Deep boundary current disintegration in Drake Passage
Deep boundary current disintegration in Drake Passage
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DOI：
10.1002/2013gl058617
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发表时间：
2014-01
影响因子：
5.2
通讯作者：
J. Brearley;K. Sheen;A. N. Naveira Garabato;D. Smeed;K. Speer;A. Thurnherr;M. Meredith;S. Waterman
中科院分区：
文献类型：
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作者：
J. Brearley;K. Sheen;A. N. Naveira Garabato;D. Smeed;K. Speer;A. Thurnherr;M. Meredith;S. Waterman
本文阐明了起源于东南太平洋并沿沿着南美洲大陆坡向南流动的深边界流的命运。海流将低盐度的通风不良的水（太平洋深水的一种，PDW）输送到德雷克海峡。在德雷克海峡以东，边界流破裂成新的反气旋涡旋，2009年12月至2012年3月的系泊数据中观察到了其中的9个例子。观测到的涡旋似乎主要源自西经60°附近的地形分离点，典型直径为20-60 km，伴随的Rossby数为0.1-0.3。这些功能很可能是负责运输PDW跨南极绕极流，解释附近的均匀化的德雷克通道下游的绕极深水属性。这种边界流破裂机制可能构成南大洋翻转环流的一个重要过程。
The fate of a deep boundary current that originates in the Southeast Pacific and flows southward along the continental slope of South America is elucidated. The current transports poorly ventilated water of low salinity (a type of Pacific Deep Water, PDW), into Drake Passage. East of Drake Passage, the boundary current breaks into fresh anticyclonic eddies, nine examples of which were observed in mooring data from December 2009 to March 2012. The observed eddies appear to originate mainly from a topographic separation point close to 60°W, have typical diameters of 20–60 km and accompanying Rossby numbers of 0.1–0.3. These features are likely to be responsible for transporting PDW meridionally across the Antarctic Circumpolar Current, explaining the near homogenization of Circumpolar Deep Water properties downstream of Drake Passage. This mechanism of boundary current breakdown may constitute an important process in the Southern Ocean overturning circulation.