Cite this paper:
LI Jianing, DONG Jihai, YANG Qingxuan, ZHANG Xu. Spatial-temporal variability of submesoscale currents in the South China Sea[J]. HaiyangYuHuZhao, 2019, 37(2): 474-485

Spatial-temporal variability of submesoscale currents in the South China Sea

LI Jianing1, DONG Jihai2, YANG Qingxuan1, ZHANG Xu3
1 Physical Oceanography Laboratory/CIMST, Ocean University of China, and Qingdao National Laboratory for Marine Science and Technology, Qingdao 266000, China;
2 Marine Science College, Nanjing University of Information Science & Technology, Nanjing 210044, China;
3 College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266000, China
Spatial and seasonal variabilities of submesoscale currents in the northeastern South China Sea are investigated by employing a numerical simulation with a horizontal resolution of 1 km. The results suggest that submesoscale currents are widespread in the surface mixed layer mainly due to the mixed layer instabilities and frontogenesis. In horizontal, submesoscale currents are generally more active in the north than those in the south, since that active eddies, especially cyclonic eddies, mainly occur in the northern area. Specifically, submesoscale currents are highly intensified in the east of Dongsha Island and south of Taiwan Island. In temporal sense, submesoscale currents are more active in winter than those in summer, since the mixed layer is thicker and more unstable in the winter. The parameterization developed by FoxKemper et al. is examined in terms of vertical velocity, and the results suggest that it could reproduce the vertical velocity if mixed layer instability dominates there. This study improves our understanding of the submesoscale dynamics in the South China Sea.
Key words:    submesoscale currents|spatial-seasonal variability|South China Sea (SCS)   
Received: 2018-04-09   Revised: 2018-05-24
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