1992年东海黑潮的变异

Variability of the Kuroshio in the East China Sea in 1992

基于1992年4个航次的水文调查资料，运用改进逆方法计算了东海黑潮的流速、流量和热通量．计算结果表明：（1）PN断面黑潮在春季和秋季都有两个流核，冬季和夏季则只有一个流核．主核心皆位于坡折处．Vmax值春季最大，冬季和夏季次之，而秋季最小．黑潮以东及以下都存在逆流．（2）TK断面黑潮在冬季为两核，春、夏季为3核．海峡南端及海峡深处存在西向逆流．（3）通过A断面的对马暖流Vmax值在秋季最大，冬季最小．黄海暖流位于其西侧，相对较弱．（4）通过PN断面净北向流量夏季最大，秋季最小，而冬、春季介于上述二者之间，1992年四季平均值为28．0×106m3/s；TK断面的净东向流量也是在夏季最大；A断面净北向流量则在秋季最大．（5）PN断面4个航次的平均热通量为2．03×1015W．TK断面3个航次的平均热通量为2．00×1015W．（6）在计算海区，冬、春和秋季都是由海洋向大气放热；夏季则从大气吸热．冬季海面上热交换率最大，而夏季热交换率最小．关键词##4东海;;黑潮;;

──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. Countercurrents 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 smallest in autumn with an average of 28. 0×106 m3/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 ocean in summer. The average rate of heat transfer is largest in winter, but smallest in summer.