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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>
<abbrev-journal-title abbrev-type="nlm-ta">Atmos. Chem. Phys.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7324</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>GÃ¶ttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-11-7465-2011</article-id>
<title-group>
<article-title>Spatial variation of chemical composition and sources of submicron aerosol in Zurich during wintertime using mobile aerosol mass spectrometer data</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Mohr</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>Richter</surname>
<given-names>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>DeCarlo</surname>
<given-names>P. F.</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>PrÃ©vÃ´t</surname>
<given-names>A. S. 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>Baltensperger</surname>
<given-names>U.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Laboratory of Atmospheric Chemistry, Paul Scherrer Institut (PSI), Villigen, Switzerland</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>now at: AAAS Science and Technology Policy Fellow hosted at the US EPA, Washington 7 DC, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>01</day>
<month>08</month>
<year>2011</year>
</pub-date>
<volume>11</volume>
<issue>15</issue>
<fpage>7465</fpage>
<lpage>7482</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2011 C. Mohr et al.</copyright-statement>
<copyright-year>2011</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://acp.copernicus.org/articles/11/7465/2011/acp-11-7465-2011.html">This article is available from https://acp.copernicus.org/articles/11/7465/2011/acp-11-7465-2011.html</self-uri>
<self-uri xlink:href="https://acp.copernicus.org/articles/11/7465/2011/acp-11-7465-2011.pdf">The full text article is available as a PDF file from https://acp.copernicus.org/articles/11/7465/2011/acp-11-7465-2011.pdf</self-uri>
<abstract>
<p>Mobile measurements of PM&lt;sub&gt;1&lt;/sub&gt; (particulate matter with an aerodynamic
diameter &lt;1 Î¼m) chemical composition using a quadrupole aerosol mass
spectrometer and a multi-angle absorption photometer were performed using
the PSI mobile laboratory during winter 2007/2008 and December 2008 in the
metropolitan area of Zurich, Switzerland. Positive matrix factorization
(PMF) applied to the organic fraction of PM&lt;sub&gt;1&lt;/sub&gt; yielded 3 factors:
Hydrocarbon-like organic aerosol (HOA) related to traffic emissions; organic
aerosol from wood burning for domestic heating purposes (WBOA); and
oxygenated organic aerosol (OOA), assigned to secondary organic aerosol
formed by oxidation of volatile precursors. The chemical composition of
PM&lt;sub&gt;1&lt;/sub&gt; was assessed for an urban background site and various sites
throughout the city. The background site is dominated by secondary inorganic
and organic species (57 %), BC, HOA, and WBOA account for 15 %, 6 %,
and 12 %, respectively. As for the other sites, HOA is important along
major roads (varying between 7 and 14 % of PM&lt;sub&gt;1&lt;/sub&gt; for different sites
within the city, average all sites 8 %), domestic wood burning makes up
between 8â€“15 % of PM&lt;sub&gt;1&lt;/sub&gt; for different sites within the city (average
all sites 10.5 %). OOA makes up the largest fraction of organic aerosol
(44 % on average). A new method allows for the separation and
quantification of the local fraction of PM&lt;sub&gt;1&lt;/sub&gt; emitted or rapidly formed
in the city, and the fraction of PM&lt;sub&gt;1&lt;/sub&gt; originating from the urban
background. The method is based on simultaneous on-road mobile and
stationary background measurements and the correction of small-scale
meteorological effects using the ratio of on-road sulfate to stationary
sulfate. Especially during thermal inversions over the Swiss plateau, urban
background concentrations contribute substantially to particulate number
concentrations (between 40 and 80 % depending on meteorological conditions
and emissions, 60 % on average) as well as to the mass concentrations of
PM&lt;sub&gt;1&lt;/sub&gt; components measured on road in downtown Zurich (between 30 and
90 %, on average 60 % for black carbon and HOA, and between 90 and
100 % for WBOA, OOA, and the measured inorganic components). The results
emphasize, on a scientific level, the advantage of mobile measurements for
distinguishing local from regional air pollution research, and on a
political level, the importance of regional collaboration for mitigating air
pollution issues.</p>
</abstract>
<counts><page-count count="18"/></counts>
</article-meta>
</front>
<body/>
<back>
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