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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>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-13-10933-2013</article-id>
<title-group>
<article-title>In situ submicron organic aerosol characterization at a boreal forest research station during HUMPPA-COPEC 2010 using soft and hard ionization mass spectrometry</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Vogel</surname>
<given-names>A. L.</given-names>
<ext-link>https://orcid.org/0000-0002-1293-6370</ext-link>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Äijälä</surname>
<given-names>M.</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>Corrigan</surname>
<given-names>A. 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>Junninen</surname>
<given-names>H.</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>Ehn</surname>
<given-names>M.</given-names>
<ext-link>https://orcid.org/0000-0002-0215-4893</ext-link>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Petäjä</surname>
<given-names>T.</given-names>
<ext-link>https://orcid.org/0000-0002-1881-9044</ext-link>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Worsnop</surname>
<given-names>D. R.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</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>Kulmala</surname>
<given-names>M.</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>Russell</surname>
<given-names>L. M.</given-names>
<ext-link>https://orcid.org/0000-0002-6108-2375</ext-link>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Williams</surname>
<given-names>J.</given-names>
<ext-link>https://orcid.org/0000-0001-9421-1703</ext-link>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hoffmann</surname>
<given-names>T.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg-University Mainz, 55128 Mainz, Germany</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Physics, University of Helsinki, 00014 Helsinki, Finland</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Scripps Institution of Oceanography and the University of California, San Diego, La Jolla, CA 92093, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, 55128 Mainz, Germany</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Aerodyne Research Inc, Billerica, MA 01821, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>08</day>
<month>11</month>
<year>2013</year>
</pub-date>
<volume>13</volume>
<issue>21</issue>
<fpage>10933</fpage>
<lpage>10950</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2013 A. L. Vogel et al.</copyright-statement>
<copyright-year>2013</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/13/10933/2013/acp-13-10933-2013.html">This article is available from https://acp.copernicus.org/articles/13/10933/2013/acp-13-10933-2013.html</self-uri>
<self-uri xlink:href="https://acp.copernicus.org/articles/13/10933/2013/acp-13-10933-2013.pdf">The full text article is available as a PDF file from https://acp.copernicus.org/articles/13/10933/2013/acp-13-10933-2013.pdf</self-uri>
<abstract>
<p>The chemical composition of submicron aerosol during the comprehensive field
campaign HUMPPA-COPEC 2010 at Hyytiälä, Finland, is presented. The
focus lies on online measurements of organic acids, which were achieved by
using atmospheric pressure chemical ionization (APCI) ion trap mass
spectrometry (IT-MS). These measurements were accompanied by aerosol mass
spectrometry (AMS) measurements and Fourier transform infrared spectroscopy
(FTIR) of filter samples, all showing a high degree of correlation. The soft
ionization mass spectrometer alternated between gas-phase measurements
solely and measuring the sum of gas and particle phase.
&lt;br&gt;&lt;br&gt;
The AMS measurements of C, H and O elemental composition show that the
aerosol during the campaign was highly oxidized, which appears reasonable
due to high and prolonged radiation during the boreal summer measurement
period as well as the long transport times of some of the aerosol. In order
to contrast ambient and laboratory aerosol, an average organic acid pattern,
measured by APCI-IT-MS during the campaign, was compared to terpene
ozonolysis products in a laboratory reaction chamber. Identification of
single organic acid species remains a major challenge due to the complexity
of the boreal forest aerosol. Unambiguous online species identification was
attempted by the combinatorial approach of identifying unique fragments in
the MS&lt;sup&gt;2&lt;/sup&gt; mode of standards, and then comparing these results with
MS&lt;sup&gt;2&lt;/sup&gt; field spectra. During the campaign, unique fragments of
limonene-derived organic acids (limonic acid and ketolimononic acid) and of the
biomass burning tracer vanillic acid were detected. Other specific fragments
(neutral loss of 28 Da) in the MS&lt;sup&gt;2&lt;/sup&gt; suggest the occurrence of
semialdehydes.
&lt;br&gt;&lt;br&gt;
Furthermore, an approach to determine the average molecular weight of the
aerosol is presented. The campaign average organic molecular weight was
determined to be 300 g mol&lt;sup&gt;−1&lt;/sup&gt;. However, a plume of aged biomass burning
aerosol, arriving at Hyytiälä from Russia, contained organic
compounds up to 800 Da (&lt;span style=&quot;border-top: 1px solid #000; color: #000;&quot;&gt;MW&lt;/span&gt;&lt;sub&gt;om&lt;/sub&gt;&amp;approx;450 g mol&lt;sup&gt;−1&lt;/sup&gt;), showing that the average molecular weight can vary
significantly. The high measurement frequency of both AMS and APCI-IT-MS
enabled the partitioning of selected organic acids between gas and
particle phase as a function of the total particulate mass to be quantified.
Surprisingly high fractions of the higher molecular weight organic acids were
observed to reside in the gas phase. These observations might be a
consequence of large equilibration timescales for semi-solid boreal forest
aerosol, as has been recently hypothesized by Shiraiwa and Seinfeld
(2012).</p>
</abstract>
<counts><page-count count="18"/></counts>
</article-meta>
</front>
<body/>
<back>
<ref-list>
<title>References</title>
<ref id="ref1">
<label>1</label><mixed-citation publication-type="other" xlink:type="simple">Alfarra, M. R., Hamilton, J. F., Wyche, K. P., Good, N., Ward, M. W., Carr, T., Barley, M. H., Monks, P. S., Jenkin, M. E., Lewis, A. C., and McFiggans, G. B.: The effect of photochemical ageing and initial precursor concentration on the composition and hygroscopic properties of β-caryophyllene secondary organic aerosol, Atmos. Chem. Phys., 12, 6417–6436, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-12-6417-2012&quot;&gt;https://doi.org/10.5194/acp-12-6417-2012&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple">Allan J., Jimenez J., Williams P., Alfarra M., Bower K., Jayne J., Coe H., and Worsnop D. R.: Quantitative sampling using an Aerodyne aerosol mass spectrometer: 1. Techniques of data interpretation and error analysis, J. Geophys. Res.-Atmos., 108, 4090, &lt;a href=&quot;http://dx.doi.org/10.1029/2002JD002358&quot;&gt;https://doi.org/10.1029/2002JD002358&lt;/a&gt;, 2003.</mixed-citation>
</ref>
<ref id="ref3">
<label>3</label><mixed-citation publication-type="other" xlink:type="simple">Allan J., Delia A., Coe H., Bower K., Alfarra M.R., Jimenez J., Middlebrook A., Drewnick F., Onasch T., Canagaratna M., Jayne J., and Worsnop D. R.: A generalised method for the extraction of chemically resolved mass spectra from Aerodyne aerosol mass spectrometer data, J. Aerosol Sci., 35, 909–922, 2004.</mixed-citation>
</ref>
<ref id="ref4">
<label>4</label><mixed-citation publication-type="other" xlink:type="simple">Andreae, M. O. and Merlet, P.: Emission of trace gases and aerosols from biomass burning, Global Biochem. Cy., 15, 955–966, &lt;a href=&quot;http://dx.doi.org/10.1029/2000GB001382&quot;&gt;https://doi.org/10.1029/2000GB001382&lt;/a&gt;, 2001.</mixed-citation>
</ref>
<ref id="ref5">
<label>5</label><mixed-citation publication-type="other" xlink:type="simple">Aufmhoff, H., Hanke, M., Uecker, J., Schlager, H., and Arnold, F.: An ion trap CIMS instrument for combined measurements of atmospheric OH and H2SO4: First test measurements above and inside the planetary boundary layer, Int. J. Mass Spectrom., 308, 26–34, &lt;a href=&quot;http://dx.doi.org/10.1016/j.ijms.2011.07.016&quot;&gt;https://doi.org/10.1016/j.ijms.2011.07.016&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref6">
<label>6</label><mixed-citation publication-type="other" xlink:type="simple">Bartmess, J. E.: Gas-Phase Equilibrium Affinity Scales and Chemical Ionization Mass-Spectrometry, Mass Spectrom. Rev., 8, 297–343, &lt;a href=&quot;http://dx.doi.org/10.1002/mas.1280080502&quot;&gt;https://doi.org/10.1002/mas.1280080502&lt;/a&gt;, 1989.</mixed-citation>
</ref>
<ref id="ref7">
<label>7</label><mixed-citation publication-type="other" xlink:type="simple">Bonan, G. B.: Forests and climate change: Forcings, feedbacks, and the climate benefits of forests, Science, 320, 1444–1449, &lt;a href=&quot;http://dx.doi.org/10.1126/science.1155121&quot;&gt;https://doi.org/10.1126/science.1155121&lt;/a&gt;, 2008.</mixed-citation>
</ref>
<ref id="ref8">
<label>8</label><mixed-citation publication-type="other" xlink:type="simple">Caldwell, G., Renneboog, R., and Kebarle, P.: Gas phase acidities of aliphatic carboxylic acids, based on measurements of proton transfer equilibria, Canadian Journal of Chemistry-Revue Canadienne De Chimie, 67, 611–618, &lt;a href=&quot;http://dx.doi.org/10.1139/v89-092&quot;&gt;https://doi.org/10.1139/v89-092&lt;/a&gt;, 1989.</mixed-citation>
</ref>
<ref id="ref9">
<label>9</label><mixed-citation publication-type="other" xlink:type="simple">Canagaratna, M. R., Jayne, J. T., Jimenez, J. L., Allan, J. D., Alfarra, M. R., Zhang, Q., Onasch, T. B., Drewnick, F., Coe, H., Middlebrook, A., Delia, A., Williams, L. R., Trimborn, A. M., Northway, M. J., DeCarlo, P. F., Kolb, C. E., Davidovits, P., and Worsnop, D. R.: Chemical and microphysical characterization of ambient aerosols with the aerodyne aerosol mass spectrometer, Mass Spectrom. Rev., 26, 185–222, &lt;a href=&quot;http://dx.doi.org/10.1002/mas.20115&quot;&gt;https://doi.org/10.1002/mas.20115&lt;/a&gt;, 2007.</mixed-citation>
</ref>
<ref id="ref10">
<label>10</label><mixed-citation publication-type="other" xlink:type="simple">Claeys, M., Iinuma, Y., Szmigielski, R., Surratt, J. D., Blockhuys, F., van Alsenoy, C., Boege, O., Sierau, B., Gomez-Gonzalez, Y., Vermeylen, R., van der Veken, P., Shahgholi, M., Chan, A. W. H., Herrmann, H., Seinfeld, J. H., and Maenhaut, W.: Terpenylic Acid and Related Compounds from the Oxidation of alpha-Pinene: Implications for New Particle Formation and Growth above Forests, Environ. Sci. Technol., 43, 6976–6982, &lt;a href=&quot;http://dx.doi.org/10.1021/es9007596&quot;&gt;https://doi.org/10.1021/es9007596&lt;/a&gt;, 2009.</mixed-citation>
</ref>
<ref id="ref11">
<label>11</label><mixed-citation publication-type="other" xlink:type="simple">Corrigan, A. L., Russell, L. M., Takahama, S., Äijälä, M., Ehn, M., Junninen, H., Rinne, J., Petäjä, T., Kulmala, M., Vogel, A. L., Hoffmann, T., Ebben, C. J., Geiger, F. M., Chhabra, P., Seinfeld, J. H., Worsnop, D. R., Song, W., Auld, J., and Williams, J.: Biogenic and biomass burning organic aerosol in a boreal forest at Hyytiälá, Finland, during HUMPPA-COPEC 2010, Atmos. Chem. Phys. Discuss., 13, 16151–16210, &lt;a href=&quot;http://dx.doi.org/10.5194/acpd-13-16151-2013&quot;&gt;https://doi.org/10.5194/acpd-13-16151-2013&lt;/a&gt;, 2013.</mixed-citation>
</ref>
<ref id="ref12">
<label>12</label><mixed-citation publication-type="other" xlink:type="simple">Dal Maso, M., Sogacheva, L., Aalto, P. P., Riipinen, I., Komppula, M., Tunved, P., Korhonen, L., Suur-Uski, V., Hirsikko, A., Kurten, T., Kerminen, V. M., Lihavainen, H., Viisanen, Y., Hansson, H.-C., and Kulmala, M.: Aerosol size distribution measurements at four Nordic field stations: identification, analysis and trajectory analysis of new particle formation bursts, Tellus B-, 59, 350–361, &lt;a href=&quot;http://dx.doi.org/10.1111/j.1600-0889.2007.00267.x&quot;&gt;https://doi.org/10.1111/j.1600-0889.2007.00267.x&lt;/a&gt;, 2007.</mixed-citation>
</ref>
<ref id="ref13">
<label>13</label><mixed-citation publication-type="other" xlink:type="simple">Docherty, K. S., Stone, E. A., Ulbrich, I. M., DeCarlo, P. F., Snyder, D. C., Schauer, J. J., Peltier, R. E., Weber, R. J., Murphy, S. M., Seinfeld, J. H., Grover, B. D., Eatough, D. J., and Jimenez, J. L.: Apportionment of Primary and Secondary Organic Aerosols in Southern California during the 2005 Study of Organic Aerosols in Riverside (SOAR-1), Environ. Sci. Technol., 42, 7655–7662, &lt;a href=&quot;http://dx.doi.org/10.1021/es8008166&quot;&gt;https://doi.org/10.1021/es8008166&lt;/a&gt;, 2008.</mixed-citation>
</ref>
<ref id="ref14">
<label>14</label><mixed-citation publication-type="other" xlink:type="simple">Donahue, N. M., Robinson, A. L., Stanier, C. O., and Pandis, S. N.: Coupled partitioning, dilution, and chemical aging of semivolatile organics, Environ. Sci. Technol., 40, 2635–2643, &lt;a href=&quot;http://dx.doi.org/10.1021/es052297c&quot;&gt;https://doi.org/10.1021/es052297c&lt;/a&gt;, 2006.</mixed-citation>
</ref>
<ref id="ref15">
<label>15</label><mixed-citation publication-type="other" xlink:type="simple">Donahue, N. M., Epstein, S. A., Pandis, S. N., and Robinson, A. L.: A two-dimensional volatility basis set: 1. organic-aerosol mixing thermodynamics, Atmos. Chem. Phys., 11, 3303–3318, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-11-3303-2011&quot;&gt;https://doi.org/10.5194/acp-11-3303-2011&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref16">
<label>16</label><mixed-citation publication-type="other" xlink:type="simple">Donahue, N. M., Kroll, J. H., Pandis, S. N., and Robinson, A. L.: A two-dimensional volatility basis set – Part 2: Diagnostics of organic-aerosol evolution, Atmos. Chem. Phys., 12, 615–634, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-12-615-2012&quot;&gt;https://doi.org/10.5194/acp-12-615-2012&lt;/a&gt;, 2012a.</mixed-citation>
</ref>
<ref id="ref17">
<label>17</label><mixed-citation publication-type="other" xlink:type="simple">Donahue, N. M., Henry, K. M., Mentel, T. F., Kiendler-Scharr, A., Spindler, C., Bohn, B., Brauers, T., Dorn, H. P., Fuchs, H., Tillmann, R., Wahner, A., Saathoff, H., Naumann, K.-H., Moehler, O., Leisner, T., Mueller, L., Reinnig, M.-C., Hoffmann, T., Salo, K., Hallquist, M., Frosch, M., Bilde, M., Tritscher, T., Barmet, P., Praplan, A. P., DeCarlo, P. F., Dommen, J., Prevot, A. S. H., and Baltensperger, U.: Aging of biogenic secondary organic aerosol via gas-phase OH radical reactions, P. Natl. Acad. Sci. USA, 109, 13503–13508, &lt;a href=&quot;http://dx.doi.org/10.1073/pnas.1115186109&quot;&gt;https://doi.org/10.1073/pnas.1115186109&lt;/a&gt;, 2012b.</mixed-citation>
</ref>
<ref id="ref18">
<label>18</label><mixed-citation publication-type="other" xlink:type="simple">Draxler, R. R. and Rolph G. D.: HYSPLIT (HYbrid Single-Particle Lagrangian Integrated Trajectory) Model access via NOAA ARL READY Website: &lt;a href=&quot;http://ready.arl.noaa.gov/HYSPLIT.php&quot;&gt;http://ready.arl.noaa.gov/HYSPLIT.php&lt;/a&gt;, NOAA Air Resources Laboratory, Silver Spring, MD, 2013.</mixed-citation>
</ref>
<ref id="ref19">
<label>19</label><mixed-citation publication-type="other" xlink:type="simple">Drewnick, F., Hings, S. S., DeCarlo, P., Jayne, J. T., Gonin, M., Fuhrer, K., Weimer, S., Jimenez, J. L., Demerjian, K. L., Borrmann, S., and Worsnop, D. R.: A new time-of-flight aerosol mass spectrometer (TOF-AMS) – Instrument description and first field deployment, Aerosol Sci. Technol., 39, 637–658, &lt;a href=&quot;http://dx.doi.org/10.1080/02786820500182040&quot;&gt;https://doi.org/10.1080/02786820500182040&lt;/a&gt;, 2005.</mixed-citation>
</ref>
<ref id="ref20">
<label>20</label><mixed-citation publication-type="other" xlink:type="simple">Geller, M. D., Biswas, S., Fine, P. A., and Sioutas, C.: A new compact aerosol concentrator for use in conjunction with low flow-rate continuous aerosol instrumentation, J. Aerosol Sci., 36, 1006–1022, &lt;a href=&quot;http://dx.doi.org/10.1016/j.jaerosci.2004.11.015&quot;&gt;https://doi.org/10.1016/j.jaerosci.2004.11.015&lt;/a&gt;, 2005.</mixed-citation>
</ref>
<ref id="ref21">
<label>21</label><mixed-citation publication-type="other" xlink:type="simple">Glasius, M., Duane, M., and Larsen, B. R.: Determination of polar terpene oxidation products in aerosols by liquid chromatography-ion trap mass spectrometry, J. Chromatography A, 833, 121–135, &lt;a href=&quot;http://dx.doi.org/10.1016/s0021-9673(98)01042-5&quot;&gt;https://doi.org/10.1016/s0021-9673(98)01042-5&lt;/a&gt;, 1999.</mixed-citation>
</ref>
<ref id="ref22">
<label>22</label><mixed-citation publication-type="other" xlink:type="simple">Glasius, M., Lahaniati, M., Calogirou, A., Di Bella, D., Jensen, N. R., Hjorth, J., Kotzias, D., and Larsen, B. R.: Carboxylic acids in secondary aerosols from oxidation of cyclic monoterpenes by ozone, Environ. Sci. Technol., 34, 1001–1010, &lt;a href=&quot;http://dx.doi.org/10.1021/es990445r&quot;&gt;https://doi.org/10.1021/es990445r&lt;/a&gt;, 2000.</mixed-citation>
</ref>
<ref id="ref23">
<label>23</label><mixed-citation publication-type="other" xlink:type="simple">Goldstein, A. H. and Galbally, I. E.: Known and unexplored organic constituents in the earth&apos;s atmosphere, Environ. Sci. Technol., 41, 1514–1521, &lt;a href=&quot;http://dx.doi.org/10.1021/es072476p&quot;&gt;https://doi.org/10.1021/es072476p&lt;/a&gt;, 2007.</mixed-citation>
</ref>
<ref id="ref24">
<label>24</label><mixed-citation publication-type="other" xlink:type="simple">Gómez-González, Y., Wang, W., Vermeylen, R., Chi, X., Neirynck, J., Janssens, I. A., Maenhaut, W., and Claeys, M.: Chemical characterisation of atmospheric aerosols during a 2007 summer field campaign at Brasschaat, Belgium: sources and source processes of biogenic secondary organic aerosol, Atmos. Chem. Phys., 12, 125–138, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-12-125-2012&quot;&gt;https://doi.org/10.5194/acp-12-125-2012&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref25">
<label>25</label><mixed-citation publication-type="other" xlink:type="simple">Hall, W. A., Pennington, M. R., and Johnston, M. V.: Molecular Transformations Accompanying the Aging of Laboratory Secondary Organic Aerosol, Environ. Sci. Technol., 47, 2230–2237, &lt;a href=&quot;http://dx.doi.org/10.1021/es303891q&quot;&gt;https://doi.org/10.1021/es303891q&lt;/a&gt;, 2013.</mixed-citation>
</ref>
<ref id="ref26">
<label>26</label><mixed-citation publication-type="other" xlink:type="simple">Hallquist, M., Wenger, J. C., Baltensperger, U., Rudich, Y., Simpson, D., Claeys, M., Dommen, J., Donahue, N. M., George, C., Goldstein, A. H., Hamilton, J. F., Herrmann, H., Hoffmann, T., Iinuma, Y., Jang, M., Jenkin, M. E., Jimenez, J. L., Kiendler-Scharr, A., Maenhaut, W., McFiggans, G., Mentel, Th. F., Monod, A., Prévôt, A. S. H., Seinfeld, J. H., Surratt, J. D., Szmigielski, R., and Wildt, J.: The formation, properties and impact of secondary organic aerosol: current and emerging issues, Atmos. Chem. Phys., 9, 5155–5236, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-9-5155-2009&quot;&gt;https://doi.org/10.5194/acp-9-5155-2009&lt;/a&gt;, 2009.</mixed-citation>
</ref>
<ref id="ref27">
<label>27</label><mixed-citation publication-type="other" xlink:type="simple">Hari, P. and Kulmala, M.: Station for measuring ecosystem-atmosphere relations (SMEAR II), Boreal Environ. Res., 10, 315–322, 2005.</mixed-citation>
</ref>
<ref id="ref28">
<label>28</label><mixed-citation publication-type="other" xlink:type="simple">Hoffmann, T., Bandur, R., Marggraf, U., and Linscheid, M.: Molecular composition of organic aerosols formed in the alpha-pinene/O-3 reaction: Implications for new particle formation processes, J. Geophys. Res.-Atmos., 103, 25569–25578, &lt;a href=&quot;http://dx.doi.org/10.1029/98jd01816&quot;&gt;https://doi.org/10.1029/98jd01816&lt;/a&gt;, 1998.</mixed-citation>
</ref>
<ref id="ref29">
<label>29</label><mixed-citation publication-type="other" xlink:type="simple">Hoffmann, T., Bandur, R., Hoffmann, S., and Warscheid, B.: Online characterization of gaseous and particulate organic analytes using atmospheric pressure chemical ionization mass spectrometry, Spectrochim. Acta, Part B, 57, 1635–1647, &lt;a href=&quot;http://dx.doi.org/10.1016/S0584-8547(02)00111-8&quot;&gt;https://doi.org/10.1016/S0584-8547(02)00111-8&lt;/a&gt;, 2002.</mixed-citation>
</ref>
<ref id="ref30">
<label>30</label><mixed-citation publication-type="other" xlink:type="simple">Iinuma, Y., Boege, O., Keywood, M., Gnauk, T., and Herrmann, H.: Diaterebic Acid Acetate and Diaterpenylic Acid Acetate: Atmospheric Tracers for Secondary Organic Aerosol Formation from 1,8-Cineole Oxidation, Environ. Sci. Technol., 43, 280–285, &lt;a href=&quot;http://dx.doi.org/10.1021/es802141v&quot;&gt;https://doi.org/10.1021/es802141v&lt;/a&gt;, 2009.</mixed-citation>
</ref>
<ref id="ref31">
<label>31</label><mixed-citation publication-type="other" xlink:type="simple">Jaoui, M. and Kamens, R. M.: Gaseous and particulate oxidation products analysis of a mixture of alpha-pinene plus beta-pinene/O-3/air in the absence of light and alpha-pinene plus beta-pinene/NOx/air in the presence of natural sunlight, J. Atmos. Chem., 44, 259–297, &lt;a href=&quot;http://dx.doi.org/10.1023/a:1022977427523&quot;&gt;https://doi.org/10.1023/a:1022977427523&lt;/a&gt;, 2003.</mixed-citation>
</ref>
<ref id="ref32">
<label>32</label><mixed-citation publication-type="other" xlink:type="simple">Jaoui, M., Corse, E., Kleindienst, T. E., Offenberg, J. H., Lewandowski, M., and Edney, E. O.: Analysis of secondary organic aerosol compounds from the photooxidation of d-limonene in the presence of NOX and their detection in ambient PM2.5, Environ. Sci. Technol., 40, 3819–3828, &lt;a href=&quot;http://dx.doi.org/10.1021/es052566z&quot;&gt;https://doi.org/10.1021/es052566z&lt;/a&gt;, 2006.</mixed-citation>
</ref>
<ref id="ref33">
<label>33</label><mixed-citation publication-type="other" xlink:type="simple">Jayne, J. T., Leard, D. C., Zhang, X. F., Davidovits, P., Smith, K. A., Kolb, C. E., and Worsnop, D. R.: Development of an aerosol mass spectrometer for size and composition analysis of submicron particles, Aerosol Sci. Technol., 33, 49–70, &lt;a href=&quot;http://dx.doi.org/10.1080/027868200410840&quot;&gt;https://doi.org/10.1080/027868200410840&lt;/a&gt;, 2000.</mixed-citation>
</ref>
<ref id="ref34">
<label>34</label><mixed-citation publication-type="other" xlink:type="simple">Jimenez, J. L., Jayne, J. T., Shi, Q., Kolb, C. E., Worsnop, D. R., Yourshaw, I., Seinfeld, J. H., Flagan, R. C., Zhang, X. F., Smith, K. A., Morris, J. W., and Davidovits, P.: Ambient aerosol sampling using the Aerodyne Aerosol Mass Spectrometer, J. Geophys. Res.-Atmos., 108, 8425, &lt;a href=&quot;http://dx.doi.org/10.1029/2001jd001213&quot;&gt;https://doi.org/10.1029/2001jd001213&lt;/a&gt;, 2003.</mixed-citation>
</ref>
<ref id="ref35">
<label>35</label><mixed-citation publication-type="other" xlink:type="simple">Jimenez, J. L., Canagaratna, M. R., Donahue, N. M., Prevot, A. S. H., Zhang, Q., Kroll, J. H., DeCarlo, P. F., Allan, J. D., Coe, H., Ng, N. L., Aiken, A. C., Docherty, K. S., Ulbrich, I. M., Grieshop, A. P., Robinson, A. L., Duplissy, J., Smith, J. D., Wilson, K. R., Lanz, V. A., Hueglin, C., Sun, Y. L., Tian, J., Laaksonen, A., Raatikainen, T., Rautiainen, J., Vaattovaara, P., Ehn, M., Kulmala, M., Tomlinson, J. M., Collins, D. R., Cubison, M. J., Dunlea, E. J., Huffman, J. A., Onasch, T. B., Alfarra, M. R., Williams, P. I., Bower, K., Kondo, Y., Schneider, J., Drewnick, F., Borrmann, S., Weimer, S., Demerjian, K., Salcedo, D., Cottrell, L., Griffin, R., Takami, A., Miyoshi, T., Hatakeyama, S., Shimono, A., Sun, J. Y., Zhang, Y. M., Dzepina, K., Kimmel, J. R., Sueper, D., Jayne, J. T., Herndon, S. C., Trimborn, A. M., Williams, L. R., Wood, E. C., Middlebrook, A. M., Kolb, C. E., Baltensperger, U., and Worsnop, D. R.: Evolution of Organic Aerosols in the Atmosphere, Science, 326, 1525–1529, &lt;a href=&quot;http://dx.doi.org/10.1126/science.1180353&quot;&gt;https://doi.org/10.1126/science.1180353&lt;/a&gt;, 2009.</mixed-citation>
</ref>
<ref id="ref36">
<label>36</label><mixed-citation publication-type="other" xlink:type="simple">Justesen, U.: Collision-induced fragmentation of deprotonated methoxylated flavonoids, obtained by electrospray ionization mass spectrometry, J. Mass Spectrom., 36, 169–178, &lt;a href=&quot;http://dx.doi.org/10.1002/jms.118&quot;&gt;https://doi.org/10.1002/jms.118&lt;/a&gt;, 2001.</mixed-citation>
</ref>
<ref id="ref37">
<label>37</label><mixed-citation publication-type="other" xlink:type="simple">Kalberer, M., Sax, M., and Samburova, V.: Molecular size evolution of oligomers in organic aerosols collected in urban atmospheres and generated in a smog chamber, Environ. Sci. Technol., 40, 5917–5922, &lt;a href=&quot;http://dx.doi.org/10.1021/es0525760&quot;&gt;https://doi.org/10.1021/es0525760&lt;/a&gt;, 2006.</mixed-citation>
</ref>
<ref id="ref38">
<label>38</label><mixed-citation publication-type="other" xlink:type="simple">Kessler, S. H., Smith, J. D., Che, D. L., Worsnop, D. R., Wilson, K. R., and Kroll, J. H.: Chemical Sinks of Organic Aerosol: Kinetics and Products of the Heterogeneous Oxidation of Erythritol and Levoglucosan, Environ. Sci. Technol., 44, 7005–7010, &lt;a href=&quot;http://dx.doi.org/10.1021/es101465m&quot;&gt;https://doi.org/10.1021/es101465m&lt;/a&gt;, 2010.</mixed-citation>
</ref>
<ref id="ref39">
<label>39</label><mixed-citation publication-type="other" xlink:type="simple">Kessler, S. H., Nah, T., Daumit, K. E., Smith, J. D., Leone, S. R., Kolb, C. E., Worsnop, D. R., Wilson, K. R., and Kroll, J. H.: OH-Initiated Heterogeneous Aging of Highly Oxidized Organic Aerosol, J. Phys. Chem. A, 116, 6358–6365, &lt;a href=&quot;http://dx.doi.org/10.1021/jp212131m&quot;&gt;https://doi.org/10.1021/jp212131m&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref40">
<label>40</label><mixed-citation publication-type="other" xlink:type="simple">Khwaja, H. A.: Atmospheric concentrations of carboxylic acids and related compounds at a semiurban site, Atmos. Environ., 29, 127–139, &lt;a href=&quot;http://dx.doi.org/10.1016/1352-2310(94)00211-3&quot;&gt;https://doi.org/10.1016/1352-2310(94)00211-3&lt;/a&gt;, 1995.</mixed-citation>
</ref>
<ref id="ref41">
<label>41</label><mixed-citation publication-type="other" xlink:type="simple">Kiss, G., Tombacz, E., Varga, B., Alsberg, T., and Persson, L.: Estimation of the average molecular weight of humic-like substances isolated from fine atmospheric aerosol, Atmos. Environ., 37, 3783–3794, &lt;a href=&quot;http://dx.doi.org/10.1016/s1352-2310(03)00468-0&quot;&gt;https://doi.org/10.1016/s1352-2310(03)00468-0&lt;/a&gt;, 2003.</mixed-citation>
</ref>
<ref id="ref42">
<label>42</label><mixed-citation publication-type="other" xlink:type="simple">Konovalov, I. B., Beekmann, M., Kuznetsova, I. N., Yurova, A., and Zvyagintsev, A. M.: Atmospheric impacts of the 2010 Russian wildfires: integrating modelling and measurements of an extreme air pollution episode in the Moscow region, Atmos. Chem. Phys., 11, 10031–10056, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-11-10031-2011&quot;&gt;https://doi.org/10.5194/acp-11-10031-2011&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref43">
<label>43</label><mixed-citation publication-type="other" xlink:type="simple">Kourtchev, I., Ruuskanen, T. M., Keronen, P., Sogacheva, L., Dal Maso, M., Reissell, A., Chi, X., Vermeylen, R., Kulmala, M., Maenhaut, W., and Claeys, M.: Determination of isoprene and alpha-/beta-pinene oxidation products in boreal forest aerosols from Hyytiala, Finland: diel variations and possible link with particle formation events, Plant Biol., 10, 138–149, &lt;a href=&quot;http://dx.doi.org/10.1055/s-2007-964945&quot;&gt;https://doi.org/10.1055/s-2007-964945&lt;/a&gt;, 2008.</mixed-citation>
</ref>
<ref id="ref44">
<label>44</label><mixed-citation publication-type="other" xlink:type="simple">Kourtchev, I., Fuller, S., Aalto, J., Ruuskanen, T. M., McLeod, M. W., Maenhaut, W., Jones, R., Kulmala, M., and Kalberer, M.: Molecular Composition of Boreal Forest Aerosol from Hyytiälä, Finland, Using Ultrahigh Resolution Mass Spectrometry, Environ. Sci. Technol., 47, 4069–4079, &lt;a href=&quot;http://dx.doi.org/10.1021/es3051636&quot;&gt;https://doi.org/10.1021/es3051636&lt;/a&gt;, 2013.</mixed-citation>
</ref>
<ref id="ref45">
<label>45</label><mixed-citation publication-type="other" xlink:type="simple">Kroll, J. H., Donahue, N. M., Jimenez, J. L., Kessler, S. H., Canagaratna, M. R., Wilson, K. R., Altieri, K. E., Mazzoleni, L. R., Wozniak, A. S., Bluhm, H., Mysak, E. R., Smith, J. D., Kolb, C. E., and Worsnop, D. R.: Carbon oxidation state as a metric for describing the chemistry of atmospheric organic aerosol, Nature Chemistry, 3, 133–139, &lt;a href=&quot;http://dx.doi.org/10.1038/nchem.948&quot;&gt;https://doi.org/10.1038/nchem.948&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref46">
<label>46</label><mixed-citation publication-type="other" xlink:type="simple">Kückelmann, U., Warscheid, S., and Hoffmann, T.: On-line characterization of organic aerosols formed from biogenic precursors using atmospheric pressure chemical ionization mass spectrometry, Anal. Chem., 72, 1905–1912, &lt;a href=&quot;http://dx.doi.org/10.1021/ac991178a&quot;&gt;https://doi.org/10.1021/ac991178a&lt;/a&gt;, 2000.</mixed-citation>
</ref>
<ref id="ref47">
<label>47</label><mixed-citation publication-type="other" xlink:type="simple">Kulmala, M., Hameri, K., Aalto, P. P., Makela, J. M., Pirjola, L., Nilsson, E. D., Buzorius, G., Rannik, U., Dal Maso, M., Seidl, W., Hoffman, T., Janson, R., Hansson, H. C., Viisanen, Y., Laaksonen, A., and O&apos;Dowd, C. D.: Overview of the international project on biogenic aerosol formation in the boreal forest (BIOFOR), Tellus B, 53, 324–343, &lt;a href=&quot;http://dx.doi.org/10.1034/j.1600-0889.2001.530402.x&quot;&gt;https://doi.org/10.1034/j.1600-0889.2001.530402.x&lt;/a&gt;, 2001.</mixed-citation>
</ref>
<ref id="ref48">
<label>48</label><mixed-citation publication-type="other" xlink:type="simple">Laskin, A., Laskin, J., and Nizkorodov, S. A.: Mass spectrometric approaches for chemical characterisation of atmospheric aerosols: critical review of the most recent advances, Environ. Chem., 9, 163–189, &lt;a href=&quot;http://dx.doi.org/10.1071/en12052&quot;&gt;https://doi.org/10.1071/en12052&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref49">
<label>49</label><mixed-citation publication-type="other" xlink:type="simple">Liang, C. K. and Pankow, J. F.: Gas/particle partitioning of organic compounds to environmental tobacco smoke: Partition coefficient measurements by desorption and comparison to urban particulate material, Environ. Sci. Technol., 30, 2800–2805, &lt;a href=&quot;http://dx.doi.org/10.1021/es960050x&quot;&gt;https://doi.org/10.1021/es960050x&lt;/a&gt;, 1996.</mixed-citation>
</ref>
<ref id="ref50">
<label>50</label><mixed-citation publication-type="other" xlink:type="simple">Ma, Y., Porter, R. A., Chappell, D., Russell, A. T., and Marston, G.: Mechanisms for the formation of organic acids in the gas-phase ozonolysis of 3-carene, Phys. Chem. Chem. Phys., 11, 4184–4197, &lt;a href=&quot;http://dx.doi.org/10.1039/b818750a&quot;&gt;https://doi.org/10.1039/b818750a&lt;/a&gt;, 2009.</mixed-citation>
</ref>
<ref id="ref51">
<label>51</label><mixed-citation publication-type="other" xlink:type="simple">Mitchum, R. K. and Korfmacher, W. A.: Atmospheric Pressure Ionization Mass Spectrometry, Anal. Chem., 55, 1485–1499, 1983.</mixed-citation>
</ref>
<ref id="ref52">
<label>52</label><mixed-citation publication-type="other" xlink:type="simple">Müller, L., Reinnig, M.-C., Naumann, K. H., Saathoff, H., Mentel, T. F., Donahue, N. M., and Hoffmann, T.: Formation of 3-methyl-1,2,3-butanetricarboxylic acid via gas phase oxidation of pinonic acid – a mass spectrometric study of SOA aging, Atmos. Chem. Phys., 12, 1483–1496, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-12-1483-2012&quot;&gt;https://doi.org/10.5194/acp-12-1483-2012&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref53">
<label>53</label><mixed-citation publication-type="other" xlink:type="simple">Net, S., Alvarez, E. G., Gligorovski, S., and Wortham, H.: Heterogeneous reactions of ozone with methoxyphenols, in presence and absence of light, Atmos. Environ., 45, 3007–3014, &lt;a href=&quot;http://dx.doi.org/10.1016/j.atmosenv.2011.03.026&quot;&gt;https://doi.org/10.1016/j.atmosenv.2011.03.026&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref54">
<label>54</label><mixed-citation publication-type="other" xlink:type="simple">Nilsson, E. D., Paatero, J., and Boy, M.: Effects of air masses and synoptic weather on aerosol formation in the continental boundary layer, Tellus B, 53, 462–478, &lt;a href=&quot;http://dx.doi.org/10.1034/j.1600-0889.2001.530410.x&quot;&gt;https://doi.org/10.1034/j.1600-0889.2001.530410.x&lt;/a&gt;, 2001.</mixed-citation>
</ref>
<ref id="ref55">
<label>55</label><mixed-citation publication-type="other" xlink:type="simple">Paatero, P. and Tapper, U.: Positive Matrix Factorization: a non-negative factor model with optimal utilization of error estimates of data values, Environmetrics, 5, 111–126, 1994.</mixed-citation>
</ref>
<ref id="ref56">
<label>56</label><mixed-citation publication-type="other" xlink:type="simple">Pankow, J. F.: An Absorption Model of Gas/Particle Partitioning of Organic Compounds in the Atmosphere, Atmos. Environ., 28, 189–193, &lt;a href=&quot;http://dx.doi.org/10.1016/1352-2310(94)90093-0&quot;&gt;https://doi.org/10.1016/1352-2310(94)90093-0&lt;/a&gt;, 1994.</mixed-citation>
</ref>
<ref id="ref57">
<label>57</label><mixed-citation publication-type="other" xlink:type="simple">Pankow, J. F.: On the ability of the gas/particle partitioning constant K-p to consider the effects of mean MW and the presence of high MW compounds, Atmos. Environ., 45, 1213–1216, &lt;a href=&quot;http://dx.doi.org/10.1016/j.atmosenv.2010.11.041&quot;&gt;https://doi.org/10.1016/j.atmosenv.2010.11.041&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref58">
<label>58</label><mixed-citation publication-type="other" xlink:type="simple">Pankow, J. F. and Asher, W. E.: SIMPOL.1: a simple group contribution method for predicting vapor pressures and enthalpies of vaporization of multifunctional organic compounds, Atmos. Chem. Phys., 8, 2773–2796, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-8-2773-2008&quot;&gt;https://doi.org/10.5194/acp-8-2773-2008&lt;/a&gt;, 2008.</mixed-citation>
</ref>
<ref id="ref59">
<label>59</label><mixed-citation publication-type="other" xlink:type="simple">Portin, H., Mielonen, T., Leskinen, A., Arola, A., Parjala, E., Romakkaniemi, S., Laaksonen, A., Lehtinen, K. E. J., and Komppula, M.: Biomass burning aerosols observed in Eastern Finland during the Russian wildfires in summer 2010 – Part 1: In-situ aerosol characterization, Atmos. Environ., 47, 269–278, &lt;a href=&quot;http://dx.doi.org/10.1016/j.atmosenv.2011.10.067&quot;&gt;https://doi.org/10.1016/j.atmosenv.2011.10.067&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref60">
<label>60</label><mixed-citation publication-type="other" xlink:type="simple">Pratt, K. A. and Prather, K. A.: Mass Spectrometry of Atmospheric Aerosols –- Recent Developments and Applications. Part II: On-line Mass Spectrometry Techniques, Mass Spectrom. Rev., 31, 17–48, &lt;a href=&quot;http://dx.doi.org/10.1002/mas.20330&quot;&gt;https://doi.org/10.1002/mas.20330&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref61">
<label>61</label><mixed-citation publication-type="other" xlink:type="simple">Riipinen, I., Yli-Juuti, T., Pierce, J. R., Petaja, T., Worsnop, D. R., Kulmala, M., and Donahue, N. M.: The contribution of organics to atmospheric nanoparticle growth, Nature Geosci., 5, 453–458, &lt;a href=&quot;http://dx.doi.org/10.1038/ngeo1499&quot;&gt;https://doi.org/10.1038/ngeo1499&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref62">
<label>62</label><mixed-citation publication-type="other" xlink:type="simple">Rolph, G. D.: Real-time Environmental Applications and Display sYstem (READY) Website: &lt;a href=&quot;http://ready.arl.noaa.gov&quot;&gt;http://ready.arl.noaa.gov&lt;/a&gt;, NOAA Air Resources Laboratory, Silver Spring, MD, 2013.</mixed-citation>
</ref>
<ref id="ref63">
<label>63</label><mixed-citation publication-type="other" xlink:type="simple">Rossignol, S., Chiappini, L., Perraudin, E., Rio, C., Fable, S., Valorso, R., and Doussin, J. F.: Development of a parallel sampling and analysis method for the elucidation of gas/particle partitioning of oxygenated semi-volatile organics: a limonene ozonolysis study, Atmos. Meas. Tech., 5, 1459–1489, &lt;a href=&quot;http://dx.doi.org/10.5194/amt-5-1459-2012&quot;&gt;https://doi.org/10.5194/amt-5-1459-2012&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref64">
<label>64</label><mixed-citation publication-type="other" xlink:type="simple">Russell, L. M., Takahama, S., Liu, S., Hawkins, L. N., Covert, D. S., Quinn, P. K., and Bates, T. S.: Oxygenated fraction and mass of organic aerosol from direct emission and atmospheric processing measured on the R/V &lt;i&gt;Ronald Brown &lt;/i&gt;during TEXAQS/GoMACCS 2006, J. Geophys. Res., 114, D00F05, &lt;a href=&quot;http://dx.doi.org/10.1029/2008JD011275&quot;&gt;https://doi.org/10.1029/2008JD011275&lt;/a&gt;, 2009.</mixed-citation>
</ref>
<ref id="ref65">
<label>65</label><mixed-citation publication-type="other" xlink:type="simple">Sabine, C. L., Heimann, M., Artaxo, P., Bakker, D. C. E., Chen, C. A., Field, C. B., Gruber, N., Le Quéré, C., Prinn, R., Richey, J. E., Romero Lankao, P., Satahaye J. A., and Valentin, R.: Current Status and Past Trends of the Global Carbon Cycle, in: The global carbon cycle: Integrating humans, climate, and the natural world, edited by: Field, C. B. and Raupach, M. R., SCOPE, 62, Island Press, Washington, 17–44, 2004.</mixed-citation>
</ref>
<ref id="ref66">
<label>66</label><mixed-citation publication-type="other" xlink:type="simple">Shiraiwa, M. and Seinfeld, J. H.: Equilibration timescale of atmospheric secondary organic aerosol partitioning, Geophys. Res. Lett., 39, L24801, &lt;a href=&quot;http://dx.doi.org/10.1029/2012GL054008&quot;&gt;https://doi.org/10.1029/2012GL054008&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref67">
<label>67</label><mixed-citation publication-type="other" xlink:type="simple">Shiraiwa, M., Ammann, M., Koop, T., and Pöschl, U.: Gas uptake and chemical aging of semisolid organic aerosol particles, P. Natl. Acad. Sci. USA, 108, 11003–11008, &lt;a href=&quot;http://dx.doi.org/10.1073/pnas.1103045108&quot;&gt;https://doi.org/10.1073/pnas.1103045108&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref68">
<label>68</label><mixed-citation publication-type="other" xlink:type="simple">Simoneit, B. R. T., Rogge, W. F., Mazurek, M. A., Standley, L. J., Hildemann, L. M., and Cass, G. R.: Lignin Pyrolysis Products, Lignans, and Resin Acids as Specific Tracers of Plant Classes in Emissions from Biomass Combustion, Environ. Sci. Technol., 27, 2533–2541, &lt;a href=&quot;http://dx.doi.org/10.1021/es00048a034&quot;&gt;https://doi.org/10.1021/es00048a034&lt;/a&gt;, 1993.</mixed-citation>
</ref>
<ref id="ref69">
<label>69</label><mixed-citation publication-type="other" xlink:type="simple">Solomon, S. (Ed.): The physical science basis: Contribution of Working Group I to the fourth assessment report of the Intergovernmental Panel on Climate Change, Assessment report/Intergovernmental Panel on Climate Change (IPCC), 4, Cambridge Univ. Press, Cambridge, 2007.</mixed-citation>
</ref>
<ref id="ref70">
<label>70</label><mixed-citation publication-type="other" xlink:type="simple">Spracklen, D. V., Bonn, B., and Carslaw, K. S.: Boreal forests, aerosols and the impacts on clouds and climate, Philos. T. Roy. Soc. a-Mathematical Physical and Engineering Sciences, 366, 4613–4626, &lt;a href=&quot;http://dx.doi.org/10.1098/rsta.2008.0201&quot;&gt;https://doi.org/10.1098/rsta.2008.0201&lt;/a&gt;, 2008.</mixed-citation>
</ref>
<ref id="ref71">
<label>71</label><mixed-citation publication-type="other" xlink:type="simple">Szmigielski, R., Surratt, J. D., Gomez-Gonzalez, Y., van der Veken, P., Kourtchev, I., Vermeylen, R., Blockhuys, F., Jaoui, M., Kleindienst, T. E., Lewandowski, M., Offenberg, J. H., Edney, E. O., Seinfeld, J. H., Maenhaut, W., and Claeys, M.: 3-methyl-1,2,3-butanetricarboxylic acid: An atmospheric tracer for terpene secondary organic aerosol, Geophys. Res. Lett., 34, L24811, &lt;a href=&quot;http://dx.doi.org/10.1029/2007gl031338&quot;&gt;https://doi.org/10.1029/2007gl031338&lt;/a&gt;, 2007.</mixed-citation>
</ref>
<ref id="ref72">
<label>72</label><mixed-citation publication-type="other" xlink:type="simple">Takahama, S., Johnson, A., and Russell, L. M.: Quantification of carboxylic acid and carbonyl functional groups in organic aerosol infrared absorbance spectra, Aerosol Sci. Technol., 47, 310–325, &lt;a href=&quot;http://dx.doi.org/10.1080/02786826.2012.752065&quot;&gt;https://doi.org/10.1080/02786826.2012.752065&lt;/a&gt;, 2013.</mixed-citation>
</ref>
<ref id="ref73">
<label>73</label><mixed-citation publication-type="other" xlink:type="simple">Virtanen, A., Joutsensaari, J., Koop, T., Kannosto, J., Yli-Pirila, P., Leskinen, J., Makela, J. M., Holopainen, J. K., Pöschl, U., Kulmala, M., Worsnop, D. R., and Laaksonen, A.: An amorphous solid state of biogenic secondary organic aerosol particles, Nature, 467, 824–827, &lt;a href=&quot;http://dx.doi.org/10.1038/nature09455&quot;&gt;https://doi.org/10.1038/nature09455&lt;/a&gt;, 2010.</mixed-citation>
</ref>
<ref id="ref74">
<label>74</label><mixed-citation publication-type="other" xlink:type="simple">Vogel, A. L., Äijälä, M., Brüggemann, M., Ehn, M., Junninen, H., Petäjä, T., Worsnop, D. R., Kulmala, M., Williams, J., and Hoffmann, T.: Online atmospheric pressure chemical ionization ion trap mass spectrometry (APCI-IT-MSn) for measuring organic acids in concentrated bulk aerosol – a laboratory and field study, Atmos. Meas. Tech., 6, 431–443, &lt;a href=&quot;http://dx.doi.org/10.5194/amt-6-431-2013&quot;&gt;https://doi.org/10.5194/amt-6-431-2013&lt;/a&gt;, 2013.</mixed-citation>
</ref>
<ref id="ref75">
<label>75</label><mixed-citation publication-type="other" xlink:type="simple">Warnke, J., Bandur, R., and Hoffmann, T.: Capillary-HPLC-ESI-MS/MS method for the determination of acidic products from the oxidation of monoterpenes in atmospheric aerosol samples, Anal. Bioanal. Chem., 385, 34–45, &lt;a href=&quot;http://dx.doi.org/10.1007/s00216-006-0340-6&quot;&gt;https://doi.org/10.1007/s00216-006-0340-6&lt;/a&gt;, 2006.</mixed-citation>
</ref>
<ref id="ref76">
<label>76</label><mixed-citation publication-type="other" xlink:type="simple">Warscheid, B. and Hoffmann, T.: Direct analysis of highly oxidised organic aerosol constituents by on-line ion trap mass spectrometry in the negative-ion mode, Rapid Communications in Mass Spectrometry, 16, 496–504, &lt;a href=&quot;http://dx.doi.org/10.1002/rcm.602&quot;&gt;https://doi.org/10.1002/rcm.602&lt;/a&gt;, 2002.</mixed-citation>
</ref>
<ref id="ref77">
<label>77</label><mixed-citation publication-type="other" xlink:type="simple">Williams, B. J., Goldstein, A. H., Kreisberg, N. M., and Hering, S. V.: In situ measurements of gas/particle-phase transitions for atmospheric semivolatile organic compounds, P. Natl. Acad. Sci. USA, 107, 6676–6681, &lt;a href=&quot;http://dx.doi.org/10.1073/pnas.0911858107&quot;&gt;https://doi.org/10.1073/pnas.0911858107&lt;/a&gt;, 2010.</mixed-citation>
</ref>
<ref id="ref78">
<label>78</label><mixed-citation publication-type="other" xlink:type="simple">Williams, J., Crowley, J., Fischer, H., Harder, H., Martinez, M., Petäjä, T., Rinne, J., Bäck, J., Boy, M., Dal Maso, M., Hakala, J., Kajos, M., Keronen, P., Rantala, P., Aalto, J., Aaltonen, H., Paatero, J., Vesala, T., Hakola, H., Levula, J., Pohja, T., Herrmann, F., Auld, J., Mesarchaki, E., Song, W., Yassaa, N., Nölscher, A., Johnson, A. M., Custer, T., Sinha, V., Thieser, J., Pouvesle, N., Taraborrelli, D., Tang, M. J., Bozem, H., Hosaynali-Beygi, Z., Axinte, R., Oswald, R., Novelli, A., Kubistin, D., Hens, K., Javed, U., Trawny, K., Breitenberger, C., Hidalgo, P. J., Ebben, C. J., Geiger, F. M., Corrigan, A. L., Russell, L. M., Ouwersloot, H. G., Vilà-Guerau de Arellano, J., Ganzeveld, L., Vogel, A., Beck, M., Bayerle, A., Kampf, C. J., Bertelmann, M., Köllner, F., Hoffmann, T., Valverde, J., González, D., Riekkola, M.-L., Kulmala, M., and Lelieveld, J.: The summertime Boreal forest field measurement intensive (HUMPPA-COPEC-2010): an overview of meteorological and chemical influences, Atmos. Chem. Phys., 11, 10599–10618, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-11-10599-2011&quot;&gt;https://doi.org/10.5194/acp-11-10599-2011&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref79">
<label>79</label><mixed-citation publication-type="other" xlink:type="simple">Yasmeen, F., Vermeylen, R., Szmigielski, R., Iinuma, Y., Böge, O., Herrmann, H., Maenhaut, W., and Claeys, M.: Terpenylic acid and related compounds: precursors for dimers in secondary organic aerosol from the ozonolysis of α- and β-pinene, Atmos. Chem. Phys., 10, 9383–9392, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-10-9383-2010&quot;&gt;https://doi.org/10.5194/acp-10-9383-2010&lt;/a&gt;, 2010.</mixed-citation>
</ref>
<ref id="ref80">
<label>80</label><mixed-citation publication-type="other" xlink:type="simple">Yasmeen, F., Szmigielski, R., Vermeylen, R., Gomez-Gonzalez, Y., Surratt, J. D., Chan, A. W. H., Seinfeld, J. H., Maenhaut, W., and Claeys, M.: Mass spectrometric characterization of isomeric terpenoic acids from the oxidation of alpha-pinene, beta-pinene, d-limonene, and Delta(3)-carene in fine forest aerosol, J. Mass Spectrom., 46, 425–442, &lt;a href=&quot;http://dx.doi.org/10.1002/jms.1911&quot;&gt;https://doi.org/10.1002/jms.1911&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref81">
<label>81</label><mixed-citation publication-type="other" xlink:type="simple">Yasmeen, F., Vermeylen, R., Maurin, N., Perraudin, E., Doussin, J.-F., and Claeys, M.: Characterisation of tracers for aging of α-pinene secondary organic aerosol using liquid chromatography/negaive ion electrospray ionisation mass spectrometry, Environ. Chem., 9, 236–246, &lt;a href=&quot;http://dx.doi.org/10.1071/EN11148&quot;&gt;https://doi.org/10.1071/EN11148&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref82">
<label>82</label><mixed-citation publication-type="other" xlink:type="simple">Yassaa, N., Song, W., Lelieveld, J., Vanhatalo, A., Bäck, J., and Williams, J.: Diel cycles of isoprenoids in the emissions of Norway spruce, four Scots pine chemotypes, and in Boreal forest ambient air during HUMPPA-COPEC-2010, Atmos. Chem. Phys., 12, 7215–7229, &lt;a href=&quot;http://dx.doi.org/10.5194/acp-12-7215-2012&quot;&gt;https://doi.org/10.5194/acp-12-7215-2012&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref83">
<label>83</label><mixed-citation publication-type="other" xlink:type="simple">Yatavelli, R. L. N., Lopez-Hilfiker, F., Wargo, J. D., Kimmel, J. R., Cubison, M. J., Bertram, T. H., Jimenez, J. L., Gonin, M., Worsnop, D. R., and Thornton, J. A.: A Chemical Ionization High-Resolution Time-of-Flight Mass Spectrometer Coupled to a Micro Orifice Volatilization Impactor (MOVI-HR-ToF-CIMS) for Analysis of Gas and Particle-Phase Organic Species, Aerosol Sci. Technol., 46, 1313–1327, &lt;a href=&quot;http://dx.doi.org/10.1080/02786826.2012.712236&quot;&gt;https://doi.org/10.1080/02786826.2012.712236&lt;/a&gt;, 2012.</mixed-citation>
</ref>
<ref id="ref84">
<label>84</label><mixed-citation publication-type="other" xlink:type="simple">Yu, J. Z., Flagan, R. C., and Seinfeld, J. H.: Identification of products containing -COOH, -OH, and -C=O in atmospheric oxidation of hydrocarbons, Environ. Sci. Technol., 32, 2357–2370, &lt;a href=&quot;http://dx.doi.org/10.1021/es980129x&quot;&gt;https://doi.org/10.1021/es980129x&lt;/a&gt;, 1998.</mixed-citation>
</ref>
<ref id="ref85">
<label>85</label><mixed-citation publication-type="other" xlink:type="simple">Yu, J. Z., Cocker, D. R., Griffin, R. J., Flagan, R. C., and Seinfeld, J. H.: Gas-phase ozone oxidation of monoterpenes: Gaseous and particulate products, J. Atmos. Chem., 34, 207–258, &lt;a href=&quot;http://dx.doi.org/10.1023/a:1006254930583&quot;&gt;https://doi.org/10.1023/a:1006254930583&lt;/a&gt;, 1999.</mixed-citation>
</ref>
<ref id="ref86">
<label>86</label><mixed-citation publication-type="other" xlink:type="simple">Zahardis, J., Geddes, S., and Petrucci, G. A.: Improved Understanding of Atmospheric Organic Aerosols via Innovations in Soft Ionization Aerosol Mass Spectrometry, Anal. Chem., 83, 2409–2415, &lt;a href=&quot;http://dx.doi.org/10.1021/ac102737k&quot;&gt;https://doi.org/10.1021/ac102737k&lt;/a&gt;, 2011.</mixed-citation>
</ref>
<ref id="ref87">
<label>87</label><mixed-citation publication-type="other" xlink:type="simple">Zhang, Q., Jimenez, J. L., Canagaratna, M. R., Allan, J. D., Coe, H., Ulbrich, I., Alfarra, M. R., Takami, A., Middlebrook, A. M., Sun, Y. L., Dzepina, K., Dunlea, E., Docherty, K., DeCarlo, P. F., Salcedo, D., Onasch, T., Jayne, J. T., Miyoshi, T., Shimono, A., Hatakeyama, S., Takegawa, N., Kondo, Y., Schneider, J., Drewnick, F., Borrmann, S., Weimer, S., Demerjian, K., Williams, P., Bower, K., Bahreini, R., Cottrell, L., Griffin, R. J., Rautiainen, J., Sun, J. Y., Zhang, Y. M., and Worsnop, D. R.: Ubiquity and dominance of oxygenated species in organic aerosols in anthropogenically-influenced Northern Hemisphere midlatitudes, Geophys. Res. Lett., 34, L13801, &lt;a href=&quot;http://dx.doi.org/10.1029/2007gl029979&quot;&gt;https://doi.org/10.1029/2007gl029979&lt;/a&gt;, 2007.</mixed-citation>
</ref>
<ref id="ref88">
<label>88</label><mixed-citation publication-type="other" xlink:type="simple">Zhang, R.: Getting to the Critical Nucleus of Aerosol Formation, Science, 328, 1366–1367, &lt;a href=&quot;http://dx.doi.org/10.1126/science.1189732&quot;&gt;https://doi.org/10.1126/science.1189732&lt;/a&gt;, 2010.</mixed-citation>
</ref>
</ref-list>
</back>
</article>