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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACPD</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACPD</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7375</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/acpd-11-11809-2011</article-id>
<title-group>
<article-title>Night-time enhanced atmospheric ion concentrations in the marine boundary layer</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kalivitis</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>Stavroulas</surname>
<given-names>I.</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>Bougiatioti</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>Kouvarakis</surname>
<given-names>G.</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>Gagné</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>Manninen</surname>
<given-names>H. E.</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>Kulmala</surname>
<given-names>M.</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>Mihalopoulos</surname>
<given-names>N.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Environmental Chemical Processes Laboratory, Department of Chemistry,  University of Crete, 71003, Heraklion, Greece</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>15</day>
<month>04</month>
<year>2011</year>
</pub-date>
<volume>11</volume>
<issue>4</issue>
<fpage>11809</fpage>
<lpage>11837</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-discuss.net/11/11809/2011/acpd-11-11809-2011.html">This article is available from http://www.atmos-chem-phys-discuss.net/11/11809/2011/acpd-11-11809-2011.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/11/11809/2011/acpd-11-11809-2011.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/11809/2011/acpd-11-11809-2011.pdf</self-uri>
<abstract>
<p>Measurements of atmospheric ions in the size range 0.8–42 nm were
      conducted at the environmental research station of the University of
      Crete at Finokalia from April 2008 to April 2009 in the frame of the
      EUCAARI project. Both positive and negative atmospheric ions were
      found to have a clear annual cycle, with minimum concentrations in
      summer. Their concentrations were found to strongly vary on the
      prevailing meteorology and the presence of pollutants in the
      atmosphere. There were 53 new particle formation events recorded. It
      was found that under certain meteorological conditions and atmospheric
      composition, enhanced ion concentrations can be observed during the
      night. Overall, 39 night-time events were observed, all of them
      observed for the negatively charged particles while only 21 were
      observed for the positively charged particles. Night-time enhanced ion
      concentrations were more frequent during spring and autumn and no such
      events were recorded from July to September. It was found that the
      presence of pollutants in the atmosphere leads to a decrease of
      atmospheric ions, especially at cluster sizes
      (1.25–1.66 nm). Additionally, the meteorological conditions affect
      the abundance of atmospheric ions greatly, a strong anti-correlation
      was found between air ions concentrations on the one hand and
      temperature and wind velocity on the other. Enhanced ion
      concentrations at night were found to be more frequent when air masses
      had traveled over the island of Crete.</p>
</abstract>
<counts><page-count count="29"/></counts>
</article-meta>
</front>
<body/>
<back>
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