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GEOPHYSICAL RESEARCH LETTERS,
VOL. 34,
L18804,
doi:10.1029/2007GL031115,
2007
Width of the Hadley cell in simple and comprehensive general circulation models
Dargan M. W. Frierson
Department of Geophysical Sciences, University of Chicago, Chicago, Illinois, USA
Jian Lu
National Center for Atmospheric Research, Boulder, Colorado, USA
Gang Chen
Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, New Jersey, USA
Abstract
The width of the Hadley cell is studied over a wide range of climate regimes using both simple and comprehensive atmospheric
general circulation models. Aquaplanet, fixed sea surface temperature lower boundary conditions are used in both models to
study the response of the Hadley cell width to changes in both global mean temperature and pole-to-equator temperature gradient.
The primary sensitivity of both models is a large expansion of the Hadley cell with increased mean temperature. The models
also exhibit a smaller increase in width with temperature gradient. The Hadley cell widths agree well with a scaling theory
by Held which assumes that the width is determined by the latitude where baroclinic eddies begin to occur. As surface temperatures
are warmed, the latitude of baroclinic instability onset is shifted poleward due to increases in the static stability of the
subtropics, which is increased in an atmosphere with higher moisture content.
Received 24
June
2007;
accepted 17
August
2007;
published 19
September
2007.
Keywords: Hadley;
dynamics;
moisture.
Index Terms: 1610 Global Change: Atmosphere (0315, 0325); 1626 Global Change: Global climate models (3337, 4928); 3319 Atmospheric Processes: General circulation (1223).
Read Full Article (file size: 137765 bytes) Cited by
Citation: Frierson, D. M. W., J. Lu, and G. Chen
(2007),
Width of the Hadley cell in simple and comprehensive general circulation models,
Geophys. Res. Lett.,
34,
L18804,
doi:10.1029/2007GL031115.
Copyright 2007 by the American Geophysical Union.
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