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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-10-1671-2010</article-id>
<title-group>
<article-title>Source-receptor relationships for airborne measurements of CO&lt;sub&gt;2&lt;/sub&gt;, CO and O&lt;sub&gt;3&lt;/sub&gt; above Siberia: a cluster-based approach</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Paris</surname>
<given-names>J.-D.</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>Stohl</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>Ciais</surname>
<given-names>P.</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>NÃ©dÃ©lec</surname>
<given-names>P.</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>Belan</surname>
<given-names>B. D.</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>Arshinov</surname>
<given-names>M. Yu.</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>Ramonet</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Laboratoire des Sciences du Climat et de l&apos;Environnement/IPSL, CEA-CNRS-UVSQ, UMR1572, Gif sur Yvette, France</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Norwegian Institute for Air Research (NILU), Kjeller, Norway</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Laboratoire d&apos;AÃ©rologie, Observatoire Midi PyrÃ©nÃ©es, CNRS-UPS, Toulouse, France</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Zuev Institute of Atmospherics Optics, SB RAS, Tomsk, Russia</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>1671</fpage>
<lpage>1687</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/10/1671/2010/acp-10-1671-2010.html">This article is available from http://www.atmos-chem-phys.net/10/1671/2010/acp-10-1671-2010.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/10/1671/2010/acp-10-1671-2010.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/1671/2010/acp-10-1671-2010.pdf</self-uri>
<abstract>
<p>We analysed results of three intensive aircraft campaigns above Siberia
(April and September 2006, August 2007) with a total of ~70 h of
continuous CO&lt;sub&gt;2&lt;/sub&gt;, CO and O&lt;sub&gt;3&lt;/sub&gt; measurements. The flight route consists
of consecutive ascents and descents between Novosibirsk (55&amp;deg; N, 82&amp;deg; E)
and Yakutsk (62&amp;deg; N, 129&amp;deg; E). We performed retroplume calculations with
the Lagrangian particle dispersion model FLEXPART for many short segments
along the flight tracks. To reduce the extremely rich information on source
regions provided by the model calculation into a small number of distinct
cases, we performed a statistical clustering â€“ to our knowledge for the
first time â€“ into potential source regions of the footprint emission
sensitivities obtained from the model calculations. This technique not only
worked well to separate source region influences but also resulted in
clearly distinct tracer concentrations for the various clusters obtained.
High CO and O&lt;sub&gt;3&lt;/sub&gt; concentrations were found associated with agricultural
fire plumes originating from Kazakhstan in September 2006. A statistical
analysis indicates that summer uptake of CO&lt;sub&gt;2&lt;/sub&gt; is largely explained
(~50% of variance) by air mass exposure to uptake by Siberian and
sub-arctic ecosystems. This resulted in an average 5 to 10 ppm difference
with overlaying air masses. Stratosphere-troposphere exchange is found to
strongly influence the observed O&lt;sub&gt;3&lt;/sub&gt; mixing ratios in spring, but not in
summer. European emissions contributed to high O&lt;sub&gt;3&lt;/sub&gt; concentrations above
Siberia in April 2006 and August 2007, while emissions from North Eastern
China also contributed to higher O&lt;sub&gt;3&lt;/sub&gt; mixing ratios in summer, but tend
to lower mixing ratios in spring, when the airmass aerosol burden is
important. In the lower troposphere, large-scale deposition processes in the
boreal and sub-arctic boundary layer is a large O&lt;sub&gt;3&lt;/sub&gt; sink, resulting in a
~20 ppb difference with overlaying air masses. Lagrangian footprint
clustering is very promising and could also be advantageously applied to the
interpretation of ground based measurements including calculation of
tracers&apos; sources and sinks.</p>
</abstract>
<counts><page-count count="17"/></counts>
</article-meta>
</front>
<body/>
<back>
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