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<article language="en">
	<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>8</volume_number>
		<issue_number>3</issue_number>
		<publication_year>2008</publication_year>
	</journal>
	<doi>10.5194/acp-8-505-2008</doi>
	<article_url>http://www.atmos-chem-phys.net/8/505/2008/</article_url>
	<abstract_html>http://www.atmos-chem-phys.net/8/505/2008/acp-8-505-2008.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys.net/8/505/2008/acp-8-505-2008.pdf</fulltext_pdf>
	<start_page>505</start_page>
	<end_page>522</end_page>
	<publication_date>2008-02-06</publication_date>
	<article_title content_type="html">The high Arctic in extreme winters: vortex, temperature, and MLS and ACE-FTS trace gas evolution</article_title>
	<authors>
		<author numeration="1" affiliations="1,2">
			<name>G. L. Manney</name>
			<email>manney@mls.jpl.nasa.gov</email>
		</author>
		<author numeration="2" affiliations="3">
			<name>W. H. Daffer</name>
		</author>
		<author numeration="3" affiliations="4">
			<name>K. B. Strawbridge</name>
		</author>
		<author numeration="4" affiliations="5,6">
			<name>K. A. Walker</name>
		</author>
		<author numeration="5" affiliations="6">
			<name>C. D. Boone</name>
		</author>
		<author numeration="6" affiliations="6,7">
			<name>P. F. Bernath</name>
		</author>
		<author numeration="7" affiliations="5">
			<name>T. Kerzenmacher</name>
		</author>
		<author numeration="8" affiliations="1">
			<name>M. J. Schwartz</name>
		</author>
		<author numeration="9" affiliations="5">
			<name>K. Strong</name>
		</author>
		<author numeration="10" affiliations="8">
			<name>R. J. Sica</name>
		</author>
		<author numeration="11" affiliations="9">
			<name>K. Krüger</name>
		</author>
		<author numeration="12" affiliations="10">
			<name>H. C. Pumphrey</name>
		</author>
		<author numeration="13" affiliations="1">
			<name>A. Lambert</name>
		</author>
		<author numeration="14" affiliations="1">
			<name>M. L. Santee</name>
		</author>
		<author numeration="15" affiliations="1">
			<name>N. J. Livesey</name>
		</author>
		<author numeration="16" affiliations="11">
			<name>E. E. Remsberg</name>
		</author>
		<author numeration="17" affiliations="11">
			<name>M. G. Mlynczak</name>
		</author>
		<author numeration="18" affiliations="12">
			<name>J. R. Russell III</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA</affiliation>
		<affiliation numeration="2" content_type="html">Department of Physics, New Mexico Institute of Mining and Technology, Socorro, NM, USA</affiliation>
		<affiliation numeration="3" content_type="html">Columbus Technologies Inc., Pasadena, CA, USA</affiliation>
		<affiliation numeration="4" content_type="html">Science and Technology Branch, Environment Canada, Ontario, Canada</affiliation>
		<affiliation numeration="5" content_type="html">Department of Physics, University of Toronto, Toronto, Ontario, Canada</affiliation>
		<affiliation numeration="6" content_type="html">Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada</affiliation>
		<affiliation numeration="7" content_type="html">Department of Chemistry, University of York, Heslington, York, UK</affiliation>
		<affiliation numeration="8" content_type="html">Department of Physics and Astronomy, The University of Western Ontario, London, Ontario, Canada</affiliation>
		<affiliation numeration="9" content_type="html">Leibniz-Institute for Marine Sciences at Kiel University (IFM-GEOMAR), Kiel, Germany</affiliation>
		<affiliation numeration="10" content_type="html">School of Geosciences, University of Edinburgh, Edinburgh, UK</affiliation>
		<affiliation numeration="11" content_type="html">NASA Langley Research Center, Hampton, VA, USA</affiliation>
		<affiliation numeration="12" content_type="html">Atmospheric and Planetary Sciences, Hampton University, Hampton, VA, USA</affiliation>
	</affiliations>
	<abstract content_type="html">The first three Arctic winters of the ACE mission
represented two extremes of winter variability:
Stratospheric sudden warmings (SSWs) in 2004 and 2006 were among the strongest,
most prolonged on record; 2005 was a record cold
winter. Canadian Arctic Atmospheric Chemistry Experiment (ACE)
Validation Campaigns were conducted at Eureka (80&amp;deg; N, 86&amp;deg; W)
during each of these winters. New satellite measurements from ACE-Fourier Transform Spectrometer (ACE-FTS),
Sounding of the Atmosphere using Broadband Emission Radiometry (SABER),
and Aura Microwave Limb Sounder (MLS), along with
meteorological analyses and Eureka lidar temperatures,
are used to detail the meteorology in these winters, to
demonstrate its influence on transport, and to provide a
context for interpretation of ACE-FTS and validation campaign observations.
During the 2004 and 2006 SSWs, the vortex broke down throughout
the stratosphere, reformed quickly in the upper stratosphere, and remained
weak in the middle and lower stratosphere.
The stratopause reformed at very high altitude, near 75 km.
ACE measurements covered both vortex and extra-vortex conditions
in each winter, except in late-February through mid-March 2004 and 2006, when the
strong, pole-centered vortex that reformed after the SSWs resulted in ACE
sampling only inside the vortex in the middle through upper stratosphere.
The 2004 and 2006 Eureka campaigns were during the recovery
from the SSWs, with the redeveloping vortex over Eureka.
2005 was the coldest winter on record in the lower
stratosphere, but with an early final warming in mid-March.
The vortex was over Eureka at the start of the 2005 campaign,
but moved away as it broke up. Disparate
temperature profile structure and vortex evolution resulted in
much lower (higher) temperatures in the upper (lower) stratosphere
in 2004 and 2006 than in 2005.  Satellite temperatures agree well
with lidar data up to 50&amp;ndash;60 km, and ACE-FTS, MLS and SABER show good agreement in high-latitude
temperatures throughout the winters.  Consistent with a strong, cold upper
stratospheric vortex and enhanced radiative cooling after the SSWs,
MLS and ACE-FTS trace gas measurements show strongly enhanced descent in the
upper stratospheric vortex in late January through March 2006
compared to that in 2005.</abstract>
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