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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-10-453-2010</article-id>
<title-group>
<article-title>Increasing synoptic scale variability in atmospheric CO&lt;sub&gt;2&lt;/sub&gt; at Hateruma Island associated with increasing East-Asian emissions</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Tohjima</surname>
<given-names>Y.</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>Mukai</surname>
<given-names>H.</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>Hashimoto</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>Patra</surname>
<given-names>P. K.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Atmospheric Environment Division, National Institute for Environmental Studies, Tsukuba, Japan</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Research Institute for Global Change, JAMSTEC, Yokohama, Japan</addr-line>
</aff>
<pub-date pub-type="epub">
<day>19</day>
<month>01</month>
<year>2010</year>
</pub-date>
<volume>10</volume>
<issue>2</issue>
<fpage>453</fpage>
<lpage>462</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.net/10/453/2010/acp-10-453-2010.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/453/2010/acp-10-453-2010.pdf</self-uri>
<abstract>
<p>In-situ observations of atmospheric CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;4&lt;/sub&gt; at
Hateruma Island (24.05&amp;deg; N, 123.80&amp;deg; E, 47 m a.s.l),
Japan shows large synoptic scale variations during a 6-month period
from November to April, when the sampled air is predominantly of
continental origin due to the Asian winter monsoon. Synoptic scale
variations are extracted from the daily averaged values for the
years between 1996 and 2007, along with the annual standard
deviations (&amp;sigma;&lt;sub&gt;CO&lt;/sub&gt;&lt;sub&gt;2&lt;/sub&gt; and &amp;sigma;&lt;sub&gt;CH&lt;/sub&gt;&lt;sub&gt;4&lt;/sub&gt; for
CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;4&lt;/sub&gt;, respectively) for the relevant 6-month
period. During this 6-month period the absolute mixing ratios of
CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;4&lt;/sub&gt; at Hateruma are also elevated compared to
those at two sites in the central North Pacific Ocean. The temporal
change in &amp;sigma;&lt;sub&gt;CO&lt;/sub&gt;&lt;sub&gt;2&lt;/sub&gt; shows a systematic increase over the
12-year period, with elevated excursions in 1998 and 2003; there is
no clear increase in &amp;sigma;&lt;sub&gt;CH&lt;/sub&gt;&lt;sub&gt;4&lt;/sub&gt;. We also find that the
&amp;sigma;&lt;sub&gt;CO&lt;/sub&gt;&lt;sub&gt;2&lt;/sub&gt;/&amp;sigma;&lt;sub&gt;CH&lt;/sub&gt;&lt;sub&gt;4&lt;/sub&gt; ratio increases gradually
from 1996 to 2002 and rapidly after 2002 without any extreme
deviations that characterised &amp;sigma;&lt;sub&gt;CO&lt;/sub&gt;&lt;sub&gt;2&lt;/sub&gt;. The &amp;sigma;&lt;sub&gt;CO&lt;/sub&gt;&lt;sub&gt;2&lt;/sub&gt;/&amp;sigma;&lt;sub&gt;CH&lt;/sub&gt;&lt;sub&gt;4&lt;/sub&gt; ratio correlates closely with the recent
rapid increase in fossil carbon emissions from China, as indicated
in the Carbon Dioxide Information Analysis Center (CDIAC) database.
This methodology can be applied to multiple chemical tracers of
sufficient lifetime, for tracking overall changes in regional
emissions.</p>
</abstract>
<counts><page-count count="10"/></counts>
</article-meta>
</front>
<body/>
<back>
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