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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-11-8543-2011</article-id>
<title-group>
<article-title>A high spatial resolution retrieval of NO&lt;sub&gt; 2&lt;/sub&gt; column densities from OMI: method and evaluation</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Russell</surname>
<given-names>A. R.</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>Perring</surname>
<given-names>A. E.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Valin</surname>
<given-names>L. 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>Bucsela</surname>
<given-names>E. J.</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>Browne</surname>
<given-names>E. 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>Wooldridge</surname>
<given-names>P. J.</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>Cohen</surname>
<given-names>R. C.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Chemistry, University of California Berkeley, Berkeley, CA, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>SRI International, Menlo Park, CA 94025, USA</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Department of Earth and Planetary Sciences, University of California Berkeley, Berkeley, CA, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>now at: Chemical Sciences Division, Earth Systems Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO, USA</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>now at: Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>22</day>
<month>08</month>
<year>2011</year>
</pub-date>
<volume>11</volume>
<issue>16</issue>
<fpage>8543</fpage>
<lpage>8554</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/11/8543/2011/acp-11-8543-2011.html">This article is available from http://www.atmos-chem-phys.net/11/8543/2011/acp-11-8543-2011.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/11/8543/2011/acp-11-8543-2011.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/8543/2011/acp-11-8543-2011.pdf</self-uri>
<abstract>
<p>We present a new retrieval of tropospheric NO&lt;sub&gt;2&lt;/sub&gt; vertical column density
from the Ozone Monitoring Instrument (OMI) based on high spatial and
temporal resolution terrain and profile inputs. We compare our NO&lt;sub&gt;2&lt;/sub&gt;
product, the Berkeley High-Resolution (BEHR) product, with operational
retrievals and find that the operational retrievals are biased high (30 %)
over remote areas and biased low (8 %) over urban regions. Additionally,
we find non-negligible impacts on the retrieved NO&lt;sub&gt;2&lt;/sub&gt; column for terrain
pressure (±20 %), albedo (±40 %), and NO&lt;sub&gt;2&lt;/sub&gt; vertical
profile (−75 %–+10 %). We validate the operational and BEHR products
using boundary layer aircraft observations from the Arctic Research of the
Composition of the Troposphere from Aircraft and Satellites (ARCTAS-CA)
field campaign which occurred in June 2008 in California. Results indicate
that columns derived using our boundary layer extrapolation method show good
agreement with satellite observations (&lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; = 0.65–0.83; &lt;i&gt;N&lt;/i&gt; = 68) and
provide a more robust validation of satellite-observed NO&lt;sub&gt;2&lt;/sub&gt; column than
those determined using full vertical spirals (&lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; = 0.26; &lt;i&gt;N&lt;/i&gt; = 5) as in
previous work. Agreement between aircraft observations and the BEHR product
(&lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; = 0.83) is better than agreement with the operational products
(&lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; = 0.65–0.72). We also show that agreement between satellite and
aircraft observations can be further improved (e.g. BEHR: &lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; = 0.91)
using cloud information from the Moderate Resolution Imaging
Spectroradiometer (MODIS) instrument instead of the OMI cloud product. These
results indicate that much of the variance in the operational products can
be attributed to coarse resolution terrain pressure, albedo, and profile
parameters implemented in the retrievals.</p>
</abstract>
<counts><page-count count="12"/></counts>
</article-meta>
</front>
<body/>
<back>
<ref-list>
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