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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-7-4953-2007</article-id>
<title-group>
<article-title>Civil Aircraft for the regular investigation of the atmosphere based on an instrumented container: The new CARIBIC system</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Brenninkmeijer</surname>
<given-names>C. A. M.</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>Crutzen</surname>
<given-names>P.</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>Boumard</surname>
<given-names>F.</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>Dauer</surname>
<given-names>T.</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>Dix</surname>
<given-names>B.</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>Ebinghaus</surname>
<given-names>R.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Filippi</surname>
<given-names>D.</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>Fischer</surname>
<given-names>H.</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>Franke</surname>
<given-names>H.</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>Frieβ</surname>
<given-names>U.</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>Heintzenberg</surname>
<given-names>J.</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>Helleis</surname>
<given-names>F.</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>Hermann</surname>
<given-names>M.</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>Kock</surname>
<given-names>H. H.</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>Koeppel</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>Lelieveld</surname>
<given-names>J.</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>Leuenberger</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Martinsson</surname>
<given-names>B. G.</given-names>
</name>
<xref ref-type="aff" rid="aff10">
<sup>10</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Miemczyk</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Moret</surname>
<given-names>H. P.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Nguyen</surname>
<given-names>H. N.</given-names>
</name>
<xref ref-type="aff" rid="aff10">
<sup>10</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Nyfeler</surname>
<given-names>P.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Oram</surname>
<given-names>D.</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>O&apos;Sullivan</surname>
<given-names>D.</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Penkett</surname>
<given-names>S.</given-names>
</name>
<xref ref-type="aff" rid="aff12">
<sup>12</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Platt</surname>
<given-names>U.</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>Pupek</surname>
<given-names>M.</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>Ramonet</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>Randa</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>Reichelt</surname>
<given-names>M.</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>Rhee</surname>
<given-names>T. S.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff19">
<sup>19</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rohwer</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rosenfeld</surname>
<given-names>K.</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Scharffe</surname>
<given-names>D.</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>Schlager</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Schumann</surname>
<given-names>U.</given-names>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Slemr</surname>
<given-names>F.</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>Sprung</surname>
<given-names>D.</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>Stock</surname>
<given-names>P.</given-names>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Thaler</surname>
<given-names>R.</given-names>
</name>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Valentino</surname>
<given-names>F.</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>van Velthoven</surname>
<given-names>P.</given-names>
</name>
<xref ref-type="aff" rid="aff14">
<sup>14</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Waibel</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff15">
<sup>15</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wandel</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff16">
<sup>16</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Waschitschek</surname>
<given-names>K.</given-names>
</name>
<xref ref-type="aff" rid="aff17">
<sup>17</sup>
</xref>
<xref ref-type="aff" rid="aff20">
<sup>20</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wiedensohler</surname>
<given-names>A.</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>Xueref-Remy</surname>
<given-names>I.</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>Zahn</surname>
<given-names>A.</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>Zech</surname>
<given-names>U.</given-names>
</name>
<xref ref-type="aff" rid="aff18">
<sup>18</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ziereis</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff13">
<sup>13</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Max-Planck-Institut für Chemie (MPI), Air Chemistry Division, Joh.-J.-Becherweg 27, 55128 Mainz, Germany</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Lufthansa Technik, Lufthansa Base, Frankfurt Airport, FRA WE 24, 60546 Frankfurt, Germany</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Institut für Umweltphysik, Universität Heidelberg, INF229, 69120 Heidelberg, Germany</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>GKSS-Research Centre, Institute for Coastal Research (GKSS), Max-Planck-Str. 1, 21502 Geesthacht, Germany</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Laboratoire des Sciences du Climat et de l&apos;Environnement (CNRS), Unité mixte CNRS/CEA, CEA Saclay Orme des Merisiers &amp;ndash; Bat.703, Pièce 26, 91191 Gif sur Yvette Cedex, France</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Institut für Meteorologie und Klimaforschung (IMK), Forschungszentrum Karlsruhe, Weberstr. 5, 76133 Karlsruhe, Germany</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>Enviscope GmbH, Arnoldhainer Str. 5, 60489 Frankfurt, Germany</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>Leibniz-Institut für Troposphärenforschung (IFT), Permoserstr. 15, 04318 Leipzig, Germany</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>University Bern, Institut für Klima- und Umweltphysik, Sidlerstr. 5, 3012 Bern, Switzerland</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>University of Lund, Division of Nuclear Physics, P.O. Box 118, 22100 Lund, Sweden</addr-line>
</aff>
<aff id="aff11">
<label>11</label>
<addr-line>Lufthansa Technik, VIP &amp; Government Jet Maintenance, Weg beim Jaeger 193, 22335, Hamburg, Germany</addr-line>
</aff>
<aff id="aff12">
<label>12</label>
<addr-line>University of East Anglia, School of Environmental Sciences, Norwich, NR4 7TJ, UK</addr-line>
</aff>
<aff id="aff13">
<label>13</label>
<addr-line>Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, 82230 Wessling, Germany</addr-line>
</aff>
<aff id="aff14">
<label>14</label>
<addr-line>Royal Netherlands Meteorological Institute (KNMI), P.O. Box 201, NL-3730 AE, de Bilt, the Netherlands</addr-line>
</aff>
<aff id="aff15">
<label>15</label>
<addr-line>Lufthansa, Environmental Division, Frankfurt Airport Center, Hugo-Eckener-Ring B.649, 60549 Frankfurt, Germany</addr-line>
</aff>
<aff id="aff16">
<label>16</label>
<addr-line>Heggeman Aerospace AG, Zeppelinring 1&amp;ndash;6, 33142 Büren, Germany</addr-line>
</aff>
<aff id="aff17">
<label>17</label>
<addr-line>Garner CAD Technik GmbH, Argelsrieder Feld 2/4, 82234 Oberpfaffenhofen, Germany</addr-line>
</aff>
<aff id="aff18">
<label>18</label>
<addr-line>KOLT Engineering GmbH, Argelsrieder Feld 20, 82234 Oberpfaffenhofen, Germany</addr-line>
</aff>
<aff id="aff19">
<label>19</label>
<addr-line>now at: Korean Polar Research Institute, Sangrokgu Sa-2-dong 1270, Ansan 426-744, Korea</addr-line>
</aff>
<aff id="aff20">
<label>20</label>
<addr-line>now at: RUAG Aerospace Services GmbH, P.O.Box 1253, 82231 Wessling, Germany</addr-line>
</aff>
<pub-date pub-type="epub">
<day>27</day>
<month>09</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>18</issue>
<fpage>4953</fpage>
<lpage>4976</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/7/4953/2007/acp-7-4953-2007.html">This article is available from http://www.atmos-chem-phys.net/7/4953/2007/acp-7-4953-2007.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/4953/2007/acp-7-4953-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/4953/2007/acp-7-4953-2007.pdf</self-uri>
<abstract>
<p>An airfreight container with automated instruments for measurement of
atmospheric gases and trace compounds was operated on a monthly basis
onboard a Boeing 767-300 ER of LTU International Airways during
long-distance flights from 1997 to 2002 (CARIBIC, Civil Aircraft for Regular
Investigation of the Atmosphere Based on an Instrument Container,
&lt;a href=&quot;http://www.caribic-atmospheric.com&quot;&gt;http://www.caribic-atmospheric.com&lt;/a&gt;). Subsequently a more advanced system has
been developed, using a larger capacity container with additional equipment
and an improved inlet system. CARIBIC phase #2 was implemented on a new
long-range aircraft type Airbus A340-600 of the Lufthansa German Airlines
(Star Alliance) in December 2004, creating a powerful flying observatory.
The instrument package comprises detectors for the measurement of O&lt;sub&gt;3&lt;/sub&gt;,
total and gaseous H&lt;sub&gt;2&lt;/sub&gt;O, NO and NO&lt;sub&gt;y&lt;/sub&gt;, CO, CO&lt;sub&gt;2&lt;/sub&gt;, O&lt;sub&gt;2&lt;/sub&gt;, Hg, and
number concentrations of sub-micrometer particles (&amp;gt;4 nm, &amp;gt;12 nm, and
&amp;gt;18 nm diameter). Furthermore, an optical particle counter (OPC) and a
proton transfer mass spectrometer (PTR-MS) are incorporated. Aerosol samples
are collected for analysis of elemental composition and particle morphology
after flight. Air samples are taken in glass containers for laboratory
analyses of hydrocarbons, halocarbons and greenhouse gases (including
isotopic composition of CO&lt;sub&gt;2&lt;/sub&gt;) in several laboratories. Absorption tubes
collect oxygenated volatile organic compounds. Three differential optical
absorption spectrometers (DOAS) with their telescopes mounted in the inlet
system measure atmospheric trace gases such as BrO, HONO, and NO&lt;sub&gt;2&lt;/sub&gt;. A
video camera mounted in the inlet provides information about clouds along
the flight track. The flying observatory, its equipment and examples of
measurement results are reported.</p>
</abstract>
<counts><page-count count="24"/></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"> An, W. J., Pathak, R. K., Lee, B.-H., and Pandis, S. N.: Aerosol volatility measurements using an improved thermodenuder: Application to secondary organic aerosol, J. Aerosol Sci. 38, 305&amp;ndash;314, 2007. </mixed-citation>
</ref>
<ref id="ref2">
<label>2</label><mixed-citation publication-type="other" xlink:type="simple"> Bischof, W.: Carbon dioxide measurements from aircraft, Tellus, 22, 545&amp;ndash;549, 1970. </mixed-citation>
</ref>
<ref id="ref3">
<label>3</label><mixed-citation publication-type="other" xlink:type="simple"> Bozóki, Z., Sneider, J., Gingl, Z., Mohásci, A., Szakáll, M., Bor, Z., and Szabó, G.: A high-sensitivity, near-infrared tunable-diode-laser-based photoacoustic water-vapour-detection system for automated operation, Meas. Sci. Technol., 10, 999&amp;ndash;1003, 1999. </mixed-citation>
</ref>
<ref id="ref4">
<label>4</label><mixed-citation publication-type="other" xlink:type="simple"> Bozóki, Z., Szakáll, M., Mohásci, A., Szakáll, M., Szabó, G., and Bor, Z.: Diode laser based photoacoustic humidity sensors, Sens. Actuators, B 91, 219&amp;ndash;226, 2003. </mixed-citation>
</ref>
<ref id="ref5">
<label>5</label><mixed-citation publication-type="other" xlink:type="simple"> Brenninkmeijer, C. A. M., Crutzen, P. J., Fischer, H., Güsten, H., Hans, W., Heinrich, G., Heintzenberg, J., Hermann, M., Immelmann, T., Kersting, D., Maiss, M., Nolle, M., Pitscheider, A., Pohlkamp, H., Scharffe, D., Specht, K., and Wiedensohler, A.: CARIBIC &amp;ndash; civil aircraft for global measurement of trace gases and aerosols in the tropopause region, J. Atmos. Oceanic Technol., 16, 1373&amp;ndash;1383, 1999. </mixed-citation>
</ref>
<ref id="ref6">
<label>6</label><mixed-citation publication-type="other" xlink:type="simple"> Brough, N., Reeves, C., Penkett, S. A., Dewey, K., Kent, J., Barjat, H., Monks, P.S., Ziereis, H., Stock, P., Huntrieser, H., and Schlager, H.: Intercomparison of aircraft instruments on board the C-130 and Falcon 20 over southern Germany during EXPORT 2000, Atmos. Chem. Phys., 3, 2127&amp;ndash;2138, 2003. </mixed-citation>
</ref>
<ref id="ref7">
<label>7</label><mixed-citation publication-type="other" xlink:type="simple"> Brunner, D., Staehelin, J., Jeker, D., Wernli, H., and Schumann, U.: Nitrogen oxides and ozone in the tropopause region of the northern hemisphere: measurements from commercial aircraft in 1995/1996 and 1997, J. Geophys. Res., 106, 27 673&amp;ndash;27 699, 2001. </mixed-citation>
</ref>
<ref id="ref8">
<label>8</label><mixed-citation publication-type="other" xlink:type="simple"> Connors, V. S., Cahoon, D. R., Reichle, H. G., Jr., and Scheel, H. E.: Comparison between carbon monoxide measurements from spaceborne and airborne platforms, Can. J. Phys., 69, 1128&amp;ndash;1137, 1991. </mixed-citation>
</ref>
<ref id="ref9">
<label>9</label><mixed-citation publication-type="other" xlink:type="simple"> Crutzen, P. J., Elansky, N. F., Hahn, M., Golitsyn, G. S., Brenninkmeijer, C. A. M., Scharffe, D. H., Belikov, I. B., Maiss, M., Bergamaschi, P., Röckmann, T., Grisenko, A. M., and Sevostyanov, V. M.: Trace gas measurements between Moscow and Vladivostok using the Trans-Siberian railroad, J. Atmos. Chem. 29, 179&amp;ndash;194, 1998. </mixed-citation>
</ref>
<ref id="ref10">
<label>10</label><mixed-citation publication-type="other" xlink:type="simple"> De Gouw, J., Warneke, C., Holzinger, R., Klüpfel, T., and Williams, J.: Intercomparison between airborne measurements of methanol, acetonitrile and acetone using two differently configured PTR-MS instruments, Int. J. Mass Spectrometry, 239, 129&amp;ndash;137, 2004. </mixed-citation>
</ref>
<ref id="ref11">
<label>11</label><mixed-citation publication-type="other" xlink:type="simple"> Dickerson, R. R.: Measurements of reactive nitrogen compounds in the free troposphere, Atmos. Environ., 18, 2585&amp;ndash;2593, 1984. </mixed-citation>
</ref>
<ref id="ref12">
<label>12</label><mixed-citation publication-type="other" xlink:type="simple"> Ebinghaus, R. and Slemr, F.: Aircraft measurements of atmospheric mercury over southern and eastern Germany, Atmos. Environ., 34, 895&amp;ndash;903, 2000. </mixed-citation>
</ref>
<ref id="ref13">
<label>13</label><mixed-citation publication-type="other" xlink:type="simple"> Ebinghaus, R., Slemr, F., Brenninkmeijer, C. A. M., van Velthoven, P., Zahn, A., Hermann, M., Oram, D. E., and O&apos;Sullivan, D.: Emissions of gaseous mercury from biomass burning in South America in 2005 observed during CARIBIC flights, Geophys. Res. Lett., 34, doi:10.1029/2006GL028866, 2007. </mixed-citation>
</ref>
<ref id="ref14">
<label>14</label><mixed-citation publication-type="other" xlink:type="simple"> Fabian, P. and Pruchniewicz, P. G.: Meridional distribution of ozone in the troposphere and its seasonal variations, J. Geophys. Res., 82, 2063&amp;ndash;2073, 1977. </mixed-citation>
</ref>
<ref id="ref15">
<label>15</label><mixed-citation publication-type="other" xlink:type="simple"> Falconer, P. D. and Holdeman, J. D.: Measurements of atmospheric ozone made from a GASP-equipped 747 airliner: mid March, 1975, Geophys. Res. Lett., 3, 101&amp;ndash;104, 1976. </mixed-citation>
</ref>
<ref id="ref16">
<label>16</label><mixed-citation publication-type="other" xlink:type="simple"> Fitzenberger, R., Bösch, H., Camy-Peyret, C., Chipperfield, M., Harder, H., Platt, U., Sinnhuber, B.-M., Wagner, T., and Pfeilsticker, K.: First profile measurement of tropospheric BrO, Geophys. Res. Lett., 27, 2921&amp;ndash;2924, 2000. </mixed-citation>
</ref>
<ref id="ref17">
<label>17</label><mixed-citation publication-type="other" xlink:type="simple"> Foulger, B. E. and Simmonds, P. G.: Ambient temperature gas purifier suitable for the trace analysis of carbon monoxide and hydrogen and the preparation of low-level carbon monoxide calibration standards in the field, J. Chromatog., 630, 257&amp;ndash;263, 1993. </mixed-citation>
</ref>
<ref id="ref18">
<label>18</label><mixed-citation publication-type="other" xlink:type="simple"> Gerbig, C., Kley, D., Volz-Thomas, A., Kent, J., Dewey, K., and McKenna, D.S.: Fast-response resonance fluorescence CO measurements aboard the C-130: Instrument characterization and measurements made during NARE `93, J. Geophys. Res., 101, 29 229&amp;ndash;29 238, 1996. </mixed-citation>
</ref>
<ref id="ref19">
<label>19</label><mixed-citation publication-type="other" xlink:type="simple"> Gerbig, C., Schmitgen, S., Kley, D., Volz-Thomas, A., Dewey, K., and Haaks, D.: An improved fast-response vacuum-UV resonance fluorescence CO instrument, J. Geophys. Res., 104, 1699&amp;ndash;1704, 1999. </mixed-citation>
</ref>
<ref id="ref20">
<label>20</label><mixed-citation publication-type="other" xlink:type="simple"> Güsten, H., Heinrich, G., Schmidt, R. W. H., and Schurath, U.: A novel ozone sensor for direct eddy flux measurements, J. Atmos. Chem., 14, 73&amp;ndash;84, 1992. </mixed-citation>
</ref>
<ref id="ref21">
<label>21</label><mixed-citation publication-type="other" xlink:type="simple"> Hansel, A., Jordan, A., Warneke, C., Holzinger, R., Wisthaler, A., and Lindinger, W.: Proton-transfer-reaction mass spectrometry (PTR-MS): on-line monitoring of volatile organic compounds at volume mixing ratios of a few pptv, Plasma Sources Sci. Technol., 8, 332&amp;ndash;336, 1999. </mixed-citation>
</ref>
<ref id="ref22">
<label>22</label><mixed-citation publication-type="other" xlink:type="simple"> Heintzenberg, J., Hermann, M., Martinsson, B. G., and Papaspiropoulos, G.: Number and sulfur derived 3-parameter aerosol size distributions in the tropopause region from CARIBIC flights between Germany and the Indic, J. Aerosol Sci., 33, 595&amp;ndash;608, 2002. </mixed-citation>
</ref>
<ref id="ref23">
<label>23</label><mixed-citation publication-type="other" xlink:type="simple"> Heintzenberg, J., Hermann, M., and Theiss, D.: Out of Africa: High aerosol concentrations in the upper troposphere over Africa, Atmos. Chem. Phys., 3, 1191&amp;ndash;1198, 2003. </mixed-citation>
</ref>
<ref id="ref24">
<label>24</label><mixed-citation publication-type="other" xlink:type="simple"> Hermann, M., Stratmann, F., Wilck, M., and Wiedensohler, A.: Sampling characteristics of an aircraft-borne aerosol inlet system, J. Atmos. Oceanic Technol., 18, 7&amp;ndash;19, 2001. </mixed-citation>
</ref>
<ref id="ref25">
<label>25</label><mixed-citation publication-type="other" xlink:type="simple"> Hermann, M. and Wiedensohler, A.: Counting efficiency of condensation particle counters at low-pressures with illustrative data from the upper troposphere, J. Aerosol Sci., 32, 975&amp;ndash;99, 2001. </mixed-citation>
</ref>
<ref id="ref26">
<label>26</label><mixed-citation publication-type="other" xlink:type="simple"> Hermann, M., Heintzenberg, J., Wiedensohler, A., Zahn, A., Heinrich, G., and Brenninkmeijer, C.A.M.: Meridional distributions of aerosol particle number concentrations in the upper troposphere and lower stratosphere obtained by Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container (CARIBIC) flights. J. Geophys. Res., 108, No. D3, 4114-4130, doi:10.1029/2001JD001077, 2003. </mixed-citation>
</ref>
<ref id="ref27">
<label>27</label><mixed-citation publication-type="other" xlink:type="simple"> Heue, K.-P , Richter, A., Bruns, M., Burrows, J.P., von Friedeburg, C., Platt, U., Pundt, I., Wang, P., and Wagner, T.: Validation of SCIAMACHY tropospheric NO&lt;sub&gt;2&lt;/sub&gt; columns with AMAXDOAS measurements, Atmos. Chem. Phys., 5, 1039&amp;ndash;1051, 2005. </mixed-citation>
</ref>
<ref id="ref28">
<label>28</label><mixed-citation publication-type="other" xlink:type="simple"> Hurst, D. F., Romashkin, P. A., Elkins, J. W., Oberländer, E. A., Elansky, N. F., Belikov, I. B., Granberg, I. G., Golitsyn, G. S., Grisenko, A. M., Brenninkmeijer, C. A. M., and Crutzen, P. J.: Emissions of ozone-depleting substances in Russia during 2001, J. Geophys. Res., 109, D14, D14303, doi:10.1029/2004JD004633, 2004. </mixed-citation>
</ref>
<ref id="ref29">
<label>29</label><mixed-citation publication-type="other" xlink:type="simple"> Joeckel, P.: Cosmogenic $^14$CO as Tracer for Atmospheric Chemistry and Transport. Ph.D. Thesis, 347, University of Heidelberg, 2000. </mixed-citation>
</ref>
<ref id="ref30">
<label>30</label><mixed-citation publication-type="other" xlink:type="simple"> Krol, M. C., Lelieveld, J., Oram, D. E., Sturrock, G. A., Penkett, S. A., Brenninkmeijer, C. A. M., Gros, V., Williams, J., and Scheeren, H. A.: Continuing emissions of methylchloroform from Europe, Nature, 421, 131&amp;ndash;135, 2003. </mixed-citation>
</ref>
<ref id="ref31">
<label>31</label><mixed-citation publication-type="other" xlink:type="simple"> Lelieveld, J., van Aardenne, J., Fischer, H., de Reus, M., Williams, J., and Winkler, P.: Increasing ozone over the Atlantic Ocean, Science, 304, 1483&amp;ndash;1487, 2004. </mixed-citation>
</ref>
<ref id="ref32">
<label>32</label><mixed-citation publication-type="other" xlink:type="simple"> Lindinger, W., Hansel, A., and Jordan, A.: On-line monitoring of volatile organic compounds at ppt-levels by means of proton-transfer-reaction mass spectrometry (PTR-MS): Medical applications, food control and environmental research, Int. J. Mass Spectrom. Ion Processes, 173, 191&amp;ndash;241, 1998. </mixed-citation>
</ref>
<ref id="ref33">
<label>33</label><mixed-citation publication-type="other" xlink:type="simple"> Liu, B. Y. H., Zhang, Z. Q., and Kuehn, T. H.: A numerical study of inertial errors in anisokinetic sampling, J. Aerosol Sci., 20, 367&amp;ndash;380, 1989. </mixed-citation>
</ref>
<ref id="ref34">
<label>34</label><mixed-citation publication-type="other" xlink:type="simple"> Marenco, A., Thouret, V., Nédélec, P., Smit, H., Helten, M., Kley, D., Karcher, F., Simon, P., Law, K., Pyle, J., Poschmann, G., Von Wrede, R., Hume, C., and Cook, T.: Measurement of ozone and water vapor by Airbus in-service aircraft: The MOZAIC airborne program, an overview, J. Geophys. Res., 103, 25 631&amp;ndash;25 642, 1998. </mixed-citation>
</ref>
<ref id="ref35">
<label>35</label><mixed-citation publication-type="other" xlink:type="simple"> Martinsson, B. G., Frank, G., Cederfelt, S.-I., Berg, O. H., Mentes, B., Papaspiropoulos, G., Swietlicki, E., Zhou, J., Flynn, M., Bower, K. N., Choularton, T. W., Mäkelä, J., Virkkula, A., and van Dingenen, R.: Validation of very high cloud droplet number concentrations in air masses transported thousands of kilometers over the ocean, Tellus 52B, 801&amp;ndash;814, 2000. </mixed-citation>
</ref>
<ref id="ref36">
<label>36</label><mixed-citation publication-type="other" xlink:type="simple"> Martinsson, B. G., Papaspiropoulos, G., Heintzenberg, J., and Hermann, M.: Fine mode particulate sulphur in the tropopause region measured from intercontinental flights (CARIBIC), \mboxGeophys. Res. Lett., 28, 1175&amp;ndash;1178, 2001. </mixed-citation>
</ref>
<ref id="ref37">
<label>37</label><mixed-citation publication-type="other" xlink:type="simple"> Martinsson, B. G., Nguyen, H. N., Brenninkmeijer, C. A. M., Zahn, A., Heintzenberg, J., Hermann, M., and van Velthoven, P. F. J.: Characteristics and origin of lowermost stratospheric aerosol at northern midlatitudes under volcanically quiescent conditions based on CARIBIC observations, J. Geophys. Res., 110, D12201, doi:10.1029/2004JD005644, 2005. </mixed-citation>
</ref>
<ref id="ref38">
<label>38</label><mixed-citation publication-type="other" xlink:type="simple"> Matsueda, H. and Inoue, H. Y.: Measurements of atmospheric CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;4&lt;/sub&gt; using a commercial airliner from 1993 to 1994, Atmos. Environ., 30, 1647&amp;ndash;1655, 1996. </mixed-citation>
</ref>
<ref id="ref39">
<label>39</label><mixed-citation publication-type="other" xlink:type="simple"> Montzka, S. A. and Fraser, P. J.: Controlled substances and other source gases, in: Scientific Assessment of Ozone Depletion: 2002, Global Ozone Research and Monitoring Project, vol. 47, edited by: Ennis, C. A. , chap. 1, pp.1.1&amp;ndash;1.83, World Meteorol. Org., Geneva Switzerland, 2003. </mixed-citation>
</ref>
<ref id="ref40">
<label>40</label><mixed-citation publication-type="other" xlink:type="simple"> Mühle, J., Brenninkmeijer, C.A. M., Rhee, T. S., Slemr, F., Oram, D. E., Penkett, S. A., and Zahn, A.: Biomass burning and fossil fuel signatures in the upper troposphere observed during a CARIBIC flight from Namibia to Germany, Geophys. Res. Lett., 29, No.19, 1910, doi:10.1029/2002GL015764, 2002. </mixed-citation>
</ref>
<ref id="ref41">
<label>41</label><mixed-citation publication-type="other" xlink:type="simple"> Murphy, D. M. and Schein, M. E.: Wind tunnel tests of a shrouded aircraft inlet, Aerosol Sci. Technol. 28, 33&amp;ndash;39, 1998. </mixed-citation>
</ref>
<ref id="ref42">
<label>42</label><mixed-citation publication-type="other" xlink:type="simple"> Murphy, D. M., Cziczo, D. J., Hudson, P. K., Thomson, D. S., Wilson, J. C., Kojima, T., and Buseck, P. R.: Particle generation and resuspension in aircraft inlets when flying in clouds, Aerosol Sci. Technol. 38, 400&amp;ndash;408, 2004. </mixed-citation>
</ref>
<ref id="ref43">
<label>43</label><mixed-citation publication-type="other" xlink:type="simple"> Murphy, D. M., Cziczo, D. J., Froyd, K. D., Hudson, P. K., Matthew, B. M., Middlebrook, A. M., Peltier, R. E., Sullivan, A., Thomson, D. S., and Weber, R. J.: Single-particle mass spectrometry of tropospheric aerosol particles, J. Geophys. Res., 111, D23S32, doi:10.1029/2006JD007340, 2006. </mixed-citation>
</ref>
<ref id="ref44">
<label>44</label><mixed-citation publication-type="other" xlink:type="simple"> Nastrom, G. D.: Ozone in the upper troposphere from the GASP measurements, J. Geophys. Res., 84, 25 631&amp;ndash;25 642, 1979. </mixed-citation>
</ref>
<ref id="ref45">
<label>45</label><mixed-citation publication-type="other" xlink:type="simple"> Neuman, J. A., Huey, L. G., Ryerson, T. B., and Fahey, D. W.: Study of inlet materials for sampling atmospheric nitric acid, Environ. Sci. Technol. 33, 1133&amp;ndash;1136, 1999. </mixed-citation>
</ref>
<ref id="ref46">
<label>46</label><mixed-citation publication-type="other" xlink:type="simple"> Nguyen, H. N., Gudmundsson, A., and Martinsson, B. G.: Design and calibration of a multi-channel aerosol sampler for studies of the tropopause region from the CARIBIC platform, Aerosol Sci. Technol. 40, 649&amp;ndash;655, 2006. </mixed-citation>
</ref>
<ref id="ref47">
<label>47</label><mixed-citation publication-type="other" xlink:type="simple"> Nguyen, H. N. and Martinsson, B. G.: Analysis of C, N,and O in aerosol collected on an organic backing using internal blank measurements and variable beam size, Nuclear Instrum. Methods in Phys Res. B, in press, 2007. </mixed-citation>
</ref>
<ref id="ref48">
<label>48</label><mixed-citation publication-type="other" xlink:type="simple"> Papaspiropoulos G., Mentes, B., Kristiansson, P., and Martinsson, B. G.: A high sensitivity elemental analysis methodology for upper tropospheric aerosol, Nucl. Instr. Meth., B150, 356&amp;ndash;362, 1999. </mixed-citation>
</ref>
<ref id="ref49">
<label>49</label><mixed-citation publication-type="other" xlink:type="simple"> Papaspiropoulos, G., Martinsson, B. G., Zahn, A., Brenninkmeijer, C. A. M., Hermann, M., Heintzenberg, J., Fischer, H., and van Velthoven, P. F. J.: Aerosol elemental concentrations in the tropopause region from intercontinental flights with the CARIBIC platform, J. Geophys. Res., 107, D23, 4671, doi:10.1029/2002JD002344, 2002. </mixed-citation>
</ref>
<ref id="ref50">
<label>50</label><mixed-citation publication-type="other" xlink:type="simple"> Peylin, P., Bréon, F. M., Serrar, S., Tiwari, Y, Chédin, A., Gloor, M., Machida, T., Brenninkmeijer C.A.M. , Zahn A., and Ciais, P.: Evaluation of Television Infrared observation Satellite (TIROS-N) Operational Vertical Sounder (TOVS) spaceborne CO2 estimates using model simulations and aircraft data, J. Geophys. Res. 112, D09313, doi:10.1029/2005JD007018, 2007. </mixed-citation>
</ref>
<ref id="ref51">
<label>51</label><mixed-citation publication-type="other" xlink:type="simple"> Platt, U., Perner, D., and Pätz, H. W.: Simultaneous measurement of atmospheric CH&lt;sub&gt;2&lt;/sub&gt;O, O&lt;sub&gt;3&lt;/sub&gt;, and NO&lt;sub&gt;2&lt;/sub&gt; by differential optical absorption, J. Geophys. Res., 84, 6329&amp;ndash;6335, 1979. </mixed-citation>
</ref>
<ref id="ref52">
<label>52</label><mixed-citation publication-type="other" xlink:type="simple"> Platt, U.: Differential optical absorption spectroscopy (DOAS), in: Monitoring by Spectroscopic Techniques, edited by: Sigrist, M. W., John Wiley, New York, 1994. </mixed-citation>
</ref>
<ref id="ref53">
<label>53</label><mixed-citation publication-type="other" xlink:type="simple"> Pratt, R. and Falconer, P.: Circumpolar measurements of ozone, particles, and carbon monoxide from a commercial airliner, J. Geophys. Res., 84, 7876&amp;ndash;7882, 1979. </mixed-citation>
</ref>
<ref id="ref54">
<label>54</label><mixed-citation publication-type="other" xlink:type="simple"> Prinn, R. G., Weiss, R. F., Fraser, P. J., Simmonds, P. G., Cunnold, D. M., Alyea, F. N., O&apos;Doherty, S., Salameh, P., Miller, B. R., Huang, J., Wang, R. H. J., Hartley, D. E., Harth, C., Steele, L. P., Sturrock, G., Midgley, P. M., and McCulloch, A.: A history of chemically and radiatively important gases in air deduced from ALE/GAGE/AGAGE, J. Geophys. Res., 105, 17 751&amp;ndash;17 792, 2000. </mixed-citation>
</ref>
<ref id="ref55">
<label>55</label><mixed-citation publication-type="other" xlink:type="simple"> Pupek, M., Assonov, S. S., Mühle, J., Rhee, T. S., Oram, D., Koeppel, C., Slemr, F., and Brenninkmeijer, C. A. M.: Isotope analysis of hydrocarbons: Trapping, recovering and archiving hydrocarbons and halocarbons separated from ambient air, Rapid Commun. Mass Spectrometry, 19, 455&amp;ndash;460, 2005. </mixed-citation>
</ref>
<ref id="ref56">
<label>56</label><mixed-citation publication-type="other" xlink:type="simple"> Reichelt, M.: Entwicklung und atmosphärische Anwendung eines optischen Partikelzählers für Tropopausenbedingungen, Ph.D. thesis, University of Leipzig, 306, 2007. </mixed-citation>
</ref>
<ref id="ref57">
<label>57</label><mixed-citation publication-type="other" xlink:type="simple"> Rhee, T. S., Brenninkmeijer, C. A. M., and Röckmann, T.: The overwhelming role of soils in the global atmospheric hydrogen cycle, Atmos. Chem. Phys. 6, 1611&amp;ndash;1625, 2006. </mixed-citation>
</ref>
<ref id="ref58">
<label>58</label><mixed-citation publication-type="other" xlink:type="simple"> Schwarzenböck A., Heintzenberg, J., and Mertes, S.: Incorporation of aerosol particles between 25 and 850 nm into cloud elements: measurements with a new complementary sampling system, Atmos. Res. 52, 241&amp;ndash;260, 2000. </mixed-citation>
</ref>
<ref id="ref59">
<label>59</label><mixed-citation publication-type="other" xlink:type="simple"> Seiler, W. and Junge, C.: Decrease of carbon monoxide mixing ratio above the polar tropopause, Tellus, 21, 447&amp;ndash;449, 1969. </mixed-citation>
</ref>
<ref id="ref60">
<label>60</label><mixed-citation publication-type="other" xlink:type="simple"> Seiler, W. and Junge, C.: Carbon monoxide in the atmosphere, J. Geophys. Res., 75, 2217&amp;ndash;2226, 1970. </mixed-citation>
</ref>
<ref id="ref61">
<label>61</label><mixed-citation publication-type="other" xlink:type="simple"> Singh, H. B., Kanakidou, M., Crutzen, P. J., and Jacob; D. J.: High concentrations and photochemical fate of oxygenated hydrocarbons in the global troposphere, Nature 378, 50&amp;ndash;54, 1995. </mixed-citation>
</ref>
<ref id="ref62">
<label>62</label><mixed-citation publication-type="other" xlink:type="simple"> Singh, H. B., Salas, L. J., Chatfield, R. B., Czech, E., Fried, A., Walega, J., Evans, M. J., Field, B. D., Jacob, D. J., Blake, D., Heikes, B, Talbot, R., Sachse, G., Crawford, J. H., Avery, M. A., Sandholm, S., and Fuelberg, H.: Analysis of the atmospheric distribution, sources, and sinks of oxygenated volatile organic chemicals based on measurements over the Pacific during TRACE-P, J. Geophys. Res. 109, D15S07, doi:10.1029/2003JD003883, 2004. </mixed-citation>
</ref>
<ref id="ref63">
<label>63</label><mixed-citation publication-type="other" xlink:type="simple"> Slemr, F., Seiler, W., Eberling, C., and Roggendorf, P.: The determination of total gaseous mercury in air at background levels, Anal. Chim Acta, 110, 35&amp;ndash;47, 1979. </mixed-citation>
</ref>
<ref id="ref64">
<label>64</label><mixed-citation publication-type="other" xlink:type="simple"> Solomon, S. A., Schmeltekopf, A. L., and Sanders, R. W.: On the interpretation of zenith sky absorption measurements, J. Geophys. Res., 92, 8311&amp;ndash;8319, 1987. </mixed-citation>
</ref>
<ref id="ref65">
<label>65</label><mixed-citation publication-type="other" xlink:type="simple"> Stanier, C. O., Pathak, R. K., and Pandis, S. N.: Measurements of the volatility of aerosols from a-pinene ozonolysis, Environ. Sci. Technol. 41, 2756&amp;ndash;2763, 2007. </mixed-citation>
</ref>
<ref id="ref66">
<label>66</label><mixed-citation publication-type="other" xlink:type="simple"> Sturges, W. T., Oram, D. E., Carpenter, L. J., Penkett, S. A., and Engel, A.: Bromoform as a source of stratospheric bromine, Geophys. Res. Lett., 27, 2081&amp;ndash;2084, 2000. </mixed-citation>
</ref>
<ref id="ref67">
<label>67</label><mixed-citation publication-type="other" xlink:type="simple"> Szakáll, M., Bozóki, Z., Kraemer, M., Spelten, N., Möhler, O., and Schurath, U.: Evaluation of a photoacoustic detector for water vapor measurements under simulated tropospheric/lower stratospheric conditions, Environ. Sci. Technol., 35, 4881&amp;ndash;4885, 2001. </mixed-citation>
</ref>
<ref id="ref68">
<label>68</label><mixed-citation publication-type="other" xlink:type="simple"> Temme, C., Einax, J.W., Ebinghaus, R., and Schroeder, W.H.: Measurements of atmospheric mercury species at a coastal site in the Antarctic and over the South Atlantic Ocean during polar summer, Environ. Sci. Technol., 37, 22&amp;ndash;31, 2003. </mixed-citation>
</ref>
<ref id="ref69">
<label>69</label><mixed-citation publication-type="other" xlink:type="simple"> Tiefenau, H. K., Pruchniewicz, P. G., and Fabian, P.: Meridional distribution of tropospheric ozone from measurements aboard commercial airlines, Pure Appl. Geophys., 106&amp;ndash;108, 1036&amp;ndash;1040, 1973. </mixed-citation>
</ref>
<ref id="ref70">
<label>70</label><mixed-citation publication-type="other" xlink:type="simple"> Volz, A. and Kley, D.: A resonance fluorescence instrument for the in-situ measurement of atmospheric carbon monoxide, J. Atmos. Chem., 2, 345&amp;ndash;357, 1985. </mixed-citation>
</ref>
<ref id="ref71">
<label>71</label><mixed-citation publication-type="other" xlink:type="simple"> Volz-Thomas, A., Berg, M., Houben, N., Petrick, W., Raak, D., and Pätz, H.-W.: Measurements of total odd nitrogen (NO$_y)$ aboard MOZAIC in-service aircraft: instrument design, operation and performance, Atmos. Chem. Phys. 5, 583&amp;ndash;595, 2005. </mixed-citation>
</ref>
<ref id="ref72">
<label>72</label><mixed-citation publication-type="other" xlink:type="simple"> Wilson, K.L. and Birks, J.W.: Mechanism and elimination of a water vapor interference in the measurement of ozone by uv absorbance, Environ. Sci. Technol., 40, 6361&amp;ndash;6367, 2006. </mixed-citation>
</ref>
<ref id="ref73">
<label>73</label><mixed-citation publication-type="other" xlink:type="simple"> WMO (World Meteorological Organization):The Changing Atmosphere: An Integrated Global Atmospheric Chemistry Observation Theme for the IGOC Partnership, WMO/ GAW report No. 159 (WMO TD No. 1235), Geneva, Switzerland, 2004. </mixed-citation>
</ref>
<ref id="ref74">
<label>74</label><mixed-citation publication-type="other" xlink:type="simple"> Zahn, A, Brenninkmeijer, C. A. M., Maiss, M., Scharffe, D. H., Crutzen, P. J., Hermann, M., Wiedensohler, A., Heintzenberg, J., Güsten, H., Heinrich, G., Fischer, H., Cuijpers, J. W. M., and van Velthoven, P. F. J.: Identification of extratropical two-way troposphere-stratosphere mixing based on CARIBIC measurements of O&lt;sub&gt;3&lt;/sub&gt;, CO, and ultrafine particles, J. Geophys. Res., 105, 1527&amp;ndash;1535, 2000. </mixed-citation>
</ref>
<ref id="ref75">
<label>75</label><mixed-citation publication-type="other" xlink:type="simple"> Zahn, A., Brenninkmeijer, C. A. M., Asman, W. A. H., Crutzen, P. J., Heinrich, G., Fischer, H., Cuijpers, J. W. M., and van Velthoven, P. F. J.: The budgets of O&lt;sub&gt;3&lt;/sub&gt; and CO in the upper troposphere: CARIBIC passenger aircraft results 1997&amp;ndash;2001, J. Geophys. Res., 107, D17, 4337, doi:10.1029/2001JD001529, 2002a. </mixed-citation>
</ref>
<ref id="ref76">
<label>76</label><mixed-citation publication-type="other" xlink:type="simple"> Zahn, A., Brenninkmeijer, C. A. M., Crutzen, P. J., Parrish, D. D., Sueper, D., Heinrich, G., Güsten, H., Fischer, H., Hermann, M., and Heintzenberg, J.: Electrical discharge source for tropospheric &quot;ozone-rich transients&quot;, J. Geophys. Res., 107, D22, 4638, doi:10.1029/2002JD002345, 2002b. </mixed-citation>
</ref>
<ref id="ref77">
<label>77</label><mixed-citation publication-type="other" xlink:type="simple"> Zahn, A. and Brenninkmeijer, C. A. M.: New directions: a chemical tropopause defined, Atmos. Environ., 37, 439&amp;ndash;440, 2003. </mixed-citation>
</ref>
<ref id="ref78">
<label>78</label><mixed-citation publication-type="other" xlink:type="simple"> Zahn, A., Brenninkmeijer, C. A. M., and van Velthoven, P. F. J.: Passenger aircraft project CARIBIC 1997&amp;ndash;2002, Part I: The extratropical chemical tropopause, Atmos. Chem. Phys. Discuss., 4, 1091&amp;ndash;1117, 2004a. </mixed-citation>
</ref>
<ref id="ref79">
<label>79</label><mixed-citation publication-type="other" xlink:type="simple"> Zahn, A., Brenninkmeijer, C. A. M., and van Velthoven, P. F. J.: Passenger aircraft project CARIBIC 1997-2002, Part II: The ventilation of the lowermost stratosphere, Atmos. Chem. Phys. Discuss., 4, 1119&amp;ndash;1150, 2004b. </mixed-citation>
</ref>
<ref id="ref80">
<label>80</label><mixed-citation publication-type="other" xlink:type="simple"> Ziereis, H., Schlager, H., and Schulte, P.: NO, NO&lt;sub&gt;y&lt;/sub&gt;, and O&lt;sub&gt;3&lt;/sub&gt; intercomparisons during POLINAT 2, in: Pollution from Aircraft Emissions in the North Atlantic Flight Corridor (POLINAT 2), Air. Pollut. Res. Rep. 68, edited by: U. Schumann, pp. 55&amp;ndash;63, Eur. Comm., Luxembourg., 1999. </mixed-citation>
</ref>
<ref id="ref81">
<label>81</label><mixed-citation publication-type="other" xlink:type="simple"> Ziereis, H., Schlager, H., Schulte, P., van Velthoven, P. F. J., and Slemr, F.: Distributions of NO, NO&lt;sub&gt;x&lt;/sub&gt;, and NO&lt;sub&gt;y&lt;/sub&gt; in the upper troposphere and lower stratosphere between 28&amp;deg; and 61&amp;deg; N during POLINAT 2, J. Geophys. Res., 105, 3653&amp;ndash;3664, 2000. </mixed-citation>
</ref>
</ref-list>
</back>
</article>