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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-10-1599-2010</article-id>
<title-group>
<article-title>Atmospheric oxygen and carbon dioxide observations from two European coastal stations 2000–2005: continental influence, trend changes and APO climatology</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Sirignano</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>Neubert</surname>
<given-names>R. E. M.</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>Rödenbeck</surname>
<given-names>C.</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>Meijer</surname>
<given-names>H. A. J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Centre for Isotope Research, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Max-Planck-Institute for Biogeochemistry, Hans-Knoell-Straße 10, 07745 Jena, Germany</addr-line>
</aff>
<pub-date pub-type="epub">
<day>15</day>
<month>02</month>
<year>2010</year>
</pub-date>
<volume>10</volume>
<issue>4</issue>
<fpage>1599</fpage>
<lpage>1615</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/10/1599/2010/acp-10-1599-2010.html">This article is available from http://www.atmos-chem-phys.net/10/1599/2010/acp-10-1599-2010.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/10/1599/2010/acp-10-1599-2010.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/1599/2010/acp-10-1599-2010.pdf</self-uri>
<abstract>
<p>Seeking for baseline conditions has biased the atmospheric carbon dioxide
(CO&lt;sub&gt;2&lt;/sub&gt;) and later on also oxygen (O&lt;sub&gt;2&lt;/sub&gt;) monitoring networks towards
remote marine stations, missing part of the variability that is due to
regional anthropogenic as well as land biotic activity. We present here a
five-year record of atmospheric CO&lt;sub&gt;2&lt;/sub&gt; concentrations and oxygen/nitrogen
(O&lt;sub&gt;2&lt;/sub&gt;/N&lt;sub&gt;2&lt;/sub&gt;) ratio measurements from the coastal stations Lutjewad
(LUT), The Netherlands and Mace Head (MHD), Ireland, derived from flask
samples. O&lt;sub&gt;2&lt;/sub&gt;/N&lt;sub&gt;2&lt;/sub&gt; ratios, a proxy for O&lt;sub&gt;2&lt;/sub&gt; concentrations,
concurrently measured with CO&lt;sub&gt;2&lt;/sub&gt; concentrations, help determine
regional CO&lt;sub&gt;2&lt;/sub&gt; fluxes by separating land fluxes from sea fluxes. Mace
Head is the closest marine baseline station to Lutjewad, located at the same
latitude, and therefore is taken as a reference. During the studied period,
from 2000 until 2005, we observed an average increase of CO&lt;sub&gt;2&lt;/sub&gt; in the
atmosphere of (1.7&amp;plusmn;0.2) ppm y&lt;sup&gt;&amp;minus;1&lt;/sup&gt;, and a change of the
O&lt;sub&gt;2&lt;/sub&gt;/N&lt;sub&gt;2&lt;/sub&gt; ratio of (&amp;minus;20&amp;plusmn;1) per meg y&lt;sup&gt;&amp;minus;1&lt;/sup&gt;. The difference
between the CO&lt;sub&gt;2&lt;/sub&gt; summer minimum and the winter maximum is 14.4 ppm and
16.1 ppm at Mace Head and Lutjewad, respectively, while the paraphase
variation in the O&lt;sub&gt;2&lt;/sub&gt; signal equals 113 per meg and 153 per meg,
respectively. We also studied the atmospheric potential oxygen (APO) tracer
at both stations. By this analysis, evidence has been found that we need to
be careful when using APO close to anthropogenic CO&lt;sub&gt;2&lt;/sub&gt; sources. It could
be biased by combustion-derived CO&lt;sub&gt;2&lt;/sub&gt;, and models need to take into
account daily and seasonal variations in the anthropogenic CO&lt;sub&gt;2&lt;/sub&gt;
production in order to be able to simulate APO over the continents.</p>
</abstract>
<counts><page-count count="17"/></counts>
</article-meta>
</front>
<body/>
<back>
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