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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-7-329-2007</article-id>
<title-group>
<article-title>Distribution, magnitudes, reactivities, ratios and diurnal patterns of volatile organic compounds in the Valley of Mexico during the MCMA 2002 &amp; 2003 field campaigns</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Velasco</surname>
<given-names>E.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lamb</surname>
<given-names>B.</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>Westberg</surname>
<given-names>H.</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>Allwine</surname>
<given-names>E.</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>Sosa</surname>
<given-names>G.</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>Arriaga-Colina</surname>
<given-names>J. L.</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>Jobson</surname>
<given-names>B. T.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<xref ref-type="aff" rid="aff10">
<sup>10</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Alexander</surname>
<given-names>M. L.</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>Prazeller</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>Knighton</surname>
<given-names>W. B.</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>Rogers</surname>
<given-names>T. M.</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>Grutter</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Herndon</surname>
<given-names>S. C.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kolb</surname>
<given-names>C. E.</given-names>
</name>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Zavala</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>de Foy</surname>
<given-names>B.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Volkamer</surname>
<given-names>R.</given-names>
</name>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Molina</surname>
<given-names>L. T.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Molina</surname>
<given-names>M. J.</given-names>
</name>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Laboratory for Atmospheric Research, Department of Civil and Environmental Engineering, Washington State University, Pullman WA, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Laboratorio de Química de la Atmósfera, Instituto Mexicano del Petróleo, México D.F., México</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Atmospheric Sciences. Battelle Pacific Northwest National Laboratory, Richland WA, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Department of Chemistry and Biochemistry, Montana State University, Bozeman MO, USA</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, México D.F., México</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Center for Atmospheric and Environmental Chemistry, Aerodyne Research Inc., Billerica, MA, USA</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge MA, USA</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>Department of Chemistry and Biochemistry, University of California, San Diego, USA</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>now at: Molina Center for Energy and the Environment (mce2.org), La Jolla CA, USA</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>now at: Washington State University, Pullman WA, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>23</day>
<month>01</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>2</issue>
<fpage>329</fpage>
<lpage>353</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/7/329/2007/acp-7-329-2007.html">This article is available from http://www.atmos-chem-phys.net/7/329/2007/acp-7-329-2007.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/329/2007/acp-7-329-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/329/2007/acp-7-329-2007.pdf</self-uri>
<abstract>
<p>A wide array of volatile organic compound (VOC) measurements was conducted
in the Valley of Mexico during the MCMA-2002 and 2003 field campaigns. Study
sites included locations in the urban core, in a heavily industrial area and
at boundary sites in rural landscapes. In addition, a novel
mobile-laboratory-based conditional sampling method was used to collect
samples dominated by fresh on-road vehicle exhaust to identify those VOCs
whose ambient concentrations were primarily due to vehicle emissions. Four
distinct analytical techniques were used: whole air canister samples with
Gas Chromatography/Flame Ionization Detection (GC-FID), on-line chemical
ionization using a Proton Transfer Reaction Mass Spectrometer (PTR-MS),
continuous real-time detection of olefins using a Fast Olefin Sensor (FOS),
and long path measurements using UV Differential Optical Absorption
Spectrometers (DOAS). The simultaneous use of these techniques provided a
wide range of individual VOC measurements with different spatial and
temporal scales. The VOC data were analyzed to understand concentration and
spatial distributions, diurnal patterns, origin and reactivity in the
atmosphere of Mexico City. The VOC burden (in ppbC) was dominated by alkanes
(60%), followed by aromatics (15%) and olefins (5%). The remaining
20% was a mix of alkynes, halogenated hydrocarbons, oxygenated species
(esters, ethers, etc.) and other unidentified VOCs. However, in terms of
ozone production, olefins were the most relevant hydrocarbons. Elevated
levels of toxic hydrocarbons, such as 1,3-butadiene, benzene, toluene and
xylenes, were also observed. Results from these various analytical
techniques showed that vehicle exhaust is the main source of VOCs in Mexico
City and that diurnal patterns depend on vehicular traffic in addition to
meteorological processes. Finally, examination of the VOC data in terms of
lumped modeling VOC classes and its comparison to the VOC lumped emissions
reported in other photochemical air quality modeling studies suggests that
some alkanes are underestimated in the emissions inventory, while some
olefins and aromatics are overestimated.</p>
</abstract>
<counts><page-count count="25"/></counts>
</article-meta>
</front>
<body/>
<back>
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