数值实验论证台湾暖流和对马暖流的关系

The remote connection of the Taiwan and Tsushima warm currents

台湾暖流和对马暖流均为沿中国东部海域大陆架的北向流。有学者认为存在"台湾-对马暖流流系"。现有的研究均未涉及台湾暖流和对马暖流在该系统中各自的动力作用。本文作者发现在该系统中对马暖流扮演更为重要的角色。借助一个三维斜压模式,作者设计了几组数值实验来讨论台湾暖流和对马暖流之间的动力学机制。结果显示台湾暖流对对马暖流几乎没有影响,而对马暖流却对台湾暖流存在重要影响。尽管对马暖流位于"下游区",通过"源-汇"驱动作用,其可以诱生约0.5×106m3/s的台湾暖流水。作者认为,能量通过地形波传导理论可能为这一动力学机制的合理解释。

The Taiwan Warm Current（TWC） and the Tsushima Warm Current（TSWC） flow northward over the shelf in the East China Sea（ECS）.Some previous studies consider them as a Taiwan-Tsushima Warm Current（TTWC） System.It seems that the TWC is dominant in the TTWC system because it is located at the ＂upstream＂ region of the whole system.In this paper,however,we find that the TSWC is more important in the TTWC system.Using a three-dimensional baroclinic model,we conduct several experiments to discuss the dynamic relationship between the TWC and TSWC.The results show that the TWC has little effect on the TSWC,while the TSWC has a significant effect on the TWC.We use source-sink driven mechanism along isobaths to explain this phenomenon.The perennial northward flow through the Tsushima Strait pumps the response over the northern shelf in the ECS that gives rise to the TWC.Although the TSWC is located at the ＂downstream＂ region,it could induce 0.5 Sv to TWC in annual mean.The possible mechanism can be explained here in terms of energy propagation by topographic waves.