Long term trend of sea surface temperature in the South China Sea

Abstract

Using HAdISST the long term trend in the South China Sea (SCS) sea surface temperature (SST) between 1950 and 2008 is investigated. In general SST has been increased since 1950, but the rate of increase is spatiotemporally uneven. Winter warming rate is greater than that of summer. In both seasons the rate of increase is greater during 1980s. Winter warming rate is greater over the deeper basin while summer warming rate is greater over the shallower southeastern part. In summer the weakening of southwesterly monsoon reduces upwelling along the east coast of Vietnam to warm the surface. On the other hand, the net surface heat flux, however, is reduced and cannot contribute to the warming. In winter the net heat flux into the sea increases and could contribute to the warming. The spatial pattern of the heat flux, however, is different from that of the warming. The heat flux is increased over the coastal area where warming is small, but decreased in deeper part where warming is greater. After 1980′s the northeasterly monsoon winds weakens to reduce the southward western boundary currents, and subsequently cold advection and to warm the area.r warming rate is greater than that of summer. In both seasons the rate of increase is greater during 1980s. Winter warming rate is greater over the deeper basin while summer warming rate is greater over the shallower southeastern part. In summer the weakening of southwesterly monsoon reduces upwelling along the east coast of Vietnam to warm the surface. On the other hand, the net surface heat flux, however, is reduced and cannot contribute to the warming. In winter the net heat flux into the sea increases and could contribute to the warming. The spatial pattern of the heat flux, however, is different from that of the warming. The heat flux is increased over the coastal area where warming is small, but decreased in deeper part where warming is greater. After 1980′s the northeasterly monsoon