2004~2006年奄美大岛以东的琉球海流

基于2004~2006年12个航次的水文资料，用逆方法计算得到了奄美大岛以东AE断面琉球海流的流速和体积流量.再次证实琉球海流具有较稳定的次表层流核结构，流核位于110～600 m深度，并沿AE线分布于27.2°～28.2°N，流核的最大流速为15.1～80.0 cm·s^-1. 12个航次的平均流速断面显示了一个完整的次表层流核，其流核的最大流速为21.3 cm·s^-1, 流核的垂直和水平尺度分别为800 m 和 30 km. 观测结果表明，2004~2006年之间，琉球海流冬季、春季、夏季、秋季和年平均的流量分别为10.9,10.1,5.9,23.9和12.7×10⁶ m³·s^-1，秋季最强，夏季最弱.日本以南黑潮净流量为52.7×10⁶ m³·s^-1, 其中源于吐噶喇海峡黑潮和琉球海流的流量平均比为0.40.

The Ryukyu Current east of Amami-Ohshima during 2004 to 2006

An inverse calculation using twelve repeat hydrographic section data collected from 2004 to 2006 yields velocity structures and volume transports (VTs) of the Ryukyu Current (RC) in the region east of northern Ryukyu Islands. The results show that the RC is dominated by subsurface velocity core with maximum velocities varying from 15.1 to 80.0 cm·s^-1. The positions of subsurface maximum velocity core distribute between 110 and 600 m and 27.2°~28.2° N along the AE line. The mean velocity section exhibits a perfect subsurface velocity core with a mean maximum velocity of 21.3 cm·s^-1, and vertical and horizontal dimensions of 800 m and 30 km, respectively. The seasonal mean velocity sections exhibit that the RC is the strongest in autumn and the weakest in summer. The mean VT for winter, spring, summer, autumn, and all twelve observations are 10.9, 10.1, 5.9, 23.9, and 12.7×10⁶ m³·s^-1, respectively. The mean net VT of the Kuroshio south of Japan is estimated to be 52.7×10⁶ m³·s^-1. The rate of Kuroshio VT supplied by the Kuroshio from Tokara Strait and by the RC from the region southeast of Amami-Ohshima is 0.40.