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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACP</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACP</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7324</issn>
<publisher><publisher-name>Copernicus GmbH</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-7-107-2007</article-id>
<title-group>
<article-title>The water vapour distribution in the Arctic lowermost stratosphere during the LAUTLOS campaign and related transport processes including stratosphere-troposphere exchange</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Karpechko</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lukyanov</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kyrö</surname>
<given-names>E.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Khaikin</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Korshunov</surname>
<given-names>L.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kivi</surname>
<given-names>R.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Vömel</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Finnish Meteorological Institute, ARC, Sodankylä, Finland</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Central Aerological Observatory, Moscow, Russia</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Cooperative Institute for Environmental Sciences, University of Colorado, Boulder, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>10</day>
<month>01</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>1</issue>
<fpage>107</fpage>
<lpage>119</lpage>
<permissions>
<license xlink:type="simple">
<license-p>This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</license-p>
</license>
</permissions>
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<self-uri xlink:href="http://www.atmos-chem-phys.net/7/107/2007/acp-7-107-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/107/2007/acp-7-107-2007.pdf</self-uri>
<abstract>
<p>Balloon-borne water vapour measurements during January and February 2004,
which were obtained as part of the LAUTLOS campaign at Sodankylä,
Finland, 67&amp;deg; N, were used to analyse the water vapour distribution in the
wintertime Arctic lowermost stratosphere. A 2.5 km thick layer (or 30 K in
the potential temperature scale) above the tropopause is characterized by a
significant water vapour variability on a synoptic timescale with values
between stratospheric and tropospheric, which is in good agreement with
previously reported measurements. A cross-correlation analysis of ozone and
water vapour confirms that this layer contains a mixture of stratospheric
and tropospheric air masses. Some of the flights sampled laminae of enhanced
water vapour above the tropopause. Meteorological analyses and backward
trajectory calculations show that these features were related to filaments
that had developed along the flanks of cut-off anticyclones, which had been
active at this time over the Northern Atlantic. The role of the filaments
was however not to transport water vapour from the troposphere to the
stratosphere but rather to transport it within the stratosphere away from
regions where intensive two-way stratosphere-troposphere exchange (STE) was
identified. Intensive STE occurred around cut-off anticyclones in regions of
strong winds, where calculations suggest the presence of clear-air
turbulence (CAT). Evidences that CAT contributes to the
troposphere-to-stratosphere transport (TST) are presented. However,
statistically, relation between TST and CAT during the studied period is
weak.</p>
</abstract>
<counts><page-count count="13"/></counts>
</article-meta>
</front>
<body/>
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