Eddy forcing of the mean flow in the Southern Ocean
Eddy forcing of the mean flow in the Southern Ocean
复制标题
南大洋平均流量的涡流强迫
DOI：
10.1029/2000jc900332
复制
发表时间：
2001
影响因子：
--
通讯作者：
E. Ash
中科院分区：
文献类型：
--
作者：
C. Hughes;E. Ash
我们研究的力量（或加速度）施加的涡旋对南大洋的平均流量使用映射的海面高度异常来自卫星高度计测量。我们比较这与射流的平均流量的平均海表温度的梯度增加的区域所示的位置。涡动力本身并不是最重要的;相反，涡动力的旋度影响平均流，因此由涡动能梯度引起的无旋力可以忽略不计，剩下的剩余部分可以用涡度通量来解释。与以前的建模和测高研究不同，我们发现，涡的作用，以减速一些最强的射流和作为涡源的其他。最强的喷流显然不是由涡流加速的。然而，由于不清楚海平面温度与平均流量之间的关系，因此仍然存在一个解释问题。这种模糊性只能通过测量平均流来完全解决，这需要一个在100公里量级的长度尺度上精确的大地水准面。
We examine the force (or acceleration) exerted by eddies on the mean flow of the Southern Ocean using mapped sea surface height anomalies derived from satellite altimeter measurements. We compare this with the position of jets in the mean flow indicated by regions of increased gradient in the mean sea surface temperature. The eddy force itself is not of primary importance; rather, the curl of that force affects the mean flow, so the irrotational force due to the gradient of eddy kinetic energy can be ignored, leaving a remainder that can be interpreted in terms of the eddy vorticity flux. Unlike previous modeling and altimetric studies, we find that the eddies act to decelerate some of the strongest jets and act as vorticity sources for others. The strongest jets are clearly not accelerated by eddies. A problem of interpretation does remain, however, since it is not clear how sea surface temperatures are related to the mean flow. This ambiguity can only be completely resolved by measurement of the mean flow, requiring a geoid that is accurate at length scales of order 100 km.