Abstract
Variation in intermediate water salinity in the South China Sea (SCS) between the 1960s and 1980s was studied using historical hydrographic data. The results demonstrate that the water was significantly fresher in the 1980s than in the 1960s, indicating that vertical mixing at intermediate water depth was reduced in the 1980s. This was partially because of the change of the SCS meridional overturning circulation (MOC) connecting local intermediate water with deep water. Data assimilation showed a 0.5 Sv (1 Sv=106 m3 /s) reduction in the strength of the MOC, which is about one third of the mean SCS MOC. Because the SCS MOC is linked to the Pacific Ocean, such an interdecadal variation in the intermediate water SCS may reflect anthropogenic climate change in the world ocean.
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Supported by the National Basic Research Program of China (973 Program) (No. 2011CB403504), the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-Q11-02), and the National Natural Science Foundation of China (No. 40806003)
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Liu, C., Wang, D., Chen, J. et al. Freshening of the intermediate water of the South China Sea between the 1960s and the 1980s. Chin. J. Ocean. Limnol. 30, 1010–1015 (2012). https://doi.org/10.1007/s00343-012-1280-y
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DOI: https://doi.org/10.1007/s00343-012-1280-y