1997 and 1998. When the El-Nino phenomenon occurred in May of 1997, the VT of the Kuroshio and the average VT of the Kuroshio decreased in the summer of 1997. There are two different current patterns of circulation in the East China Sea for January and June-July of 1997, and these occurred before and after El-Nino phenomenon, respectively. The Kuroshio through section PN was charactersied by multi-current cores between April to November 1997, and in particular, there were three current cores in October and November of 1997. The position of the main current core of the Kuroshio moves eastward during autumn. Both 1995 and 1998 are anomalous years for the Kuroshio in the East China Sea. This may be due to: (1) increase of the Kuroshio VT may be associated with strengthening of the anticyclonic recirculating eddy south of Okinawa; (2) transformation from El-Ni~no to La-Nina phenomenon occurred during the summers of 1995 and 1998.