黑潮与东海水交换研究

The East China Seas exchange with the Kuroshio

利用高分辨率ROMS(regional ocean modeling system)数值模式模拟东海地区的多年平均流态。数值模拟结果在黑潮的流速、路径、流量等方面与近年来对黑潮的认识相一致。利用模式结果,计算东海及邻近海域主要水道的水通量。结果表明:台湾海峡、中国台湾-西表岛之间水道是海水进入东海的主要通道,对马海峡、吐噶喇海峡、大隅海峡与西表岛-宫古岛-冲绳岛-庵美大岛之间水道是海水流出东海的主要通道。分析PN断面的流量的变化特征,结果表明黑潮流量在春季与夏季较大,秋季与冬季较小,年平均流量为24.16 Sv,与前人研究结果一致。计算跨越200 m等深线的年平均净向岸体积输送为0.99 Sv,在台湾东北与九州西南地区表现为黑潮入侵陆架地区,年平均入侵流量分别为1.907 Sv与0.065 Sv,在黑潮中段地区,跨越200 m等深线流量呈现交错状分布,年平均净通量为0.982 Sv,表现为由东海陆架地区流向黑潮。上述结果对黑潮与东海之间物质与能量交换研究有一定参考价值。

In this study,we used the high-resolution numerical model ROMS(regional ocean modeling system)to simulate the current system in the East China Sea.The numerical simulation results are consistent with our current understanding of the Kuroshio.The Taiwan Strait and the channel between Taiwan and Iriomote Island are the main channels of water flowing into the East China Sea.The Tsushima Strait,the Tokara Strait,the Osumi Strait,and the channels between the Ryukyu Islands are the main channels of water flowing out.Our results indicate that the Kuroshio flow is greater during spring and summer,with an annual flux of 24.16 Sv.We determined the Kuroshio net onshore flux across the 200 m isobath to be 0.99 Sv.The Kuroshio onshore flux has two major sources-the Kurosho intrusion northeast of Taiwan and the Kuroshio separation southwest of Kyushu-with the former providing an annually averaged onshore flux of 1.907 Sv and the latter an annually averaged onshore flux of 0.065 Sv.We estimate the annually averaged onshore flux of the Kuroshio at Midway to be 0.982 Sv.