Extended Abstract

negative in the northern hemisphere, it leads the convergence of warm water over equatorialregion and influences the distribution of the heat flux. As a result, the equatorial easternPacific sea temperature will rise and trigger the El Niño onset. Fig. 2 shows the differencesof the physical fields between the strong subtropical high years and weak subtropical highyears. Fig. 2a is the composite diagram of the fields’ differences under the (JJA0) anomalyin Figure 1b. Fig. 2b and 2c are the surface wind stress and the ocean surface current fieldanomalies respectively in the summer before the onset of El Niño when the SLP subtropicalhigh appears changes.(a) (b) (c)Fig. 2. The composite of summertime (a) surface wind anomaly、(b) surface wind stress anomaly and (c) the ocean surfacecurrent anomaly in the El Nino developing year.References:[1] ZHU Cong-wen, He Jin-hai, Tan Yan-ke. Characteristics of the northern hemispheresub-tropical high seasonal splitting over the Asian monsoon sectors and its possiblemechanism [J]. J. Trop. Meteor., 2004, 10(02): 160-170.[2] CHEN Lie-ting, WU Ren-guang. The joint effects of SST anomalies over different Pacificregions on summer rainbelt patterns in eastern China [J]. Chinese Journal ofAtmospheric Sciences, 1998,22(05):43-51[3] WANG Xiao-chun, WU Guo-xiong. The analysis of the relationship between the spatialmodes of summer precipitation anomalies over China and the general circulation [J].Chinese Journal of Atmospheric Sciences, 1997,21(2):161-169[4] YU Dan-dan, Zhang Ren, Hong Mei et al. A characteristic correlation analysis betweenthe Asia summer monsoon memberships and west Pacific subtropical high [J]. J. Trop.Meteor., 2007, 23(1):78-84[5] CAI Xue-zhan, Wen Zhen-zhi, Wu Bin. Relationship between west Pacific subtropicalhigh and ENSO and its influence on rainfall distribution of rainy season in FUJIAN [J]. J.Trop. Meteor., 2003,19(1):36-42[6] YANG Xiu-qun, Guo Yan-juan, Xu Gui-yu et al. Comparison of global spation-temporalstructures between interannual and interdecadal climate variations [J]. Journal ofNANJING university (natural sciences), 2002, 38(3):308-317[7] TORRENCE C,WEBSTER P J. Interdecadal changes in the ENSO-Monsoon system [J].J Climate, 1999, 12(8): 2679-2690.-429-