The turbulent diffusivity estimation in Prydz Bay, Antarctic

DING Wen-xiang; LIANG Chu-jin; LIAO Guang-hong; GAO Li-Bao

doi:10.3969/j.issn.1001-909X.2017.01.002

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Journal of Marine Sciences ›› 2017, Vol. 35 ›› Issue (1) : 14-24. DOI: 10.3969/j.issn.1001-909X.2017.01.002

The turbulent diffusivity estimation in Prydz Bay, Antarctic

DING Wen-xiang^1,2, LIANG Chu-jin^*1,2, LIAO Guang-hong^1,2, GAO Li-Bao³

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Abstract

Thorpe scale and turbulent diffusivities in Prydz Bay of Antarctica were calculated based on Thorpe method and Conductivity-Temperature-Depth data. The strength of turbulent overturn was analyzed and its spatial distribution was also investigated. The results show that the larger Thorpe scale and turbulent diffusivities occur in rough topographic area and near the sea floor, and the maximum value of turbulent diffusivities exceeds 10^-2 m²/s, which is about two or three orders of magnitude larger than that in the open ocean. Turbulent diffusivities and dissipation rate of turbulent kinetic energy show high-low-high vertical structure in some observational stations, especially in deep area. The larger values of buoyancy frequency appear in upper 500 m water column in deep area, but this phenomenon is not obvious in shallow area. The dissipation rates of turbulent kinetic energy in the stations around the point(67.25°S,73°E) and along the 78°E sections are quite large, which exceed 10^-6 w/kg, and even reach 10^-5 w/kg in a few stations.

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Prydz Bay / Thorpe scale / turbulent diffusivities / dissipation rate of turbulent kinetic energy

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DING Wen-xiang, LIANG Chu-jin, LIAO Guang-hong, GAO Li-Bao. The turbulent diffusivity estimation in Prydz Bay, Antarctic[J]. Journal of Marine Sciences. 2017, 35(1): 14-24 https://doi.org/10.3969/j.issn.1001-909X.2017.01.002

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