Kuroshio intrusion into the South China Sea with an anticyclonic eddy: evidence from underwater glider observation

  • Zenghong LiuEmail author
  • Xingrong Chen
  • Jiancheng Yu
  • Dongfeng Xu
  • Chaohui Sun


In this study, high-resolution temperature and salinity data obtained from three Sea-Wing underwater gliders were used together with satellite altimeter data to track the vertical thermohaline structure of an anticyclonic eddy that originated from the loop current of the Kuroshio southwest of Taiwan Island. One of the gliders crossed the entire eddy and it observed a remarkable warm anomaly of as much as 3.9°C extending to 500 dbar from the base of the mixed layer. Conversely, a positive salinity anomaly was found to be above 200 dbar only in the anticyclonic eddy, with a maximum value of >0.5 in the mixed layer. Below the mixed layer, water of higher salinity (>34.7) was found, which could have been preserved through constrained vertical mixing within the anticyclonic eddy. The salinity in the upper layer of the anticyclonic eddy was much similar to that of the northwestern Pacific Ocean than the northern South China Sea, reflecting Kuroshio intrusion with anticyclonic eddy shedding from the loop current.


anticyclonic eddy South China Sea Kuroshio Sea-Wing underwater glider 


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Copyright information

© Chinese Society for Oceanology and Limnology, Science Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Zenghong Liu
    • 1
    Email author
  • Xingrong Chen
    • 2
  • Jiancheng Yu
    • 3
  • Dongfeng Xu
    • 1
  • Chaohui Sun
    • 1
  1. 1.State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of OceanographyMinistry of Natural ResourcesHangzhouChina
  2. 2.National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijingChina
  3. 3.State Key Laboratory of Robotics, Shenyang Institute of AutomationChinese Academy of SciencesShenyangChina

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