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

南海南部上层的湍流混合特征

doi: 10.1007/s13131-015-0743-3

1.
中国科学院南海海洋研究所热带海洋环境国家重点实验室, 广州, 510301
2.
中国科学院南海海洋研究所热带海洋环境国家重点实验室, 广州, 510301;中国科学院大学, 北京, 10049

基金项目: 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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出版历程
- 收稿日期: 2015-03-19
- 修回日期: 2015-06-02

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

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

摘要

摘要: 基于2012年8月在中国南海10oN海域进行的微尺度湍流观察资料,分析了650米以浅的湍流混合特征.结果表明在该纬度南海的涡扩散系数要比相同纬度的开阔大洋大一个量级,而强流速剪切及粗糙地形是造成南海南部海域混合增强的主要机制.上混合层最大涡扩散系数可达10^-2m²/s量级;温跃层阻隔了上混合层强混合向下传递,涡扩散系数最弱;温跃层以下,背景涡扩散系数约为10^-6m²/s量级,其随着深度的增大而增加,最大可达10^-3m²/s量级.
- 南海南部 /
- 湍流混合 /
- 湍动能耗散率 /
- 地形
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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参考文献(37)

Alford M H, Klymak J M, Carter G S. 2014. Breaking internal lee waves at Kaena Ridge, Hawaii. Geophysical Research Letters, 41(3): 906-912

Callaghan A H, Ward B, Vialard J. 2014. Influence of surface forcing on near-surface and mixing layer turbulence in the tropical Indian Ocean. Deep-Sea Research Part I: Oceanographic Research Papers, 94: 107-123

Duda T F, Lynch J F, Irish J D, et al. 2004. Internal tide and nonlinear internal wave behavior at the continental slope in the northern South China Sea. IEEE Journal of Oceanic Engineering, 29: 11051130

Ferrari R, Wunsch C. 2009. Ocean circulation kinetic energy: reservoirs, sources, and sinks. Annual Review of Fluid Mechanics, 41: 253-282

Garrett C. 2003. Internal tides and ocean mixing. Science, 301(5641): 1858-1859

Gayen B, Sarkar S. 2013. Degradation of an internal wave beam by parametric subharmonic instability in an upper ocean pycnocline. Journal of Geophysical Research: Oceans, 118(9): 4689-4698

Gregg M C, Sanford T B, Winkel D P. 2003. Reduced mixing from the breaking of internal waves in equatorial waters. Nature, 422(6931): 513-515

Hibiya T, Nagasawa M. 2004. Latitudinal dependence of diapycnal diffusivity in the thermocline estimated using a finescale parameterization. Geophysical Research Letters, 31: L01301

Jan S, Chern C S, Wang J, et al. 2007. Generation of diurnal K1 internal tide in the Luzon Strait and its influence on surface tide in the South China Sea. Journal of Geophysical Research, 112: C06019

Klymak J M, Gregg M C. 2004. Tidally generated turbulence over the Knight Inlet sill. Journal of Physical Oceanography, 34(5): 1135-1151

Kunze E, Firing E, Hummon M J, et al. 2006. Global abyssal mixing inferred from lowered ADCP shear and CTD strain profiles. Journal of Physical Oceanography, 36(8): 1553-1576

Laurent L S, Schmitt R W. 1999. The contribution of salt fingers to vertical mixing in the north Atlantic tracer release experiment. Journal of Physical Oceanography, 29(7): 1404-1424

Liu Zhiyu, Lozovatsky I. 2012. Upper pycnocline turbulence in the northern South China Sea. Chinese Science Bulletin, 57(18): 2302-2306

Lu Yuanzheng, Zhou Shengqi, Cen Xianrong, et al. 2014. Salt finger and turbulence mixing in the upper layer of the central South China Sea. Oceanologia et Limnologia Sinica (in Chinese), 45(6): 1159-1167

Melet A, Hallberg R, Legg S, et al. 2013. Sensitivity of the ocean state to the vertical distribution of internal-tide-driven mixing. Journal of Physical Oceanography, 43(3): 602-615

Melet A, Hallberg R, Legg S, et al. 2014. Sensitivity of the ocean state to lee waves-driven mixing. Journal of Physical Oceanography, 44(3): 900-921

Moum J N, Caldwell D R, Paulson C A. 1989. Mixing in the equatorial surface layer and thermocline. Journal of Geophysical Research: Oceans, 94(C2): 2005-2022

Müller P, Holloway G, Henyey F, et al. 1986. Nonlinear interactions among internal gravity waves. Reviews of Geophysics, 24(3): 493-536

Nasmyth P. 1970. Oceanic turbulence [dissertation]. Vancouver: University of British Columbia, 69

Naveira Garabato A C, Polzin K L, King B A, et al. 2004. Widespread intense turbulent mixing in the Southern Ocean. Science, 303(5655): 210-213

Nikurashin M, Ferrari R. 2010. Radiation and dissipation of internal waves generated by geostrophic motions impinging on smallscale topography: Theory. Journal of Physical Oceanography, 40(5): 1055-1074

Nikurashin M, Vallis G, Adcroft A. 2013. Routes to energy dissipation for geostrophic flows in the Southern Ocean. Nature Geoscience, 6(1): 48-51

Osborn T R. 1980. Estimates of the local rate of vertical diffusion from dissipation measurements. Journal of Physical Oceanography, 10(1): 83-89

Peters H, Gregg M C, Toole J M. 1988. On the parameterization of equatorial turbulence. Journal of Geophysical Research- Oceans, 93(C2): 1199-1218

Ruddick B. 1983. A practical indicator of the stability of the water column to double-diffusive activity. Deep-Sea Research Part A: Oceanographic Research Papers, 30(10): 1105-1107

Schmitt R W, Ledwell J R, Montgomery E T, et al. 2005. Enhanced diapycnal mixing by salt fingers in the thermocline of the tropical Atlantic. Science, 308(5722): 685-688

Shang Xiaodong, Liu Qian, Xie Xiaohui, et al. 2015. Source and seasonal variability of internal tides in the southern South China Sea. Deep-Sea Research Part I: Oceanographic Reseach Papers, 98:43-52

Shay T J, Gregg M C. 1986. Convectively driven turbulent mixing in the upper ocean. Journal of Physical Oceanography, 16(11): 1777-1798

St Laurent L. 2008. Turbulent dissipation on the margins of the South China Sea. Geophysical Research Letters, 35: L23615

St Laurent L, Garrett C. 2002. The role of internal tides in mixing the deep ocean. Journal of Physical Oceanography, 32(10): 2882-2899

Tian Jiwei, Yang Qingxuan, Zhao Wei. 2009. Enhanced diapycnal mixing in the South China Sea. Journal of Physical Oceanography, 39(12): 3191-3203

Tian Jiwei, Zhou Lei, Zhang Xiaoqian. 2006. Latitudinal distribution of mixing rate caused by the M₂ internal tide. Journal of Physical Oceanography, 36(1): 35-42

Whalen C B, Talley L D, MacKinnon J A. 2012. Spatial and temporal variability of global ocean mixing inferred from Argo profiles. Geophysical Research Letters, 39: L18612

Wolk F, Yamazaki H, Seuront L, et al. 2002. A new free-fall profiler for measuring biophysical microstructure. Journal of Atmospheric and Oceanic Technology, 19(5): 780-793

Yang Qingxuan, Tian Jiwei, Zhao Wei, et al. 2014. Observations of turbulence on the shelf and slope of northern South China Sea. Deep-Sea Research Part I: Oceanographic Research Papers, 87: 43-52

You Yuzhu. 2002. A global ocean climatological atlas of the Turner angle: implications for double-diffusion and water-mass structure. Deep-Sea Research Part I: Oceanographic Research Papers, 49(11): 2075-2093

Zhao Zhongxiang, Alford M H. 2006. Source and propagation of internal solitary waves in the northeastern South China Sea. Journal of Geophysical Research-Oceans, 111: C11012

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文章访问数: 1590
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南海南部上层的湍流混合特征

doi: 10.1007/s13131-015-0743-3

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出版历程

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

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出版历程

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