Spatial and temporal oscillation and long-term variation in sea surface temperature field of the South China Sea

Based on monthly mean sea surface temperature(SST),850hPa wind and subtropical high index over the western Pacific during 1950~2006,the spatial and temporal oscillation and long-term variation in SST field of the South China Sea(SCS) are analyzed by using empirical orthogonal function(EOF),polynomial function and spectrum analysis,and then the causes of SST interannual and long-term variation are discussed by using correlation and composite analysis.The results show that SST anomaly fields have two major patterns.SSTs over the South China Sea have spatially in-phase interannual variation and seasonal oscillation with out-of-phases between the west and east South China Sea.The SST in the central South China Sea exhibit significant interannual and interdecadal variations,and experienced a climate jump in 1981.The annual mean SST in the central South China Sea has increased by 0.92℃ from 1950 to 2006.It is also suggested that the interannual and long-term variations in SST of the South China Sea may be resulted from the meridional wind anomaly and zonal migration of the subtropical high over the western Pacific.