Chinese Journal of Oceanology and Limnology

, Volume 28, Issue 5, pp 1102–1111 | Cite as

Mesoscale structure of the central South China Sea detected by SCSMEX Buoy and Argo float

  • Lili Zeng (曾丽丽)
  • Dongxiao Wang (王东晓)
  • Yan Du (杜岩)
  • Ping Shi (施平)
Article

Abstract

We addressed the mesoscale structure variation of the central South China Sea (SCS) with the measurements by a long-lived Argo float and a high-resolution ATLAS buoy during 1998–2002. T-S diagram indicates cooling and freshening events in 2000 and 2001 with lower salinity (0.5–0.8) and lower temperature (1–1.7°C). Significant decrease in the net heat flux and increase in the precipitation suggest that the cooling and freshening is due to extra forcing by the atmosphere. Additional to large year-to-year changes, intraseasonal variability is moderate in the research area. The axis of the maximum intraseasonal temperature and salinity signals are mainly located on the thermocline. Typically, amplitude and period of intraseasonal temperature is about 2°C and 40–60 days, and that of salinity is 0.3–0.5 and 35–60 days. Rapidly-changing winds, heat flux, and precipitation are critical in controlling the intraseasonal fluctuations of the mixed layer of the area. Studies on heat and freshwater balance in the mixed-layer further suggest that horizontal advection plays an important role in intraseasonal fluctuation in the upper ocean. In addition, the energetic mesoscale propagation radiated from the east boundary is linked to the intraseasonal variability in winter.

Keyword

South China Sea (SCS) upper ocean water mass Argo floats SCSMEX buoy 

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Copyright information

© Chinese Society for Oceanology and Limnology, Science Press and Springer Berlin Heidelberg 2010

Authors and Affiliations

  • Lili Zeng (曾丽丽)
    • 1
  • Dongxiao Wang (王东晓)
    • 1
  • Yan Du (杜岩)
    • 1
  • Ping Shi (施平)
    • 1
    • 2
  1. 1.Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouChina
  2. 2.Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantaiChina

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