The Zonal Structure of the Hadley Circulation  

作　　者：Peter G.BAINES 

机构地区：[1]Department of Civil and Environmental Engineering, University of Melbourne,Melbourne,Australia 3010 Quantifying and Understanding the Earth System (QUEST),Department of Earth Sciences,University of Bristol,Bristol BS8 1RJ,UK

出　　处：《Advances in Atmospheric Sciences》2006年第6期869-883,共15页大气科学进展（英文版）

摘　　要：A discussion of the mass transport of the Hadley circulation is presented, with regard to its longitudinal structure. Data from the NCEP/NCAR reanalysis data set for the period 1948-2005 is examined, focusing on the solsticial seasons of June-August and December-February. Quantitative estimates have been extracted from the data to observe connections between the zonal mean of the upper tropospheric north/south mass transports and their relationship to the driving factor of tropical precipitation （implying latent heat release） and subsidence in the subtropical high pressure belts. The longitudinal structure of this flow is then examined with regard to these three main variables. The poleward upper tropospheric transport has four （JJA） or three （DJF） main branches, which link regions of major precipitation with corresponding regions of large subsidence, and one （June, July, August） or two （December, January, February） reverse branches. This structure has remained stable over the past sixty years. Although the total upper tropospheric transport in each season is less than the total sinking transport in the target subtropical high pressure belt, this does not apply to the individual branches, the balance being made up by the upper tropospheric reverse transports. An analysis of correlations between all of these various components shows, however, that the complete picture is more complex, with some precipitation regions being linked to subsidence regions outside their own branch.A discussion of the mass transport of the Hadley circulation is presented, with regard to its longitudinal structure. Data from the NCEP/NCAR reanalysis data set for the period 1948-2005 is examined, focusing on the solsticial seasons of June-August and December-February. Quantitative estimates have been extracted from the data to observe connections between the zonal mean of the upper tropospheric north/south mass transports and their relationship to the driving factor of tropical precipitation （implying latent heat release） and subsidence in the subtropical high pressure belts. The longitudinal structure of this flow is then examined with regard to these three main variables. The poleward upper tropospheric transport has four （JJA） or three （DJF） main branches, which link regions of major precipitation with corresponding regions of large subsidence, and one （June, July, August） or two （December, January, February） reverse branches. This structure has remained stable over the past sixty years. Although the total upper tropospheric transport in each season is less than the total sinking transport in the target subtropical high pressure belt, this does not apply to the individual branches, the balance being made up by the upper tropospheric reverse transports. An analysis of correlations between all of these various components shows, however, that the complete picture is more complex, with some precipitation regions being linked to subsidence regions outside their own branch.

关 键 词：Hadley circulation PRECIPITATION SUBSIDENCE horizontal and vertical transport 

分 类 号：P434[天文地球—大气科学及气象学]