The variation of turbulent diapycnal mixing at 18&#176;N in the South China Sea stirred by wind stress

LIU Yongzheng; JING Zhao; WU Lixin

doi:10.1007/s13131-017-1067-2

风应力搅拌下南海18°N断面跃密混合的变化

doi: 10.1007/s13131-017-1067-2

中国海洋大学, 物理海洋重点实验室, 青岛国家海洋科学与技术实验室, 青岛, 266100;美国德州农工大学, 海洋学系, 卡城, 77843-3146

基金项目: The National Basic Research Program (973 Program) of China under contract No. 2013CB956201; the National Natural Science Foundation of China under contract Nos 41521091, U1406401 and 41622602; the Global Change Project under contract No. GASI-03-01-01-05.

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- 收稿日期: 2016-03-19

The variation of turbulent diapycnal mixing at 18°N in the South China Sea stirred by wind stress

Physical Oceanography Laboratory, Ocean University of China/CIMST, Qingdao 266100, China;Qingdao National Laboratory for Marine Science and Technology, Qingdao 266100, China

摘要

摘要: 利用2004至2010年每年9月的CTD数据，基于细尺度参数化方案估计南海18°N断面跃密混合的时空变化。时空平均的涡旋扩散系数比外大洋的大一个量级，可以达到10^-4 m²/s。在南海内潮和近惯性内波都对跃密混合的供能起重要作用。前者主导了深海的跃密混合，然而对上层海洋的贡献也是不可忽略的，会增强在粗糙海底区域上层的跃密混合。比较起来，风生惯性内波的影响主要限制在海洋上层。无论在平坦或粗糙海底区域，随着风输入近惯性能量的增加，从2005至2010年上700 m跃密混合有增加趋势。
- 跃密混合 /
- 扩散率 /
- 风生近惯性内波 /
- 海底地形
Abstract: The spatial and temporal variations of turbulent diapycnal mixing along 18°N in the South China Sea (SCS) are estimated by a fine-scale parameterization method based on strain, which is obtained from CTD measurements in yearly September from 2004 to 2010. The section mean diffusivity can reach~10^-4 m²/s, which is an order of magnitude larger than the value in the open ocean. Both internal tides and wind-generated near-inertial internal waves play an important role in furnishing the diapycnal mixing here. The former dominates the diapycnal mixing in the deep ocean and makes nonnegligible contribution in the upper ocean, leading to enhanced diapycnal mixing throughout the water column over rough topography. In contrast, the influence of the wind-induced near-inertial internal wave is mainly confined to the upper ocean. Over both flat and rough bathymetries, the diapycnal diffusivity has a growth trend from 2005 to 2010 in the upper 700 m, which results from the increase of wind work on the near-inertial motions.
- diapycnal mixing /
- diffusivity /
- wind-induced near-inertial internal wave /
- topography

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参考文献(26)

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文章访问数: 923
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风应力搅拌下南海18°N断面跃密混合的变化

doi: 10.1007/s13131-017-1067-2

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The variation of turbulent diapycnal mixing at 18°N in the South China Sea stirred by wind stress

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