【作者】 袁耀初； 王惠群； 刘勇刚； 苏纪兰； 金子新；

【Author】 Yuan Yaochu,Wang Huiqun,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 310012Department of Environmental Sciences, Faculty of Engineering, Hiroshima University, 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； 广岛大学工学部；

【摘要】 基于1997年7月“中日副热带环流合作调查”航次获得的水文和风场资料,采用σ坐标系下三维非线性的诊断、半诊断及预报模式,计算台湾岛以东环流及涡旋,并与1995年10月及1996年5-6月台湾岛以东环流特性作了比较,表明诊断、半诊断以及预报三个计算的结果,在定性上是一致的,但在定量上存在一些差别.这三个计算结果是:(1)台湾岛以东黑潮首先向东北向流动,然后作气旋式弯曲转为北向,黑潮的最大流速在诊断、半诊断及预报计算的结果分别为147.4,164.9及164.6 cm/s,都位于表层,表明半诊断及预报计算的结果都显示黑潮的流速增大;(2)比较1995年10月及1996年5-6月黑潮通过台湾岛东南K2断面的流量,发现1997年7月黑潮通过K2断面的流量明显减小,表明1997强厄尔尼诺年黑潮在台湾岛以东流量明显地减小;(3)三种计算结果都表明,在黑潮以东存在一个反气旋式涡W1,在反气旋式涡W1以东存在一支南向流,而在南向流以东则存在一个气旋式冷涡C1,但与诊断计算结果相比较,在半诊断计算及预报计算中,这两个涡W1及C1的位置都要偏南;(4)在计算海区的东北部,即宫古岛及冲绳岛以南海域,存在一个反气旋式再生环流;(5)在黑潮以下存在南向逆流.更多还原

【Abstract】 On the basis of hydrographic data obtained in July 1997 the three-dimensional and nonlinear diagnostic, semidiagnostic and prognostic models in the σ coordinate are used to compute the circulation east of Taiwan Island. Comparing the results of diagnostic calculation with those of semidiagnostic and prognostic calculations, they are qualitatively coincident and there are some differences between them in quantity.The computed results of these three calculations show that: (1) the Kuroshio east of Taiwan Island flows northeastward, then makes a cyclonic meander and turns to flow northward. Its maximum velocity is 147.4, 164.9 and 164.6 cm/s at the surface, respectively, for results of the diagnostic,semidiagnostic and prognostic calculations.This means that the Kuroshio east of Taiwan Island is strengthened for the semidiagnostic and prognostic calculations; (2) in comparison with the volume transport (VT) of the Kuroshio through Section K2 southeast of Taiwan Island during October 1995 and May-June 1996, the value of VT of the Kuroshio through Section K2 southeast of Taiwan Island decreases obviously during July 1997, i. e., the VT of the Kuroshio southeast of Taiwan Island decreases obviously during the 1997 stronger El Nino year; (3) there are an anticyclonic eddy W1 east of the Kuroshio and a southward flow east of an anticyclonic eddy W1 ,and a cold eddy C1 east of a southward flow, respectively, for these three calculations.However the positions of these two eddies W1 and C1 both move southward for the semidiagnostic and prognostic calculations, comparing with the result of diagnostic calculation; (4)an anticyclonic recirculation gyre appears in the region south of Miyako-jima and Okinawa-jima and in the northeastern part of computational region; (5) there is a southward countercurrent below the Kuroshio;(6) there are the upwelling and downwelling at Section K4,which are located at the western and eastern parts of Section K4,respectively.更多还原