Origin and formation of the Ryukyu Current revealed by HYCOM reanalysis

Wang Min; Liu Zhaojun; Zhu Xiaohua; Yan Xiaomei; Zhang Zhongzhe; Zhao Ruixiang

doi:10.1007/s13131-018-1329-7

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Article Navigation > Acta Oceanologica Sinica > 2019 > 38(11): 1-10

Wang Min, Liu Zhaojun, Zhu Xiaohua, Yan Xiaomei, Zhang Zhongzhe, Zhao Ruixiang. Origin and formation of the Ryukyu Current revealed by HYCOM reanalysis[J]. Acta Oceanologica Sinica, 2019, 38(11): 1-10. doi: 10.1007/s13131-018-1329-7

Citation:

Wang Min, Liu Zhaojun, Zhu Xiaohua, Yan Xiaomei, Zhang Zhongzhe, Zhao Ruixiang. Origin and formation of the Ryukyu Current revealed by HYCOM reanalysis[J]. Acta Oceanologica Sinica, 2019, 38(11): 1-10. doi: 10.1007/s13131-018-1329-7

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Origin and formation of the Ryukyu Current revealed by HYCOM reanalysis

doi: 10.1007/s13131-018-1329-7

1.
School of Oceanography, Shanghai Jiao Tong University, Shanghai 200030, China;State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
2.
State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
3.
State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China;School of Oceanography, Shanghai Jiao Tong University, Shanghai 200030, China
4.
Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
5.
College of Marine Science and Environment, Dalian Ocean University, Dalian 116023, China

Received Date: 2018-05-12

Abstract

Abstract

The origin of the Ryukyu Current (RC) and the formation of its subsurface velocity core were investigated using a 23-year (1993–2015) global Hybrid Coordinate Ocean Model (HYCOM) dataset. The volume transport of the RC comes from the Kuroshio eastward branch (KEB) east of Taiwan and part of the North Pacific Subtropical Gyre (p-NPSG). From the surface to 2 000 m depth, the KEB (p-NPSG) transport contributes 41.5% (58.5%) to the mean total RC transport. The KEB originally forms the subsurface velocity core of the RC east of Taiwan due to blockage of the subsurface Kuroshio by the Ilan Ridge (sill depth: 700 m). Above 700 m, the Kuroshio can enter the East China Sea (ECS) over the Ilan Ridge, meanwhile, the blocked Kuroshio below 700 m turns to the right and flows along the Ryukyu Islands. With the RC flowing northeastward, the p-NPSG contribution strengthens the subsurface maximum structure of the RC owing to the blockage of the Ryukyu Ridge. In the surface layer, the p-NPSG cannot form a stable northeastward current due to frequent disturbance by mesoscale eddies and water exchange through the gaps (with net volume transport into ECS) between the Ryukyu Islands.
- origins of Ryukyu Current|subsurface velocity core|volume transport|Kuroshio|HYCOM,

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References(24)

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