A NUMERICAL SIMULATION OF THE EFFECT OF GLOBAL SSTA ON THE LOW-LEVEL ATMOSPHERIC CIRCULATION AND PRECIPITATION ANOMALIES

By the numerical simulation,the sea surface temperature anomaly(SSTA)of the Pacific and Indian Oceans.being introduced into IAP AGCM,the observed anomalous circulation characteristics on the monthly mean 850 hPa have been confirmed:during an El Nino episode there appears anomalous westerly flow in the low-level atmosphere over the low-latitude Pacific and the anomalous equatorward air flow over the Southeast Asia coast:during a La Nina episode there appears anomalous easterly flow in the low-level atmosphere over the low-latitude Pacific and the anomalous off-equator air flow over the Southeast Asia coast.If we introduce only Pacific SSTA into or take off orographic forcing from the model,the simulated anomalous air flow in the low- level atmosphere over the low latitudes will be different.The precipitation departure in conformity with the observation over the low latitudes has been simulated with this model as well.