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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-10-12295-2010</article-id>
<title-group>
<article-title>Ozone, carbon monoxide and nitrogen oxides time series at four alpine GAW mountain stations in central Europe</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Gilge</surname>
<given-names>S.</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>Plass-Duelmer</surname>
<given-names>C.</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>Fricke</surname>
<given-names>W.</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>Kaiser</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>Ries</surname>
<given-names>L.</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>Buchmann</surname>
<given-names>B.</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>Steinbacher</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Hohenpeissenberg Meteorological Observatory, German Meteorological Service (DWD), Hohenpeissenberg, Germany</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Central Institute for Meteorology and Geodynamics (ZAMG), Vienna, Austria</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Federal Environment Agency (UBA), Zugspitze, Germany</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Swiss Federal Laboratories for Materials Science and Technology (EMPA), Duebendorf, Switzerland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>23</day>
<month>12</month>
<year>2010</year>
</pub-date>
<volume>10</volume>
<issue>24</issue>
<fpage>12295</fpage>
<lpage>12316</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/10/12295/2010/acp-10-12295-2010.html">This article is available from http://www.atmos-chem-phys.net/10/12295/2010/acp-10-12295-2010.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/10/12295/2010/acp-10-12295-2010.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/12295/2010/acp-10-12295-2010.pdf</self-uri>
<abstract>
<p>Long-term, ground based in-situ observations of ozone (O&lt;sub&gt;3&lt;/sub&gt;) and its
precursor gases nitrogen dioxide (NO&lt;sub&gt;2&lt;/sub&gt;) and carbon monoxide (CO) from
the four sites Hohenpeissenberg and Zugspitze (D), Sonnblick (A) and
Jungfraujoch (CH) are presented for the period 1995–2007. These Central
European alpine mountain observatories cover an altitude range of roughly
1000 to 3500 m. Comparable analytical methods and common quality assurance
(QA) procedures are used at all sites. For O&lt;sub&gt;3&lt;/sub&gt; and CO, calibration is
linked to primary calibrations (O&lt;sub&gt;3&lt;/sub&gt;) or CO standards provided by the
Central Calibration Laboratory (CCL) at NOAA/ESRL. All stations have been
audited by the World Calibration Centre (WCC) for CO and O&lt;sub&gt;3&lt;/sub&gt; (WCC-Empa;
CH). Data from long-term measurements of NO&lt;sub&gt;2&lt;/sub&gt; and CO are only available
from Hohenpeissenberg and Jungfraujoch. Both sites show slightly decreasing
mixing ratios of the primarily emitted NO&lt;sub&gt;2&lt;/sub&gt; and the partly
anthropogenically emitted CO between 1995 and 2007. The findings are
generally consistent with shorter observation periods at Zugspitze and
Sonnblick and thus are considered to represent regional changes in Central
European atmospheric composition at this altitude range. Over the same
period, 1995–2007, the O&lt;sub&gt;3&lt;/sub&gt; mixing ratios have slightly increased at three
of the four sites independent of wind sector. Trends are often more
pronounced in winter and less in summer; highest declines of NO&lt;sub&gt;2&lt;/sub&gt; and CO
are observed in winter and the lowest in summer, whereas the strongest
O&lt;sub&gt;3&lt;/sub&gt; increase was detected in winter and lowest or even decline in
summer, respectively. Weekly cycles demonstrate anthropogenic impact at all
elevations with enhanced NO&lt;sub&gt;2&lt;/sub&gt; on working days compared to weekends.
Enhanced O&lt;sub&gt;3&lt;/sub&gt; values on working days indicating photochemical production
from anthropogenic precursors are only observed in summer, whereas in all
other seasons anti-correlation with NO&lt;sub&gt;2&lt;/sub&gt; was found due to reduced
O&lt;sub&gt;3&lt;/sub&gt; values on working days. Trends are discussed with respect to
anthropogenic impacts and vertical mixing. The observed trends for NO&lt;sub&gt;2&lt;/sub&gt;
at the alpine mountain sites are less pronounced than trends estimated based
on emission inventories.</p>
</abstract>
<counts><page-count count="22"/></counts>
</article-meta>
</front>
<body/>
<back>
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