Cite this paper:
REN Qiang, YU Fei, NAN Feng, WANG Jianfeng, XUAnqi. Intraseasonal variability of the Kuroshio east of Taiwan, China, observed by subsurface mooring during 2016-2017[J]. Journal of Oceanology and Limnology, 2020, 38(5): 1408-1420

Intraseasonal variability of the Kuroshio east of Taiwan, China, observed by subsurface mooring during 2016-2017

REN Qiang1,2,3, YU Fei1,2,3,4, NAN Feng1,2,3,4, WANG Jianfeng1,2,3,4, XUAnqi1,2,3
1 CAS Key Laboratory of Ocean Circulation and Wave Studies, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;
2 University of Chinese Academy of Sciences, Beijing 100049, China;
3 Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China;
4 Pilot National Laboratory for Marine Science and Technology(Qingdao), Qingdao 266071, China
Abstract:
The mean velocity structure and variability of the Kuroshio east of Taiwan, China, were investigated using mooring observations acquired at 23°N/122°E between January 2016 and May 2017. Power spectrum analysis reveals marked intraseasonal variability in 70-95 days in the meridional Kuroshio velocity in the upper 800 m. Hybrid Coordinate Ocean Model assimilation data adequately reproduce variations of the Kuroshio. Westward propagating mesoscale eddies that originated from the Subtropical Countercurrent play an important role in intraseasonal variability in the Kuroshio velocity. Cyclonic (anticyclonic) eddies are often associated with negative (positive) sea surface height anomaly, resulting in positive (negative) potential vorticity in the subsurface layer of the eddy center, which decreases (increases) isopycnal slope and then weakens (strengthens) the Kuroshio. When anticyclonic (cyclonic) eddies are active, the Kuroshio axis moves offshore (inshore). Corresponding to the Kuroshio intraseasonal variability (ISV), the variation of the intermediate water salinity also had a significant ISV induced by the mesoscale eddies.
Key words:    intraseasonal variability|Kuroshio|mesoscale eddy|intermediate water   
Received: 2019-11-18   Revised: 2019-12-30
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