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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-12-9985-2012</article-id>
<title-group>
<article-title>CO&lt;sub&gt;2&lt;/sub&gt; flux estimation errors associated with moist atmospheric processes</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Parazoo</surname>
<given-names>N. 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>Denning</surname>
<given-names>A. 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>Kawa</surname>
<given-names>S. R.</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>Pawson</surname>
<given-names>S.</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>Lokupitiya</surname>
<given-names>R.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USA</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>NASA Goddard Space Flight Center, Greenbelt, Maryland, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Department of Statistics and Computer Science, University of Sri Jawawardenepura, Gangodawila, Nugegoda, Sri Lanka</addr-line>
</aff>
<pub-date pub-type="epub">
<day>18</day>
<month>04</month>
<year>2012</year>
</pub-date>
<volume>12</volume>
<issue>4</issue>
<fpage>9985</fpage>
<lpage>10014</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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<abstract>
<p>Vertical transport by moist sub-grid scale processes such as deep convection
is a well-known source of uncertainty in CO&lt;sub&gt;2&lt;/sub&gt; source/sink inversion.
However, a dynamical link between moist transport, satellite CO&lt;sub&gt;2&lt;/sub&gt;
retrievals, and source/sink inversion has not yet been established. Here we
examine the effect of moist processes on (1) synoptic CO&lt;sub&gt;2&lt;/sub&gt; transport by
Version-4 and Version-5 NASA Goddard Earth Observing System Data
Assimilation System (NASA-DAS) meteorological analyses, and (2) source/sink
inversion. We find that synoptic transport processes, such as fronts and
dry/moist conveyors, feed off background vertical CO&lt;sub&gt;2&lt;/sub&gt; gradients, which
are modulated by sub-grid vertical transport. The implication for
source/sink estimation is two-fold. First, CO&lt;sub&gt;2&lt;/sub&gt; variations contained in
moist poleward moving air masses are systematically different from
variations in dry equatorward moving air. Moist poleward transport is hidden
from orbital sensors on satellites, causing a sampling bias, which leads
directly to continental scale source/sink estimation errors of up to 0.25 PgC yr&lt;sup&gt;−1&lt;/sup&gt;
in northern mid-latitudes. Second, moist processes are
represented differently in GEOS-4 and GEOS-5, leading to differences in
vertical CO&lt;sub&gt;2&lt;/sub&gt; gradients, moist poleward and dry equatorward CO&lt;sub&gt;2&lt;/sub&gt;
transport, and therefore the fraction of CO&lt;sub&gt;2&lt;/sub&gt; variations hidden in moist
air from satellites. As a result, sampling biases are amplified, causing
source/sink estimation errors of up to 0.55 PgC yr&lt;sup&gt;−1&lt;/sup&gt; in northern
mid-latitudes. These results, cast from the perspective of moist frontal
transport processes, support previous arguments that the vertical gradient
of CO&lt;sub&gt;2&lt;/sub&gt; is a major source of uncertainty in source/sink inversion.</p>
</abstract>
<counts><page-count count="30"/></counts>
</article-meta>
</front>
<body/>
<back>
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