Simulation Analysis to the Relationship between the Distribution Characteristic of SAH and the Precipitation of Yangtze River Valley

Based on the NCEP/NCAR monthly mean reanalysis-2 dataset from 1979 to 2008 and the observational monthly mean data at stations given by National Climate Center, it studies the inter-decadal variations and the relation of South Asia high (SAH) .It is found that all of the parameters of SAH exist the remarkably inter-decadal variations in summer.Before the 1991, the area index is larger, the intensity index is stronger, the east ridge point and center position of SAH is more east.After 1991, the parameters of SAH present reverse variety.The correlation analysis indicates that the area index, the intensity and east ridge point of SAH exist significant relation.This paper uses RegCM3 to simulate the situation of 1996 and 1998, which are the east ridge point of SAH representative abnormity year.Through simulation, this paper analyzes the ability of simulating precipitation of this model.The results indicate that the center of precipitation can be simulated, but the intensity of the precipitation is smaller by simulating.