Pt. Shaw et Sy. Chao, SURFACE CIRCULATION IN THE SOUTH CHINA SEA, Deep-sea research. Part 1. Oceanographic research papers, 41(11-12), 1994, pp. 1663-1683
A three-dimensional, primitive-equation model with a free surface is u
sed to simulate the monthly circulation in the South China Sea. The mo
del has a resolution of 0.4 degrees in the horizontal and 21 layers in
the vertical in a region from 2 degrees N to 24 degrees N and from 99
degrees E to 124 degrees E. Inflow and outflow in the Kuroshio, throu
gh the Taiwan Strait, and between the Sunda Shelf and the Java Sea are
prescribed bimonthly. At the sea surface, the model is forced by mont
hly-averaged climatological winds and temperature and seasonally-avera
ged salinity. Several important features are reproduced in the model s
imulation. First, a strong coastal jet is present at the western bound
ary. The current is southward along the continental margin from China
to southern Vietnam in winter. In summer, the current is northward and
separates from the coast between 11 degrees N and 14 degrees N. The t
ransition in September begins as a southward undercurrent, which is re
motely forced by the northeast monsoon in the northern reaches of the
south China Sea. The undercurrent extends to the surface in about a mo
nth. Second, inflow through the Luzon Strait from October to February
transports the Kuroshio water in the top of 300 m of the water column
westward along the continental slope south of China. In summer, eastwa
rd flow in the Luzon Strait transports surface water west of Luzon to
the region east of Taiwan. Finally, a subsurface current, which is opp
osite to the surface current, exists over the Sunda Shelf and is drive
n by a pressure gradient set up by monsoon winds. These simulated curr
ents are in qualitative agreement with the circulation inferred from t
he available observations.