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	<journal>
		<journal_title>Atmospheric Chemistry and Physics</journal_title>
		<journal_url>www.atmos-chem-phys.net</journal_url>
		<issn>1680-7316</issn>
		<eissn>1680-7324</eissn>
		<volume_number>9</volume_number>
		<issue_number>5</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/acp-9-1621-2009</doi>
	<article_url>http://www.atmos-chem-phys.net/9/1621/2009/</article_url>
	<abstract_html>http://www.atmos-chem-phys.net/9/1621/2009/acp-9-1621-2009.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys.net/9/1621/2009/acp-9-1621-2009.pdf</fulltext_pdf>
	<start_page>1621</start_page>
	<end_page>1637</end_page>
	<publication_date>2009-03-04</publication_date>
	<article_title content_type="html">The Tropical Tropopause Layer 1960–2100</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>A. Gettelman</name>
			<email>andrew@ucar.edu</email>
		</author>
		<author numeration="2" affiliations="2">
			<name>T. Birner</name>
		</author>
		<author numeration="3" affiliations="3">
			<name>V. Eyring</name>
		</author>
		<author numeration="4" affiliations="4">
			<name>H. Akiyoshi</name>
		</author>
		<author numeration="5" affiliations="6">
			<name>S. Bekki</name>
		</author>
		<author numeration="6" affiliations="8">
			<name>C. Brühl</name>
		</author>
		<author numeration="7" affiliations="3">
			<name>M. Dameris</name>
		</author>
		<author numeration="8" affiliations="1">
			<name>D. E. Kinnison</name>
		</author>
		<author numeration="9" affiliations="6">
			<name>F. Lefevre</name>
		</author>
		<author numeration="10" affiliations="7">
			<name>F. Lott</name>
		</author>
		<author numeration="11" affiliations="11">
			<name>E. Mancini</name>
		</author>
		<author numeration="12" affiliations="11">
			<name>G. Pitari</name>
		</author>
		<author numeration="13" affiliations="5">
			<name>D. A. Plummer</name>
		</author>
		<author numeration="14" affiliations="10">
			<name>E. Rozanov</name>
		</author>
		<author numeration="15" affiliations="9">
			<name>K. Shibata</name>
		</author>
		<author numeration="16" affiliations="3">
			<name>A. Stenke</name>
		</author>
		<author numeration="17" affiliations="12">
			<name>H. Struthers</name>
		</author>
		<author numeration="18" affiliations="13">
			<name>W. Tian</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">National Center for Atmospheric Research, Boulder, CO, USA</affiliation>
		<affiliation numeration="2" content_type="html">University of Toronto, Toronto, ON, Canada</affiliation>
		<affiliation numeration="3" content_type="html">Deutsches Zentrum für Luft- und Raumfahrt, Oberpfaffenhofen, Germany</affiliation>
		<affiliation numeration="4" content_type="html">National Institute for Environmental Studies, Tsukuba, Japan</affiliation>
		<affiliation numeration="5" content_type="html">Canadian Centre for Climate Modeling and Analysis, Victoria, BC, Canada</affiliation>
		<affiliation numeration="6" content_type="html">Université Pierre and Marie Curie, Service d&apos;Aeronomie, Paris, France</affiliation>
		<affiliation numeration="7" content_type="html">L&apos;Institut Pierre-Simon Laplace, Ecole Normale Superieur, Paris, France</affiliation>
		<affiliation numeration="8" content_type="html">Max Planck Institut für Chemie, Mainz, Germany</affiliation>
		<affiliation numeration="9" content_type="html">Meteorological Research Institute, Tsukuba, Japan</affiliation>
		<affiliation numeration="10" content_type="html">Physikalisch-Meteorologisches Observatorium Davos, Davos, Switzerland</affiliation>
		<affiliation numeration="11" content_type="html">Universita degli Studi de L&apos;Aquila, L&apos;Aquila, Italy</affiliation>
		<affiliation numeration="12" content_type="html">National Institute for Water and Atmosphere, New Zealand</affiliation>
		<affiliation numeration="13" content_type="html">University of Leeds, Leeds, UK</affiliation>
	</affiliations>
	<abstract content_type="html">The representation of the Tropical Tropopause Layer (TTL) in
13 different Chemistry Climate Models (CCMs) designed to represent
the stratosphere
is analyzed. Simulations for 1960–2005 and 1980–2100 are analyzed.
Simulations for 1960–2005 are compared to reanalysis model output.
CCMs are able to reproduce the basic structure of
the TTL. There is a large (10 K) spread in annual mean tropical cold point
tropopause temperatures.
CCMs are able to reproduce historical trends in
tropopause pressure obtained from reanalysis products.
Simulated historical trends in cold point tropopause
temperatures are not consistent across models or reanalyses.
The pressure of both the tropical tropopause and the level of main
convective outflow appear to have decreased (increased altitude)
in historical runs as well as in reanalyses.
Decreasing pressure trends in the tropical tropopause and level of
main convective
outflow are also seen in the future. Models consistently predict
decreasing tropopause and convective outflow pressure, by
several hPa/decade.  Tropical cold point temperatures are projected to increase
by 0.09 K/decade. Tropopause anomalies
are highly correlated with tropical surface temperature anomalies and
with tropopause level ozone anomalies, less so with stratospheric
temperature anomalies. Simulated stratospheric water vapor at 90 hPa
increases by up to 0.5–1 ppmv by 2100.
The result is consistent with the simulated increase in
temperature, highlighting the correlation of tropopause
temperatures with stratospheric water vapor.</abstract>
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