The variation of subsurface salinity in northern South China Sea and its relationship to the bifurcation of the North Equatorial Current

Abstract

Abstract: Luzon Strait is an important water exchange channel between South China Sea and Philippine Sea. As a famous western boundary current in the North Pacific, the Kuroshio has an important impact on the South China Sea circulation. In this research, we extracted the salinity-maximum at density of 23.0~25.5 kg/m³ and studied further the relation between the Kuroshio intrusion and bifurcation of the North Equatorial Current with CTD data of 1991—2011 and the satellite altimeter data. The results show that: (1) The ways of Kuroshio intrusion in SCS are diverse, including branch, bending and loop. (2) In different years, Kuroshio intrusion is quite different and the range of salinity-maximum can be more than 0.3 in the 120°E section. (3) The bifurcation of North Equatorial Current has a great effect on the intrusion of Kuroshio in South China Sea: When the bifurcation of North Equatorial Current moves to north, the Kuroshio intrusion in South China Sea is strong; when it moves to south, the Kuroshio intrusion is weak.

Key words: South China Sea, Kuroshio, salinity-maximum, the bifurcation of North Equatorial Current

CLC Number:

P731

YANG Long-qi, XU Dong-feng, XU Ming-quan, WANG Jun, SHI Peng-fei. The variation of subsurface salinity in northern South China Sea and its relationship to the bifurcation of the North Equatorial Current[J]. Journal of Marine Sciences, 2013, 31(3): 15-24.

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