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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-9-1971-2009</article-id>
<title-group>
<article-title>Mixing ratios and eddy covariance flux measurements of volatile organic compounds from an urban canopy (Manchester, UK)</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Langford</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>Davison</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>Nemitz</surname>
<given-names>E.</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>Hewitt</surname>
<given-names>C. N.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Centre for Ecology &amp; Hydrology (CEH) Edinburgh, Bush Estate, Penicuik, EH26 0QB, UK</addr-line>
</aff>
<pub-date pub-type="epub">
<day>19</day>
<month>03</month>
<year>2009</year>
</pub-date>
<volume>9</volume>
<issue>6</issue>
<fpage>1971</fpage>
<lpage>1987</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/9/1971/2009/acp-9-1971-2009.html">This article is available from http://www.atmos-chem-phys.net/9/1971/2009/acp-9-1971-2009.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/9/1971/2009/acp-9-1971-2009.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/9/1971/2009/acp-9-1971-2009.pdf</self-uri>
<abstract>
<p>Mixing ratios and fluxes of six selected volatile organic compounds (VOCs)
were measured above the city of Manchester (UK) during the summer of 2006. A
proton transfer reaction-mass spectrometer was used for the measurement of
mixing ratios, and fluxes were calculated from these using both the disjunct
and the virtual disjunct eddy covariance techniques. The two flux systems,
which operated in alternate half hours, showed good agreement, with &lt;i&gt;R&lt;sup&gt;2&lt;/sup&gt;&lt;/i&gt;
values ranging between 0.74 and 0.9 for the individual analytes. On average,
fluxes measured in the disjunct mode were approximately 20% lower than those
measured in the virtual mode. This difference is due to both the dampening of
the VOC signal by the disjunct flux sampler and carry over from one sample to
the next. Correcting for these effects reduced the difference to less than
7%. Observed fluxes are thought to be largely controlled by anthropogenic
sources, with vehicle emissions the major contributor. However, both
evaporative and biogenic emissions may account for some of the VOCs present.
Concentrations and fluxes of the oxygenated compounds were highest on
average, ranging between 0.15 to 1 mg m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; h&lt;sup&gt;&amp;minus;1&lt;/sup&gt;; the fluxes of
aromatic compounds were lower, between 0.12 to 0.28 mg m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; h&lt;sup&gt;&amp;minus;1&lt;/sup&gt;.
The observed fluxes were up-scaled to give city wide emission estimates for
each compound and the results compared to estimates made by the National
Atmospheric Emission Inventory (NAEI) for the same flux footprint. Fluxes of
toluene and benzene compared most closely differing by approximately 50%,
while in contrast the oxygenated fluxes were found to be between 3.6–6.3
times larger than the annual average predicted by the NAEI.</p>
</abstract>
<counts><page-count count="17"/></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"> Ammann, C., Brunner, A., Spirig, C., and Neftel, A.: Technical note: Water vapour concentration and flux measurements with PTR-MS, Atmos. Chem. Phys., 6, 4643–4651, 2006. </mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple"> Anderson, L. G., Lanning, J. A., Barrell, R., Miyagishima, J., Jones, R. H., and Wolfe, P.: Sources and sinks of formaldehyde and acetaldehyde: An analysis of Denver&apos;s ambient concentration data, Atmos. Environ., 30, 2113–2123, 1996. </mixed-citation>
</ref>
<ref id="ref3">
<label>3</label><mixed-citation publication-type="other" xlink:type="simple"> Atkinson, R.: Atmospheric chemistry of VOC and NO&lt;sub&gt;x&lt;/sub&gt;, Atmos. Environ., 34, 2063–2101, 2000. </mixed-citation>
</ref>
<ref id="ref4">
<label>4</label><mixed-citation publication-type="other" xlink:type="simple"> Aubinet, M., Chermanne, B., Vandenhaute, M., Longdoz, B., Yernaux, M., and Laitat, E.: Long term carbon dioxide exchange above a mixed forest in the Belgian Ardennes, Agr. Forest Meteorol., 108, 293–315, 2001. </mixed-citation>
</ref>
<ref id="ref5">
<label>5</label><mixed-citation publication-type="other" xlink:type="simple"> Borbon, A., Fontaine, H., Veillerot, M., Locoge, N., Galloo, J. C., and Guillermo, R.: An investigation into the traffic-related fraction of isoprene at an urban location, Atmos. Environ., 35, 3749–3760, 2001. </mixed-citation>
</ref>
<ref id="ref6">
<label>6</label><mixed-citation publication-type="other" xlink:type="simple"> Bowling, D. R., Turnipseed, A. A., Delany, A. C., Baldocchi, D. D., Greenberg, J. P., and Monson, R. K.: The use of relaxed eddy accumulation to measure biosphere-atmosphere exchange of isoprene and of other biological trace gases, Oecologia, 116, 306–315, 1998. </mixed-citation>
</ref>
<ref id="ref7">
<label>7</label><mixed-citation publication-type="other" xlink:type="simple"> Brunner, A., Ammann, C., Neftel, A., and Spirig, C.: Methanol exchange between grassland and the atmosphere, Biogeosciences, 4, 395–410, 2007. </mixed-citation>
</ref>
<ref id="ref8">
<label>8</label><mixed-citation publication-type="other" xlink:type="simple"> Businger, J. A. and Oncley, S. P.: Flux measurement with conditional sampling, J. Atmos. Ocean. Tech., 7, 349–352, 1990. </mixed-citation>
</ref>
<ref id="ref9">
<label>9</label><mixed-citation publication-type="other" xlink:type="simple"> Caplain, I., Cazier, F., Nouali, H., Mercier, A., Dechaux, J. C., Nollet, V., Journard, R., Andre, J. M., and Vidon, R.: Emissions of unregulated pollutants from European gasoline and diesel passenger cars, Atmos. Environ., 40, 5954–5966, 2006. </mixed-citation>
</ref>
<ref id="ref10">
<label>10</label><mixed-citation publication-type="other" xlink:type="simple"> Chiang, H. L., Hwu, C. S., Chen, S. Y., Wu, M. C., Ma, S. Y., and Huang, Y. S.: Emission factors and characteristics of criteria pollutants and volatile organic compounds (VOCs) in a freeway tunnel study, Sci. Total Environ., 381, 200–211, 2007. </mixed-citation>
</ref>
<ref id="ref11">
<label>11</label><mixed-citation publication-type="other" xlink:type="simple"> Christian, T. J., Kleiss, B., Yokelson, R. J., Holzinger, R., Crutzen, P. J., Hao, W. M., Shirai, T., and Blake, D. R.: Comprehensive laboratory measurements of biomass-burning emissions: 2. First intercomparison of open-path FTIR, PTR-MS, and GC-MS/FID/ECD, J. Geophys. Res.-Atmos., 109, D02311, doi:10.1029/2003JD003874, 2004. </mixed-citation>
</ref>
<ref id="ref12">
<label>12</label><mixed-citation publication-type="other" xlink:type="simple"> Ciccioli, P., Brancaleoni, E., Frattoni, M., Marta, S., Brachetti, A., Vitullo, M., Tirone, G., and Valentini, R.: Relaxed eddy accumulation, a new technique for measuring emission and deposition fluxes of volatile organic compounds by capillary gas chromatography and mass spectrometry, J. Chromatogr A, 985, 283–296, 2003. </mixed-citation>
</ref>
<ref id="ref13">
<label>13</label><mixed-citation publication-type="other" xlink:type="simple"> de Gouw, J. and Warneke, C.: Measurements of volatile organic compounds in the Earth&apos;s atmosphere using proton-transfer-reaction mass spectrometry, Mass Spectrom. Rev., 26, 223–257, 2007. </mixed-citation>
</ref>
<ref id="ref14">
<label>14</label><mixed-citation publication-type="other" xlink:type="simple"> de Gouw, J., Warneke, C., Karl, T., Eerdekens, G., van der Veen, C., and Fall, R.: Sensitivity and specificity of atmospheric trace gas detection by proton-transfer-reaction mass spectrometry, Int. J. Mass Spectrom., 223, 365–382, 2003. </mixed-citation>
</ref>
<ref id="ref15">
<label>15</label><mixed-citation publication-type="other" xlink:type="simple"> de Gouw, J. A., Howard, C. J., Custer, T. G., Baker, B. M., and Fall, R.: Proton-transfer chemical-ionization mass spectrometry allows real-time analysis of volatile organic compounds released from cutting and drying of crops, Environ. Sci. Technol., 34, 2640–2648, 2000. </mixed-citation>
</ref>
<ref id="ref16">
<label>16</label><mixed-citation publication-type="other" xlink:type="simple"> Dollard, G. J., Dumitrean, P., Telling, S., Dixon, J., and Derwent, R. G.: Observed trends in ambient concentrations of C-2-C-8 hydrocarbons in the United Kingdom over the period from 1993 to 2004, Atmos. Environ., 41, 2559–2569, 2007. </mixed-citation>
</ref>
<ref id="ref17">
<label>17</label><mixed-citation publication-type="other" xlink:type="simple"> Dorsey, J. R., Nemitz, E., Gallagher, M. W., Fowler, D., Williams, P. I., Bower, K. N., and Beswick, K. M.: Direct measurements and parameterisation of aerosol flux, concentration and emission velocity above a city, Atmos. Environ., 36, 791–800, 2002. </mixed-citation>
</ref>
<ref id="ref18">
<label>18</label><mixed-citation publication-type="other" xlink:type="simple"> Fairall, C. W.: Interpretation of eddy-correlation measurements of particulate deposition and aerosol flux, Atmos. Environ., 18, 1329–1337, 1984. </mixed-citation>
</ref>
<ref id="ref19">
<label>19</label><mixed-citation publication-type="other" xlink:type="simple"> Famulari, D., Nemitz, E., Di Marco, C., Phillips, G. J., Thomas, R., House, E., and Fowler, D.: Eddy-covariance measurements of nitrous oxide fluxes above a city, Agr. Forest Meteorol., in review, 2009. </mixed-citation>
</ref>
<ref id="ref20">
<label>20</label><mixed-citation publication-type="other" xlink:type="simple"> Filella, I. and Penuelas, J.: Daily, weekly, and seasonal time courses of VOC concentrations in a semi-urban area near Barcelona, Atmos. Environ., 40, 7752–7769, 2006. </mixed-citation>
</ref>
<ref id="ref21">
<label>21</label><mixed-citation publication-type="other" xlink:type="simple"> Friedrich, R. and Obermeier, A.: Anthropogenic Emissions of Volatile Organic Compounds, in: Reactive Hydrocarbons in the Atmosphere, edited by: Hewitt, C. N., Academic Press, California, 1–39, 1999. </mixed-citation>
</ref>
<ref id="ref22">
<label>22</label><mixed-citation publication-type="other" xlink:type="simple"> Gallagher, M. W., Clayborough, R., Beswick, K. M., Hewitt, C. N., Owen, S., Moncrieff, J., and Pilegaard, K.: Assessment of a relaxed eddy accumulation for measurements of fluxes of biogenic volatile organic compounds: Study over arable crops and a mature beech forest, Atmos. Environ., 34, 2887–2899, 2000. </mixed-citation>
</ref>
<ref id="ref23">
<label>23</label><mixed-citation publication-type="other" xlink:type="simple"> Grabmer, W., Graus, M., Lindinger, C., Wisthaler, A., Rappengluck, B., Steinbrecher, R., and Hansel, A.: Disjunct eddy covariance measurements of monoterpene fluxes from a norway spruce forest using PTR-MS, Int. J. Mass Spectrom., 239, 111–115, 2004. </mixed-citation>
</ref>
<ref id="ref24">
<label>24</label><mixed-citation publication-type="other" xlink:type="simple"> Greenberg, J. P., Guenther, A., Harley, P., Otter, L., Veenendaal, E. M., Hewitt, C. N., James, A. E., and Owen, S. M.: Eddy flux and leaf-level measurements of biogenic VOC emissions from mopane woodland of Botswana, J. Geophys. Res.-Atmos., 108(D13), 8466, doi:10.1029/2002JD002317, 2003. </mixed-citation>
</ref>
<ref id="ref25">
<label>25</label><mixed-citation publication-type="other" xlink:type="simple"> Grosjean, D., Grosjean, E., and Moreira, L. F. R.: Speciated ambient carbonyls in Rio de Janeiro, Brazil, Environ. Sci. Technol., 36, 1389-1395, 2002. </mixed-citation>
</ref>
<ref id="ref26">
<label>26</label><mixed-citation publication-type="other" xlink:type="simple"> Grosjean, E., Grosjean, D., Fraser, M. P., and Cass, G. R.: Air quality model evaluation data for organics. 2. C-1-C-14 carbonyls in Los Angeles air, Environ. Sci. Technol., 30, 2687–2703, 1996. </mixed-citation>
</ref>
<ref id="ref27">
<label>27</label><mixed-citation publication-type="other" xlink:type="simple"> Guenther, A., Geron, C., Pierce, T., Lamb, B., Harley, P., and Fall, R.: Natural emissions of non-methane volatile organic compounds; carbon monoxide, and oxides of nitrogen from North America, Atmos. Environ., 34, 2205–2230, 2000. </mixed-citation>
</ref>
<ref id="ref28">
<label>28</label><mixed-citation publication-type="other" xlink:type="simple"> Hayward, S., Hewitt, C. N., Sartin, J. H., and Owen, S. M.: Performance characteristics and applications of a proton transfer reaction-mass spectrometer for measuring volatile organic compounds in ambient air, Environ. Sci. Technol., 36, 1554–1560, 2002. </mixed-citation>
</ref>
<ref id="ref29">
<label>29</label><mixed-citation publication-type="other" xlink:type="simple"> Heeb, N. V., Forss, A. M., Bach, C., Reimann, S., Herzog, A., and Jackle, H. W.: A comparison of benzene, toluene and C-2-benzenes mixing ratios in automotive exhaust and in the suburban atmosphere during the introduction of catalytic converter technology to the Swiss car fleet, Atmos. Environ., 34, 3103–3116, 2000. </mixed-citation>
</ref>
<ref id="ref30">
<label>30</label><mixed-citation publication-type="other" xlink:type="simple"> Holzinger, R., Jordan, A., Hansel, A., and Lindinger, W.: Methanol measurements in the lower troposphere near Innsbruck (047&amp;deg;16´ N; 011&amp;deg;24´ E), Austria, Atmos. Environ., 35, 2525–2532, 2001. </mixed-citation>
</ref>
<ref id="ref31">
<label>31</label><mixed-citation publication-type="other" xlink:type="simple"> Horst, T. W.: A simple formula for attenuation of eddy fluxes measured with first-order-response scalar sensors, Bound.-Lay. Meteorol., 82, 219–233, 1997. </mixed-citation>
</ref>
<ref id="ref32">
<label>32</label><mixed-citation publication-type="other" xlink:type="simple"> Hurst, D. F., Griffith, D. W. T., and Cook, G. D.: Trace gas emissions from biomass burning in tropical Australian savannas, J. Geophys. Res.-Atmos., 99, 16 441–16 456, 1994. </mixed-citation>
</ref>
<ref id="ref33">
<label>33</label><mixed-citation publication-type="other" xlink:type="simple"> Hwa, M. Y., Hsieh, C. C., Wu, T. C., and Chang, L. F. W.: Real-world vehicle emissions and VOCs profile in the Taipei tunnel located at Taiwan Taipei area, Atmos. Environ., 36, 1993–2002, 2002. </mixed-citation>
</ref>
<ref id="ref34">
<label>34</label><mixed-citation publication-type="other" xlink:type="simple"> Jobson, B. T., Alexander, M. L., Maupin, G. D., and Muntean, G. G.: On-line analysis of organic compounds in diesel exhaust using a proton transfer reaction mass spectrometer (PTR-MS), Int. J. Mass Spectrom., 245, 78–89, 2005. </mixed-citation>
</ref>
<ref id="ref35">
<label>35</label><mixed-citation publication-type="other" xlink:type="simple"> Karl, T. G., Spirig, C., Rinne, J., Stroud, C., Prevost, P., Greenberg, J., Fall, R., and Guenther, A.: Virtual disjunct eddy covariance measurements of organic compound fluxes from a subalpine forest using proton transfer reaction mass spectrometry, Atmos. Chem. Phys., 2, 279–291, 2002. </mixed-citation>
</ref>
<ref id="ref36">
<label>36</label><mixed-citation publication-type="other" xlink:type="simple"> Karl, T., Guenther, A., Lindinger, C., Jordan, A., Fall, R., and Lindinger, W.: Eddy covariance measurements of oxygenated volatile organic compound fluxes from crop harvesting using a redesigned proton-transfer-reaction mass spectrometer, J. Geophys. Res.-Atmos., 106, 24 157–24 167, 2001. </mixed-citation>
</ref>
<ref id="ref37">
<label>37</label><mixed-citation publication-type="other" xlink:type="simple"> Kato, S., Miyakawa, Y., Kaneko, T., and Kajii, Y.: Urban air measurements using PTR-MS in Tokyo area and comparison with GC-FID measurements, Int. J. Mass Spectrom., 235, 103–110, 2004. </mixed-citation>
</ref>
<ref id="ref38">
<label>38</label><mixed-citation publication-type="other" xlink:type="simple"> Kljun, N., Calanca, P., Rotachhi, M. W., and Schmid, H. P.: A simple parameterisation for flux footprint predictions, Bound.-Lay. Meteorol., 112, 503–523, 2004. </mixed-citation>
</ref>
<ref id="ref39">
<label>39</label><mixed-citation publication-type="other" xlink:type="simple"> Kreuzwieser, J., Scheerer, U., and Rennenberg, H.: Metabolic origin of acetaldehyde emitted by Poplar (\textitPopulus tremula x \textitP-alba) trees, J. Exp. Bot., 50, 757–765, 1999. </mixed-citation>
</ref>
<ref id="ref40">
<label>40</label><mixed-citation publication-type="other" xlink:type="simple"> Kristensen, L., Mann, J., Oncley, S. P., and Wyngaard, J. C.: How close is close enough when measuring scalar fluxes with displaced sensors?, J. Atmos. Ocean. Tech., 14, 814–821, 1997. </mixed-citation>
</ref>
<ref id="ref41">
<label>41</label><mixed-citation publication-type="other" xlink:type="simple"> Lee, A., Schade, G. W., Holzinger, R., and Goldstein, A. H.: A comparison of new measurements of total monoterpene flux with improved measurements of speciated monoterpene flux, Atmos. Chem. Phys., 5, 505–513, 2005. </mixed-citation>
</ref>
<ref id="ref42">
<label>42</label><mixed-citation publication-type="other" xlink:type="simple"> Lenschow, D. H., Mann, J., and Kristensen, L.: How long is long enough when measuring fluxes and other turbulence statistics, J. Atmos. Ocean. Tech., 11, 661–673, 1994. </mixed-citation>
</ref>
<ref id="ref43">
<label>43</label><mixed-citation publication-type="other" xlink:type="simple"> Lenschow, D. H.: Micrometeorological techniques for measuring biosphere-atmosphere trace gas exchangei in: Biogenic Trace Gases: Measuring Emissions from Soil and Water, edited by: Matson, P. A., London, Blackwell, 126–163, 1995. </mixed-citation>
</ref>
<ref id="ref44">
<label>44</label><mixed-citation publication-type="other" xlink:type="simple"> Lindinger, W., Hansel, A., and Jordan, A.: Proton-transfer-reaction mass spectrometry (PTR-MS): On-line monitoring of volatile organic compounds at pptv levels, Chem. Soc. Rev., 27, 347–354, 1998. </mixed-citation>
</ref>
<ref id="ref45">
<label>45</label><mixed-citation publication-type="other" xlink:type="simple"> Lipari, F., Dasch, J. M., and Scruggs, W. F.: Aldehyde emissions from wood-burning fireplaces, Environ. Sci. Technol., 18, 326–330, 1984. </mixed-citation>
</ref>
<ref id="ref46">
<label>46</label><mixed-citation publication-type="other" xlink:type="simple"> Martin, C. L., Longley, I. D., Dorsey, J. R., Thomas, R. M., Gallagher M. W., and Nemitz, E.: Ultrafine particle fluxes above four major European cities, Atmos. Environ., in press, doi:10.1016/j.atmosenv.2008.10.009, 2008. </mixed-citation>
</ref>
<ref id="ref47">
<label>47</label><mixed-citation publication-type="other" xlink:type="simple"> Nemitz, E., Hargreaves, K. J., McDonald, A. G., Dorsey, J. R., and Fowler, D.: Meteorological measurements of the urban heat budget and CO&lt;sub&gt;2&lt;/sub&gt; emissions on a city scale, Environ. Sci. Technol., 36, 3139–3146, 2002. </mixed-citation>
</ref>
<ref id="ref48">
<label>48</label><mixed-citation publication-type="other" xlink:type="simple"> Oke, T. R.: Towards better scientific communication in urban climate, Theor. Appl. Climatol., 84, 179–190, 2006. </mixed-citation>
</ref>
<ref id="ref49">
<label>49</label><mixed-citation publication-type="other" xlink:type="simple"> Olofsson, M., Ek-Olausson, B., Ljungstrom, E., and Langer, S.: Flux of organic compounds from grass measured by relaxed eddy accumulation technique, J. Environ. Monitor., 5, 963–970, 2003. </mixed-citation>
</ref>
<ref id="ref50">
<label>50</label><mixed-citation publication-type="other" xlink:type="simple"> Park, C., Schade, G., and Boedeker, I.: VOC flux measurements using a novel relaxed eddy accumulation GC-FID system in urban Houston, Texas, Eos Trans. AGU, 89(53), Fall Meet. Suppl., Abstract A41F-0178, 2008. </mixed-citation>
</ref>
<ref id="ref51">
<label>51</label><mixed-citation publication-type="other" xlink:type="simple"> Possanzini, M., Dipalo, V., Petricca, M., Fratarcangeli, R., and Brocco, D.: Measurements of lower carbonyls in Rome ambient air, Atmos. Environ., 30, 3757–3764, 1996. </mixed-citation>
</ref>
<ref id="ref52">
<label>52</label><mixed-citation publication-type="other" xlink:type="simple"> Rinne, H. J. I., Delany, A. C., Greenberg, J. P., and Guenther, A. B.: A true eddy accumulation system for trace gas fluxes using disjunct eddy sampling method, J. Geophys. Res.-Atmos., 105, 24 791–24 798, 2000. </mixed-citation>
</ref>
<ref id="ref53">
<label>53</label><mixed-citation publication-type="other" xlink:type="simple"> Rinne, H. J. I., Guenther, A. B., Warneke, C., de Gouw, J. A., and Luxembourg, S. L.: Disjunct eddy covariance technique for trace gas flux measurements, Geophys. Res. Lett., 28, 3139–3142, 2001. </mixed-citation>
</ref>
<ref id="ref54">
<label>54</label><mixed-citation publication-type="other" xlink:type="simple"> Schween, J. H., Dlugi, R., Hewitt, C. N., and Foster, P.: Determination and accuracy of VOC-fluxes above the pine/oak forest at Castelporziano, Atmos. Environ., 31, 199–215, 1997. </mixed-citation>
</ref>
<ref id="ref55">
<label>55</label><mixed-citation publication-type="other" xlink:type="simple"> Sigsby, J. E., Tejada, S., Ray, W., Lang, J. M., and Duncan, J. W.: Volatile organic-compound emissions from 46~in-use passenger cars, Environ. Sci. Technol., 21, 466–475, 1987. </mixed-citation>
</ref>
<ref id="ref56">
<label>56</label><mixed-citation publication-type="other" xlink:type="simple"> Singh, H. B., Ohara, D., Herlth, D., Sachse, W., Blake, D. R., Bradshaw, J. D., Kanakidou, M., and Crutzen, P. J.: Acetone in the atmosphere – distribution, sources, and sinks, J. Geophys. Res.-Atmos., 99, 1805–1819, 1994. </mixed-citation>
</ref>
<ref id="ref57">
<label>57</label><mixed-citation publication-type="other" xlink:type="simple"> Spirig, C., Neftel, A., Ammann, C., Dommen, J., Grabmer, W., Thielmann, A., Schaub, A., Beauchamp, J., Wisthaler, A., and Hansel, A.: Eddy covariance flux measurements of biogenic VOCs during ECHO 2003 using proton transfer reaction mass spectrometry, Atmos. Chem. Phys., 5, 465–481, 2005. </mixed-citation>
</ref>
<ref id="ref58">
<label>58</label><mixed-citation publication-type="other" xlink:type="simple"> Tani, A., Nozoe, S., Aoki, M., and Hewitt, C. N.: Monoterpene fluxes measured above a Japanese red pine forest at Oshiba plateau, Japan, Atmos. Environ., 36, 3391–3402, 2002. </mixed-citation>
</ref>
<ref id="ref59">
<label>59</label><mixed-citation publication-type="other" xlink:type="simple"> Turnipseed, A. A., Pressley, S. N., Karl, T., Lamb, B., Nemitz, E., Allwine, E., Cooper, W. A., Shertz, S., and Guenther, A. B.: The use of disjunct eddy sampling methods for the determination of ecosystem level fluxes of trace gases, Atmos. Chem. Phys., 9, 981–994, 2009. </mixed-citation>
</ref>
<ref id="ref60">
<label>60</label><mixed-citation publication-type="other" xlink:type="simple"> Velasco, E., Lamb, B., Pressley, S., Allwine, E., Westberg, H., Jobson, B. T., Alexander, M., Prazeller, P., Molina, L., and Molina, M.: Flux measurements of volatile organic compounds from an urban landscape, Geophys. Res. Lett., 32, L20802, doi:10.1029/2005GL023356, 2005. </mixed-citation>
</ref>
<ref id="ref61">
<label>61</label><mixed-citation publication-type="other" xlink:type="simple"> Warneke, C., van der Veen, C., Luxembourg, S., de Gouw, J. A., and Kok, A.: Measurements of benzene and toluene in ambient air using proton-transfer-reaction mass spectrometry: Calibration, humidity dependence, and field intercomparison, Int. J. Mass Spectrom., 207, 167–182, 2001. </mixed-citation>
</ref>
<ref id="ref62">
<label>62</label><mixed-citation publication-type="other" xlink:type="simple"> Warneke, C., Luxembourg, S. L., de Gouw, J. A., Rinne, H. J. I., Guenther, A. B., and Fall, R.: Disjunct eddy covariance measurements of oxygenated volatile organic compounds fluxes from an alfalfa field before and after cutting, J. Geophys. Res.-Atmos., 107(D8), 4067, doi:10.1029/2001JD000594, 2002. </mixed-citation>
</ref>
<ref id="ref63">
<label>63</label><mixed-citation publication-type="other" xlink:type="simple"> Warneke, C., Karl, T., Judmaier, H., Hansel, A., Jordan, A., Lindinger, W., and Crutzen, P. J.: Acetone, methanol, and other partially oxidized volatile organic emissions from dead plant matter by abiological processes: Significance for atmospheric HO&lt;sub&gt;x&lt;/sub&gt; chemistry, Global Biogeochem. Cy., 13, 9–17, 1999. </mixed-citation>
</ref>
<ref id="ref64">
<label>64</label><mixed-citation publication-type="other" xlink:type="simple"> Wesely, M. L. and Hart, R. L.: Variability of short term eddy-covariance estimates of mass exchange, in: The forest atmosphere interactions, edited by: Hutchison, B. and Hicks, B., D Reidel publishing Company, Dortrecht, The Netherlands, 591–612, 1985 </mixed-citation>
</ref>
<ref id="ref65">
<label>65</label><mixed-citation publication-type="other" xlink:type="simple"> Wilkinson, M. J.: Circadian control of isoprene emissions from oil palm, Ph.D thesis, Lancaster University, 2006. </mixed-citation>
</ref>
<ref id="ref66">
<label>66</label><mixed-citation publication-type="other" xlink:type="simple"> UN ECE: Protocol to the 1979 Convention on Long-Range Transboundary Air Pollution Concerning the Control of Emissions of Volatile Organic Compounds on their Transboundary Fluxes, ECE/EB.AIR/30, United Nations Economic Commission for Europe, Geneva, Switzerland, 1991. </mixed-citation>
</ref>
<ref id="ref67">
<label>67</label><mixed-citation publication-type="other" xlink:type="simple"> UN ECE: Protocol to the 1979 Convention on Long-range Transboundary Air Pollution to Abate Acidification, Eutrophication and Ground-level Ozone, United Nations Economic Commission for Europe, Geneva, Switzerland, 1999. </mixed-citation>
</ref>
<ref id="ref68">
<label>68</label><mixed-citation publication-type="other" xlink:type="simple"> Zhao, J. and Zhang, R. Y.: Proton transfer reaction rate constants between hydronium ion (H&lt;sub&gt;3&lt;/sub&gt;O(+)) and volatile organic compounds, Atmos. Environ., 38, 2177–2185, 2004. </mixed-citation>
</ref>
</ref-list>
</back>
</article>