【作者】 袁耀初； 刘勇刚； 苏纪兰； 金子新；

【Author】 Yuan Yaochu,Liu Yonggang,Su Jilan,Kaneko ArataSecond Institute of Oceanography,State Oceanic Administration,Hangzhou 310012Key Lab of Ocean Dynamic Processes and Satellite Oceanography,State Oceanic Administration,Hangzhou 310012Hiroshima University,Faculty of Engineering,Higashi-Hiroshima 739

【机构】 国家海洋局第二海洋研究所国家海洋局海洋动力过程与卫星海洋学重点实验室； 日本广岛大学工学部；

【摘要】 基于1997年12月“中日副热带环流合作调查”航次获得的CTD及ADCP测流资料,以及1997年11月至12月日本“长风丸”号调查船在东海获得的CTD资料,分别采用改进逆方法及改进动力计算方法对台湾岛以东黑潮和涡以及东海黑潮进行了计算,获得的主要结果是:(1)在台湾岛东南、巴士海峡附近海域存在一个较强的气旋式冷涡C1,方向自西南向东北,呈舌状.在K0断面东部(约20°N附近)也存在一个冷涡C2,其中心位置约在20°N,124°30’E.(2)黑潮在台湾岛东南通过冷涡C1以东海域,然后作气旋式弯曲.台湾岛以东黑潮分为主流及一个分支,黑潮主流向西北方向流动,最后转为向北,通过与那国岛以西海域进入东海;黑潮的一个分支,其流量不大,并不流向冲绳岛以东海域,而向北通过与那国岛和西表岛之间海域进入东海.(3)该航次黑潮在断面K2的位置在124°E以西,与其他航次时期相比,此时黑潮通过台湾岛东南断面K2的位置明显向东移动.黑潮通过断面K2的北向净流量约为27.6×106 m3/s,与其他航次相比,明显减小.这表明,在1997年冬季出现很强的El Nino现象时,黑潮的强度及流量在台湾岛东南海域明显减小了.(4)在石垣岛、宫古岛及冲绳岛以南海域,存在一个范围较大的反气旋式再生环流,与其他航次相比,范围扩大,它的中心向西移动,约位于24°N,125°-126°E之间.(5)在1997年11月通过东海PN断面的北向净流量约为25.9×106 m3/s.更多还原

【Abstract】 The hydrographic data were obtained from two cruises,viz. a cruise of the China-Japan Joint Investigation on Subtropical Circulation System in December 1997 and another cruise in November - December 1997 by the R/V Chofu-Maru. Using the above data, a modified inverse method and a modified dynamical method both are applied to compute the Kuroshio east of Taiwan Island and in the East China Sea, respectively. It is found that: (1) there is a cyclonic cold eddy C1 with tongue-like from the south west to the northeast,which is located southeast of Taiwan Island and near the Bashi Channel. At the eastern part of Section K0(near 20°N). also there is a cold eddy C2, and its center is located at about 20° N, 124°30’ E; (2) the Kuroshio southeast of Taiwan Island flows east of a cold eddy C1.then it makes a cyclonic meander. There are the main branch of the Kuroshio and its branch east of Taiwan Island.The main branch of the Kuroshio flows northwestward, and finally it turns the north and enters the East China Sea through the area west of Yonakuni-jima. A branch of the Kuroshio does not enter the region east of Okinawa -jima, but it flows nonhward and enters the East China Sea through the channel between Yonakuni-jima and Iriomote-shima, and its volume transport (VT) is not large; (3) the Kuroshio is located west of 124° E at Section K2 in December 1997, i. e., the location of the Kuroshio at Section K2 during this cruise moves eastward as compared with that during other cruises. The northward net VT of the Kuroshio through Section K2 southeast of Taiwan Island is about 27.6×106 m3/s in December 1997. A comparison between the VT of the Kuroshio through Section K2 during this cruise and other cruises is made, and it is found that this value of VT of the Kuroshio decreases obviously.This means VT of the Kuroshio southeast of Taiwan Island decreases obviously in 1997 very strong El Nino year; (4) there is an anticyclonic recirculation gyre in the region south of Iriomote-shima, Miyako-jima and Okinawa-jima, and its scale is larger than that during other cruises, and its center is located at about 24°N, 125°-126°E, i. e., its position moves westward as compared with that during other cruises; (5) the northward net VT through PN in the East China Sea is about 25.9×106 m3/s in November- December 1997.更多还原