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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-7-557-2007</article-id>
<title-group>
<article-title>Ozone production and hydrocarbon reactivity in Hong Kong, Southern China</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zhang</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wang</surname>
<given-names>T.</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>Chameides</surname>
<given-names>W. L.</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>Cardelino</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>Kwok</surname>
<given-names>J.</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>Blake</surname>
<given-names>D. R.</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>Ding</surname>
<given-names>A.</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>So</surname>
<given-names>K. L.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>School of Geography, Beijing Normal University, Beijing 100875, China</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Department of Chemistry, University of California, Irvine, CA 92697, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>30</day>
<month>01</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>2</issue>
<fpage>557</fpage>
<lpage>573</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/7/557/2007/acp-7-557-2007.html">This article is available from http://www.atmos-chem-phys.net/7/557/2007/acp-7-557-2007.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/557/2007/acp-7-557-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/557/2007/acp-7-557-2007.pdf</self-uri>
<abstract>
<p>Data obtained in Hong Kong during the Hong Kong and the Pearl River Delta
(PRD) Pilot Air Monitoring Study in autumn 2002 are analyzed to unravel the
relationship between ground-level ozone (O&lt;sub&gt;3&lt;/sub&gt;), pollution precursors, and
cross-border transport. Ten ozone episodes, during which the hourly O&lt;sub&gt;3&lt;/sub&gt;
concentration exceeded 100 ppbv in 9 cases and 90 ppbv in one case, are
subject to detailed analysis, including one case with hourly O&lt;sub&gt;3&lt;/sub&gt; of 203 ppbv,
which is the highest concentration on record to date in Hong Kong.
Combined with high-resolution back trajectories, dCO/dNO&lt;sub&gt;y&lt;/sub&gt; (the ratio of
enhancement of CO concentration above background to that of NO&lt;sub&gt;y&lt;/sub&gt;) is
used to define whether O&lt;sub&gt;3&lt;/sub&gt; is locally or regionally produced. Five out
of the ten Hong Kong O&lt;sub&gt;3&lt;/sub&gt;-episodes studied show a &quot;pollution signature&quot;
that is indicative of impact from Guangdong Province. Examination of
speciated volatile organic compounds (VOCs) shows that the reactivity of
VOCs is dominated by anthropogenic VOCs, of which the reactive aromatics
dominate, in particular xylenes and toluene. Calculations using a
photochemical box model indicate that between 50&amp;ndash;100% of the O&lt;sub&gt;3&lt;/sub&gt;
increase observed in Hong Kong during the O&lt;sub&gt;3&lt;/sub&gt; episodes can be explained
by photochemical generation within the Hong Kong area, provided that nitrous
acid (HONO) is present at the concentrations derived from this study. An
Observation-Based Model (OBM) is used to calculate the sensitivity of the
O&lt;sub&gt;3&lt;/sub&gt; production to changes in the concentrations of the precursor
compounds. Generally the production of O&lt;sub&gt;3&lt;/sub&gt; throughout much of the Hong
Kong area is limited by VOCs, while high nitric oxide (NO) concentrations
suppress O&lt;sub&gt;3&lt;/sub&gt; concentration.</p>
</abstract>
<counts><page-count count="17"/></counts>
</article-meta>
</front>
<body/>
<back>
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