基于长时序卫星测高数据的印度洋中尺度涡遥感调查和验证

Investigation and validation of mesoscale eddy in the Indian Ocean based on long time series satellite altimetry data

摘要:

海洋湍流的基本结构之一是各种尺度的涡旋，既有构成背景场流的随机小尺度涡旋又有在统计意义上存在拟序结构的中尺度涡。针对印度洋广泛存在的中尺度涡，本研究使用长时间序列、空间分布均匀的卫星测高数据，开展了印度洋中尺度涡遥感调查和结果验证。结果显示，印度洋中尺度涡主要分布在南印度洋南极绕极流区域、澳大利亚西部海域、莫桑比克海峡以及北印度洋的阿拉伯海以及孟加拉湾。北印度洋由于空间区域所限，其中尺度涡生命周期和移动距离均较小；而南印度洋存在大量长生命周期的中尺度涡，部分涡旋可以横跨整个南印度洋运动。基于Argo现场观测数据以及多源海洋三维再处理数据，对中尺度涡遥感调查结果进行了验证，中尺度涡表层遥感信号与水下温度信号显示了较好的一致性。

Abstract:

One of the fundamental structures of ocean turbulence is the presence of various scales of eddies, with a background flow consisting of numerous random small eddies and coherent structure of mesoscale eddies existing in a statistical sense. Focusing on the mesoscale eddies prevalent in the Indian Ocean, this study carried out a remote sensing investigation and result validation of mesoscale eddies using long time-series and spatially uniform satellite altimetry data. The results indicate that mesoscale eddies in the Indian Ocean are primarily distributed in the region of in the Antarctic Circumpolar Current region, the western waters of Australia, the Mozambique Channel in the Southern Indian Ocean, and the Arabian Sea and the Bay of Bengal in the northern Indian Ocean. In the northern Indian Ocean, due to the limitation of the spatial region, mesoscale eddies exhibit smaller lifetimes and shorter propagation distances. In contrast, in the southern Indian Ocean, there are a large number of mesoscale eddies with long lifetimes, and some of them can move across the entire southern Indian Ocean. Based on the Argo in situ observation data and multi-observation ocean 3D reprocessing data, the remote sensing investigation results of mesoscale eddies are validated, and the remote sensing surface signals of mesoscale eddies shows good agreement with the underwater temperature signal.