南印度洋Rossby波影响阿古拉斯流涡动能低频变率的机制

阿古拉斯流是印度洋主要的西边界流之一。作为南半球副热带环流的一部分，阿古拉斯流系促成了印度洋-南大洋-大西洋洋盆之间的物质和能量的交换。同时，阿古拉斯流位于南印度洋西向Rossby波传输的下游，其海面高度、温跃层、上层海水层结调整均受到太平洋-印度洋大尺度洋盆间波导的影响，跨海盆的物质和能量在此积累和交换。因此，阿古拉斯流区的物质和能量输运不仅受到内区斜压、正压过程调整，也受到大尺度洋流、海盆尺度波动过程的补充和调控。本项目着眼于研究南印度洋Rossby波对阿古拉斯流涡动能年际、年代际变率的影响和机制，拟完成：1）研究阿古拉斯流及周边环流结构；2）研究南印度洋Rossby波在阿古拉斯上游流区的传播以及造成的温跃层调整过程；3）研究阿古拉斯流的涡动能强度和分布的低频变化及对波动的响应。本项目的实施有助于推进对区域海洋动力学的认识和掌握，加深对海洋西边界波-流作用过程及动力机制的理解。

The Agulhas Current is one of the main western boundary currents of the Indian Ocean. As a part of the Southern subtropical circulation, the Agulhas current system facilitates the exchange of mass, momentum, heat, and salinity among the Indian Ocean, Southern Ocean, and Atlantic ocean. Meantime, the Agulhas current is located at the western end of the westward Rossby wave in the southern Indian Ocean, and the sea surface eight, thermocline and stratification of the upper ocean are all affected by the large-scale inter-basin waveguide, which makes the energy from the Pacific converge in this region. Water mass and energy transport in the Agulhas current region is thus not only regulated by baroclinic and barotropic processes in the inner region, but also supplemented by large-scale ocean current and basin scale fluctuation processes. This project focuses on the influence and mechanism of the Indo-Pacific waveguide on the inter-annual and decadal variability of the eddy kinetic energy of the Agulhas current. The main research contents of this project include: 1) to research the Agulhas current and adjacent circulation; 2) to study the propagation process of Rossby wave of Southern Indian Ocean in Agulhas flow region and the thermocline adjustment; 3) to study the low frequency variation of the intensity and distribution of eddy kinetic energy and energy budget of Agulhas current. This project is conducive to understanding the regional ocean dynamics and coupling process of the ocean system.