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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>GÃ¶ttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-7-685-2007</article-id>
<title-group>
<article-title>Solid particles in the tropical lowest stratosphere</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Nielsen</surname>
<given-names>J. K.</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>Larsen</surname>
<given-names>N.</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>Cairo</surname>
<given-names>F.</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>Di Donfrancesco</surname>
<given-names>G.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rosen</surname>
<given-names>J. M.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Durry</surname>
<given-names>G.</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Held</surname>
<given-names>G.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Pommereau</surname>
<given-names>J. P.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Danish Meteorological Institute, Lyngbyvej 100, 2100 Kbh. Ã˜, Denmark</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Institute for Atmospheric Science and Climate, CNR, Via del Fosso del Cavaliere 100, 00133 Rome, Italy</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Italian National Agency for New Technologies, Energy and Environment, ENEA C. R. Cassaccia, Via Anguillarese 301, 00060 Rome, Italy</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>University of Wyoming, Department of Physics and Astronomy, Laramie, Wyoming 82071, USA</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Groupe de Spectrometrie Moleculaire et Atmospherique, CNRS, Universite de Reims , 51687 Reims, France</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Instituto de Pesquisas MeteorolÃ³gicas, Universidade Estadual Paulista, CX Postal, 281 17015-970 BAURU, S. P., Brasil</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>CNRS, Institut Pierre Simon Laplace, Service d&apos;Aeronomie, B.P. 3, 91371 Verrieres le Buisson Cedex, France</addr-line>
</aff>
<pub-date pub-type="epub">
<day>12</day>
<month>02</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>3</issue>
<fpage>685</fpage>
<lpage>695</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>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/685/2007/acp-7-685-2007.html">This article is available from http://www.atmos-chem-phys.net/7/685/2007/acp-7-685-2007.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/685/2007/acp-7-685-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/685/2007/acp-7-685-2007.pdf</self-uri>
<abstract>
<p>We report in situ and remote observations proving occasional
occurrence of solid particles in the tropical lowest stratosphere,
200 km from deep convective events. The particles were found
during field campaigns in Southeast Brazil (49.03 W 22.36 S). They
occur in the altitude range from 17.5 to 20.8 km, at temperatures up
to at least 10 K above the expected frost point temperature. While
stability of ice particles at these altitudes is unexpected from a
theoretical point of view, it is argued that these observations are
indications of tropospheric air masses penetrating into the
stratosphere during convective overshoots. It is
argued that the intrusion of tropospheric air must have carried a
large amount of water with it, which effectively hydrated the lowest
stratosphere, and consequently suppressed sublimation. This
conclusion is further supported by a separate water vapor mixing
ratio profile obtained at the same observation site.</p>
</abstract>
<counts><page-count count="11"/></counts>
</article-meta>
</front>
<body/>
<back>
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