COMPARISION OF THE SCS SUMMER MONSOON ONSET-CHARACTERISTICS DERIVED FROM DIFFERENT DATASETS

doi:10.3969/j.issn.1004-4965.2001.01.004

Abstract：In this study, the basic characteristics of South China Sea (CSC)summer monsoon onset are analyzed and compared using different datasets. Those include the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP), National Meteorological Center global wind analysis, outgoing longwave radiation (OLR), and upper-tropospheric water vapor band brightness temperature (BT) observed with NOAA polar orbiting satellites. Results show that the BT can reflect some characteristics of SCS monsoon onset but it can not well depict the some information of local precipitation more details. OLR can reflect well the precipitation that lied over oceans but the low OLR over lands may be influenced by low surface temperature. 850 hPa wind alone can not determine the onset of summer monsoon. For describing the onset of SCS summer monsoon, the domain of SCS is reasonable to be determined in central-north part of SCS because the annual precipitation and convection continue to appear in the south part of SCS for the whole year. After the onset of SCS summer monsoon, southwesterly monsoon flow and monsoon rainbelt prevail from Indian Ocean through Bay of Bengal and SCS to northwest Pacific which is a mark of summer monsoon onset over both South Asia and East Asia.