Observed eddy dissipation in the Agulhas Current
Observed eddy dissipation in the Agulhas Current
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DOI：
10.1002/2016gl069480
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发表时间：
2016-02
影响因子：
5.2
通讯作者：
Laura Braby;B. Backeberg;I. Ansorge;M. Roberts;M. Krug;C. Reason
中科院分区：
文献类型：
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作者：
Laura Braby;B. Backeberg;I. Ansorge;M. Roberts;M. Krug;C. Reason
从一个全球性的数据集的自动跟踪涡的厄古拉斯电流结合表面漂流物以及地转流从卫星高度计的涡特性分析，它表明，从莫桑比克海峡和马达加斯加南部的涡消散，因为他们的方法的厄古拉斯电流。通过跟踪海流核心的离岸位置及其在30°S处与涡旋相关的速度，证明涡旋耗散是通过动量转移发生的，其中反气旋始终引起正速度异常，气旋降低速度并引起离岸蜿蜒。反气旋（气旋）涡流相互作用事件的复合分析表明，正（负）速度异常以44 km/d（23 km/d）的速度在阿古拉斯海流中向下游传播。许多模型都不能代表这些涡耗散过程，影响了我们对阿古拉斯海流的理解。
Analyzing eddy characteristics from a global data set of automatically tracked eddies for the Agulhas Current in combination with surface drifters as well as geostrophic currents from satellite altimeters, it is shown that eddies from the Mozambique Channel and south of Madagascar dissipate as they approach the Agulhas Current. By tracking the offshore position of the current core and its velocity at 30°S in relation to eddies, it is demonstrated that eddy dissipation occurs through a transfer of momentum, where anticyclones consistently induce positive velocity anomalies, and cyclones reduce the velocities and cause offshore meanders. Composite analyses of the anticyclonic (cyclonic) eddy‐current interaction events demonstrate that the positive (negative) velocity anomalies propagate downstream in the Agulhas Current at 44 km/d (23 km/d). Many models are unable to represent these eddy dissipation processes, affecting our understanding of the Agulhas Current.