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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-9-905-2009</article-id>
<title-group>
<article-title>Surface ozone at the Caucasian site Kislovodsk High Mountain Station and the  Swiss Alpine site Jungfraujoch: data analysis and trends (1990&amp;ndash;2006)</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Tarasova</surname>
<given-names>O. A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Senik</surname>
<given-names>I. A.</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>Sosonkin</surname>
<given-names>M. G.</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>Cui</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Staehelin</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Prévôt</surname>
<given-names>A. S. H.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Max-Planck Institute for Chemistry, Mainz, Germany</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Moscow State  University, Moscow, Russia</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Obukhov Institute of Atmosphere Physics RAS, Moscow, Russia</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>International Center for Astronomical, Medical and Ecological  Research NAS, Kiev, Ukraine</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Institute for Atmospheric and Climate Science, Swiss Federal  Institute of Technology Zürich, Switzerland</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Paul Scherrer Institute, Villigen, Switzerland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>13</day>
<month>01</month>
<year>2009</year>
</pub-date>
<volume>9</volume>
<issue>1</issue>
<fpage>905</fpage>
<lpage>954</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-discuss.net/9/905/2009/acpd-9-905-2009.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/9/905/2009/acpd-9-905-2009.pdf</self-uri>
<abstract>
<p>Long-term ozone measurements of two background mountain sites, namely
      the Kislovodsk High Mountain Station in Caucasus, Russia (KHMS,
      43.70&amp;deg; N, 42.70&amp;deg; E, 2070 m a.s.l.)
      and the Jungfraujoch in Switzerland (JFJ, 46.55&amp;deg; N,
      7.98&amp;deg; E, 3580 m a.s.l.) are compared. Despite of
      more than 1.5 km altitude difference ozone concentrations are
      comparable at JFJ an KHMS in the beginning of measurements
      (1990–1993) while the annually averaged levels at JFJ are around
      15 ppb higher than the ones at KHMS for the most recent years
      (1997–2006). Averaged for different periods ozone concentrations at
      KHMS are comparable with the respective values observed at the
      elevated sites in the midlatitudes, situated in the altitude range
      1600–2400 m a.s.l. Distribution function of the hourly
      concentrations has two peaks at JFJ and it is close to Gaussian distribution
      in the case of KHMS. Seasonality at both sites is characterized by
      double spring-summer maximum. Spring maximum at both stations is more
      pronounced for the air masses with the longest contact with upper free
      troposphere and stratosphere. Average concentrations increased at JFJ
      but decreased at KHMS for the period 1990–2006. Trends are more
      pronounced for the 1990s (+0.73&amp;plusmn;0.20 ppb/year at JFJ
      and &amp;minus;0.91&amp;plusmn;0.17 ppb/year at KHMS for the period
      1991–2001) in comparison with later years
      (+0.04&amp;plusmn;0.21 ppb/year at JFJ and
      &amp;minus;0.37&amp;plusmn;0.14 ppb/year at KHMS for the period
      1997–2006). Trends show a distinct seasonality, which is different
      for the different periods. To investigate possible reasons for this
      remarkable trends difference 3-D trajectories using LAGRANTO trajectory
      model are used. Effects of the horizontal and vertical transport on
      ozone trends are considered. In general we could not find any
      systematic changes in the transport patterns which could explain the
      significant changes of the trends between 1991–2001 and 1997–2006. It
      is likely that the position of the main emission source areas relative
      to the stations is among the main reason for the opposite surface
      ozone trends. During the 1990s the JFJ trend
      reflects increase of the ozone in the upper free troposphere/lower
      stratosphere. In contrary KHSM is much more influenced by dramatic
      emission decrease in the earlier 1990s in former USSR and emissions
      regulations in Western Europe. For later years ozone trends at KHMS
      are controlled by slight emission increase in the region, while trends
      at JFJ correspond to the scenario of European emissions control.</p>
</abstract>
<counts><page-count count="50"/></counts>
</article-meta>
</front>
<body/>
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