热带偶极型对流活动与东亚夏季风的联系  

Relationship between the dipole tropical convective activities and east Asian summer monsson

作　　者：刘宣飞[1] 励申申[1] 唐镭[2] 

机构地区：[1]南京气象学院大气科学系,南京210044 [2]南京气象学院气象台,南京210044

出　　处：《南京气象学院学报》2000年第3期323-329,共7页Journal of Nanjing Institute of Meteorology

基　　金：国家自然科学基金!重点项目 4 963 51 80资助

摘　　要：采用 1 979～ 1 994年 NCEP/NCAR再分析风场资料和 OL R资料 ,研究了热带对流的变化特征 ,讨论了热带对流年际变化与东亚夏季风的关联。指出 :夏季热带对流存在以西太平洋暖池附近和赤道中太平洋附近为中心的年际变化方差大值区 ,且这两个中心的对流变化呈偶极型反位相振荡 ,这种偶极型对流活动与东亚夏季风有密切关系。当暖池附近对流偏强 (弱 ) ,赤道中太平洋附近对流偏弱 (强 )时 ,东亚夏季风偏强 (弱 ) ,雨带偏北 (南 ) ,长江流域少 (多 )雨。进一步分析表明 :热带偶极型对流活动主要与东亚热带外地区的正压型大气环流异常相联系 ,而热带太平洋地区的大气环流主要表现为斜压型异常。In terms of 1979~1994 NCEP/NCAR re analyses and OLR data,the variation characteristics of tropical convective activities are investigated and the relationships between the interannual variation of summer OLR and East Asian summer monsoon(EASM) are discussed.It is found that the interannual variation of summer OLR is remarkable in warm pool and the equatorial central Pacific,which is in anti phase oscillation. When the convective activities are strong(weak) in warm pool and weak(strong) in the equatorial central Pacific, the EASM is strong(weak) and the rainbelt is north(south) of its mean position with less(more) precipitation in the Yangtze River reaches.Further evidences show that the atmospheric circulation anomaly in subtropical Asia(tropical Pacific) relative to the dipole tropical convective activities is vertically barotropic(baroclinic).

关 键 词：热带对流 偶极型变化 东亚夏季风 大气环流 

分 类 号：P434[天文地球—大气科学及气象学]