An Eddy-Permitting Southern Ocean State Estimate
An Eddy-Permitting Southern Ocean State Estimate
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DOI：
10.1175/2009jpo4236.1
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发表时间：
2010-05-01
影响因子：
3.5
通讯作者：
Wunsch, Carl
中科院分区：
文献类型：
--
作者：
Mazloff, Matthew R.;Heimbach, Patrick;Wunsch, Carl
一个允许涡旋的南大洋大气环流模式是通过约束最小二乘法拟合到2005-06年的大型观测数据集。使用的数据包括Argo浮标剖面图、CTD天气剖面图、作为海洋学采样器的南方象海豹剖面图、XBT、测高观测[Envisat、Geosat、Jason-1和海洋地形实验（TOPEX）/Poseidon]，以及红外和微波辐射计观测的海面温度。伴随模型被用来确定下降方向，在最小化的失配函数，其每个元素已被加权的估计的观测加上模型误差。通过调整其控制向量（这里由初始和气象边界条件组成），该模型与数据几乎一致。虽然尚未实现完全一致，但现有的解决方案与2005年和2006年南大洋观测的绝大多数数据非常一致，并且比《2001年世界海洋地图集》（WOA 01）气候产品更好地代表了这些数据。估计捕获海洋的时间变化，在这方面是一个重大的改进，较早的静态逆估计。在估算期间，德雷克海峡的输运量为153 +/- 5 Sv（1 Sv相当于10（6）m（3）s（-1））。罗斯和威德尔极地环流输送量分别为20 +/- 5 Sv和40 +/- 8 Sv。在南纬32度范围内，有一个12 +/- 12 Sv的表面三角形翻转单元，一个17 +/- 12 Sv的中间单元和一个13 +/- 6 Sv的深海单元。南纬30度向北的热量和淡水异常输送为-0.3PW和0.7Sv，估计不确定度为0.5PW和0.2Sv。风力发电的净功率为2.1 +/- 1.1 TW。涉及短时间和空间尺度动力学的南大洋理论现在可以用已知与现代观测数据集兼容的动态和热力学现实的大气环流模型解决方案来测试。
An eddy-permitting general circulation model of the Southern Ocean is fit by constrained least squares to a large observational dataset during 2005-06. Data used include Argo float profiles, CTD synoptic sections, Southern Elephant Seals as Oceanographic Samplers (SEaOS) instrument-mounted seal profiles, XBTs, altimetric observations [Envisat, Geosat, Jason-1, and Ocean Topography Experiment (TOPEX)/Poseidon], and infrared and microwave radiometer observed sea surface temperature. An adjoint model is used to determine descent directions in minimizing a misfit function, each of whose elements has been weighted by an estimate of the observational plus model error. The model is brought into near agreement with the data by adjusting its control vector, here consisting of initial and meteorological boundary conditions. Although total consistency has not yet been achieved, the existing solution is in good agreement with the great majority of the 2005 and 2006 Southern Ocean observations and better represents these data than does the World Ocean Atlas 2001 (WOA01) climatological product. The estimate captures the oceanic temporal variability and in this respect represents a major improvement upon earlier static inverse estimates. During the estimation period, the Drake Passage volume transport is 153 +/- 5 Sv (1Sv equivalent to 10(6) m(3) s(-1)). The Ross and Weddell polar gyre transports are 20 +/- 5 Sv and 40 +/- 8 Sv, respectively. Across 32 degrees S there is a surface meridional overturning cell of 12 +/- 12 Sv, an intermediate cell of 17 +/- 12 Sv, and an abyssal cell of 13 +/- 6 Sv. The northward heat and freshwater anomaly transports across 30 degrees S are -0.3 PW and 0.7 Sv, with estimated uncertainties of 0.5 PW and 0.2 Sv. The net rate of wind work is 2.1 +/- 1.1 TW. Southern Ocean theories involving short temporal-and spatial-scale dynamics may now be tested with a dynamically and thermodynamically realistic general circulation model solution that is known to be compatible with the modern observational datasets.