Submarine sills

The water exchange between the SCS and Pacific Ocean at the surface layer relates the monsoon to the exchange between the Kuroshio water and the SCS water. The winter monsoon forces the Kuroshio water to enter the Luzon Strait and even to reach the western coast of the NSCS. However, the summer monsoon drives the SCS water into the Pacific. The Philippines seawater enters the SCS perennially above the submarine sill in the Luzon Strait. In a word, the Kuroshio surface water does enter the SCS. 

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