Features of the Western Pacific Subtropical High during the Warm and Cool Periods of Nino 1+2 Area and Its influence on the East Asian Monsoon
Ni?o 1+2海区冷、暖水期西太平洋副高的特征及其对东亚季风的影响

Abstract Based on the data of geopolential height and vertical velocity of 500 hPa, wind field of 850 hPa and SST, the features of the western Pacific subtropical high and the east Asian monsoon at different stage of ENSO arc discussed. The results show that there is a close relationship between the western Pacific subtropical high and SST in the eastern equatorial Pacific. The decade variations of SST in Nino 1+2 area is coincident with the variations of the western Pacific subtropical high. The strength and position of the western Pacific subtropical high in the period following warm SST in Nino 1+2 area are very different from those in the period following cool Nino 1+2 SST. In ihc period following the warm SST, the western Pacific subtropical high is stronger, extends westward and southward, while it is reverse in the period following the cool SST, The subtropical high is weaker and its location is usually to the north and east. The changes of the western Pacific subtropical high will impact the Asian monsoon and the precipitation of China. These influences are clearest in 4-6 months after the SST in Nino 1+2 area is changed. Therefore, the variations of SST in Nino 1+2 area of the previous period can be a basis for the long-term prediction of the western Pacific subtropical high and the east Asian monsoon.