Sea surface dynamic topography and geostrophic current over the South China Sea from Geosat altimeter observation

Based on the Geosat altimetric data in 1987 and 1988, the distributions of seasonal anomaly of dynamical topography over the South China Sea are analysed. A two-dimensional collinear adjustment method is developed to reduce the calculation errors for the orbit height. The results give a general agreement to those from the in situ observations,especially over the northern area where the seasonal variations of the geostrophic circulation over the South China Sea are anticyclonic in summer, and are cyclonic in winter. It is shown that the altimeter data are efficient in deriving the seasonal variation features of geostrophic current over the South China Sea.