ANOMALIES OF THE BACKGROUND CIRCULATION OF THE IAP GCM MODEL ATMOSPHERE IN AN EL NINO YEAR

Analysis is performed of the May-September mean circulation,referred to as the background circulation hereinafter,in the IAP(Institute of Atmospheric Physics,Academia Sinica)GCM model atmosphere,It is found that in an El Nino year there occur anomalies in a set of major systems,e.g.,Southetm Oscillation,Walker and Hadley circulations,the western Pacific subtropical high and ITCZ,2nd in large-scale precipitation,with their happening dominantly in the Northern Hemisphere tropical and subtropical latitudes in the western Pacific.These results that are in rough agreement with the analyzed actual observations demonstrate the applicabilities of the model to the study of low-latitude circulations.