Variability of the Kuroshio in the East China Sea in 1992

Based on the hydrographic data of the four cruises in 1992,a modified inverse method is used to compute the velocity,volume and heat transports of the Kuroshio in the East China Sea.The computed results show that:(1)There are two current cores of the Kuroshio at Section PN in spring and autumn,but one core in winter and summer.The main core always lies over the shelf break.The Kuroshio is strongest in spring.secondary in winter and summer and weakest in autumn.There are also countercurrents under and east of the Kuroshio at Section PN.(2) There are two current cores of the Kuroshio at Section TK in winter,three cores in spring and summer.Countercurrent,exist in the southern part and the deep layer of the Tokara Strait.(3) The Tsushima Warm Current(TSWC)at Section A is strongest in autumn and weakest in winter,and is stronger than the Huanghai Warm Current which lies to the west of the TSWC.(4)The net northeastward volume transport (hereafter VT) through Section PN is largest in summer and,mallet in autumn with an average of 28.0×10⁶m³/s in the four cruises of 1992.the net eastward VT at Section TK is also largest in summer.The net northward VT at Section A is largest in autumn.(5) The average heat transport through Section PN during the four cruises is 2.03×10¹⁵ W,and that through Section TK is 2.00×10¹⁵ W during the three cruises.(6) In the computation area,heat transfer is from the ocean to the atmosphere during winter.spring and autumn,but from the atmosphere to the cxean in summer.The average rate of heat transfer is largest in winter,but smallest in summer.