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

SHANG Xiaodong; QI Yongfeng; CHEN Guiying; LIANG Changrong

doi:10.1007/s13131-015-0743-3

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SHANG Xiaodong, QI Yongfeng, CHEN Guiying, LIANG Changrong. Observations of upper layer turbulent mixing in the southern South China Sea[J]. Acta Oceanologica Sinica, 2015, 34(11): 6-13. doi: 10.1007/s13131-015-0743-3

Citation:

SHANG Xiaodong, QI Yongfeng, CHEN Guiying, LIANG Changrong. Observations of upper layer turbulent mixing in the southern South China Sea[J]. Acta Oceanologica Sinica, 2015, 34(11): 6-13. doi: 10.1007/s13131-015-0743-3

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

doi: 10.1007/s13131-015-0743-3

1.
State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
2.
State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China;University of Chinese Academy of Sciences, Beijing 100049, China

Received Date: 2015-03-19
Rev Recd Date: 2015-06-02

Abstract

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).
- southern South China Sea,
- turbulent mixing,
- dissipation rate,
- topography

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References(37)

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