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Observations of upper layer turbulent mixing in the southern South China Sea

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Abstract

A turbulent microstructure experiment was undertaken at a low latitude of 10°N in the South China Sea in late August 2012. The characteristics of the eddy diffusivity above 650 m were analyzed, which is one order of magnitude larger than that in the open ocean at that low latitude. Enhanced eddy diffusivities by strong shears and sharp changes in topography were observed. The strongest eddy diffusivity occurred in the mixed layer, and it reached O(10–2 m2/s). Strong stratification in the thermocline inhibited the penetration of surface eddy diffusivities through the thermocline, where the mixing was weakest. Below the thermocline, where the background eddy diffusivity was approximately O(10–6 m2/s), the eddy diffusivity increased with depth, and its largest value was O(10–3 m2/s).

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Authors and Affiliations

  1. State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China

    Xiaodong Shang, Yongfeng Qi, Guiying Chen & Changrong Liang

  2. University of Chinese Academy of Sciences, Beijing, 100049, China

    Yongfeng Qi & Changrong Liang

Authors
  1. Xiaodong Shang
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  2. Yongfeng Qi
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  3. Guiying Chen
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  4. Changrong Liang
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Correspondence to Xiaodong Shang.

Additional information

Foundation item: The “CAS/SAFEA International Partnership Program for Creative Research Teams” of Chinese Academy of Seiences under contract Nos XDA11010202, 2013CB430303 and 41376022, 41276021 and 41276023.

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Shang, X., Qi, Y., Chen, G. et al. Observations of upper layer turbulent mixing in the southern South China Sea. Acta Oceanol. Sin. 34, 6–13 (2015). https://doi.org/10.1007/s13131-015-0743-3

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  • DOI: https://doi.org/10.1007/s13131-015-0743-3

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