Global Response to Tropical Diabatic Heating Variability in Boreal Winter  

作　　者：张 旭 Hai LINt 江 静 

机构地区：[1]School of Atmospheric Sciences, Nanjing University, Nanjing 210093 [2]Shanghai Typhoon Institute, Chinese Meteorological Administration, Shanghai 200030 [3]Meteorological Research Division, Environmental Canada, Dorval, Quebec, Canada

出　　处：《Advances in Atmospheric Sciences》2012年第2期369-380,共12页大气科学进展（英文版）

基　　金：partly supported by the Canadian Foundation for Climate and Atmospheric Sciences (CFCAS);the Natural Sciences and Engineering Research Council of Canada (NSERC);support from the National Key Technology R&D Program of China (Grant No 2009BAC51B01)

摘　　要：Global teleconnections associated with tropical convective activities were investigated, based on monthly data of 29 Northern Hemisphere winters： December, January, February, and March （DJFM）. First, EOF analyses were performed on the outgoing longwave radiation （OLR） data to characterize the convective ac tivity variability in the tropical Indian Ocean and the western Pacific. The first EOF mode of the convective activity was highly correlated with the ENSO. The second EOF mode had an east–west dipole structure, and the third EOF mode had three convective activity centers. Two distinct teleconnection patterns were identified that were associated, respectively, with the second and third EOF modes. A global primitive equation model was used to investigate the physical mechanism that causes the global circulation anoma lies. The model responses to anomalous tropical thermal forcings that mimic the EOF patterns matched the general features of the observed circulation anomalies well, and they were mainly controlled by linear processes. The importance of convective activities in the tropical Indian Ocean and western Pacific to the extended and longrange forecasting capability in the extratropics is discussed.Global teleconnections associated with tropical convective activities were investigated, based on monthly data of 29 Northern Hemisphere winters： December, January, February, and March （DJFM）. First, EOF analyses were performed on the outgoing longwave radiation （OLR） data to characterize the convective ac tivity variability in the tropical Indian Ocean and the western Pacific. The first EOF mode of the convective activity was highly correlated with the ENSO. The second EOF mode had an east–west dipole structure, and the third EOF mode had three convective activity centers. Two distinct teleconnection patterns were identified that were associated, respectively, with the second and third EOF modes. A global primitive equation model was used to investigate the physical mechanism that causes the global circulation anoma lies. The model responses to anomalous tropical thermal forcings that mimic the EOF patterns matched the general features of the observed circulation anomalies well, and they were mainly controlled by linear processes. The importance of convective activities in the tropical Indian Ocean and western Pacific to the extended and longrange forecasting capability in the extratropics is discussed.

关 键 词：diabatic heating TELECONNECTION tropical convective activities 

分 类 号：P433[天文地球—大气科学及气象学]