Observational Evidence for Poleward Expansion of the Hadley Circulation  

作　　者：胡永云 周晨 刘骥平 

机构地区：[1]Department of Atmospheric and Oceanic Sciences,School of Physics,Peking University [2]Laboratory for Climate and Ocean-Atmosphere Studies,Peking University [3]State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics

出　　处：《Advances in Atmospheric Sciences》2011年第1期33-44,共12页大气科学进展（英文版）

基　　金：supported by the National Natural Science Foundation of China (40875042, 41025018);the National Basic Research Program of China (2007CB411801);the Ministry of Education of China (20070001002);J Liu is supported by the National Basic Research Program of China(2006CB403605);NSFC (40876099)

摘　　要：How the Hadley circulation changes in response to global climate change and how its change impacts upon regional and global climates has generated a lot of interest in the literature in the past few years. In this paper, consistent and statistically significant poleward expansion of the Hadley circulation in the past few decades is demonstrated, using independent observational datasets as proxy measures of the Hadley circulation. Both observational outgoing longwave radiation and precipitation datasets show an annual average total poleward expansion of the Hadley cells of about 3.6° latitude. Sea level pressure from observational and reanalysis datasets show smaller magnitudes of poleward expansion, of about 1.2° latitude. Ensemble general circulation model simulations forced by observed time-varying sea surface temperatures were found to generate a total poleward expansion of about 1.23°latitude. Possible mechanisms behind the changes in the horizontal extent of the Hadley circulation are discussed.How the Hadley circulation changes in response to global climate change and how its change impacts upon regional and global climates has generated a lot of interest in the literature in the past few years. In this paper, consistent and statistically significant poleward expansion of the Hadley circulation in the past few decades is demonstrated, using independent observational datasets as proxy measures of the Hadley circulation. Both observational outgoing longwave radiation and precipitation datasets show an annual average total poleward expansion of the Hadley cells of about 3.6° latitude. Sea level pressure from observational and reanalysis datasets show smaller magnitudes of poleward expansion, of about 1.2° latitude. Ensemble general circulation model simulations forced by observed time-varying sea surface temperatures were found to generate a total poleward expansion of about 1.23°latitude. Possible mechanisms behind the changes in the horizontal extent of the Hadley circulation are discussed.

关 键 词：Hadley circulation outgoing longwave radiation PRECIPITATION sea level pressure climate change 

分 类 号：P467[天文地球—大气科学及气象学]