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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACPD</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACPD</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7375</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/acpd-9-26095-2009</article-id>
<title-group>
<article-title>A multi-model analysis of vertical ozone profiles</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Jonson</surname>
<given-names>J. E.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Stohl</surname>
<given-names>A.</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>Fiore</surname>
<given-names>A. M.</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>Hess</surname>
<given-names>P.</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>Szopa</surname>
<given-names>S.</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>Wild</surname>
<given-names>O.</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>Zeng</surname>
<given-names>G.</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</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>Dentener</surname>
<given-names>F. 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>Lupu</surname>
<given-names>A.</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>Schultz</surname>
<given-names>M. 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>Duncan</surname>
<given-names>B. N.</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>Sudo</surname>
<given-names>K.</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>Wind</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>Schulz</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>Marmer</surname>
<given-names>E.</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>Cuvelier</surname>
<given-names>C.</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>Keating</surname>
<given-names>T.</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>Zuber</surname>
<given-names>A.</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>Valdebenito</surname>
<given-names>A.</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>Dorokhov</surname>
<given-names>V.</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>De Backer</surname>
<given-names>H.</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>Davies</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff17">
<sup>17</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Chen</surname>
<given-names>G. H.</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>Johnson</surname>
<given-names>B.</given-names>
</name>
<xref ref-type="aff" rid="aff19">
<sup>19</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Tarasick</surname>
<given-names>D. W.</given-names>
</name>
<xref ref-type="aff" rid="aff17">
<sup>17</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Norwegian Meteorological Institute, Oslo, Norway</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>NILU, Kjeller, Norway</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Geophysical Fluid Dynamics Laboratory, NOAA, Princeton, NJ, USA</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>National Center for Atmospheric Research, Boulder, CO, USA</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>Laboratoire des Sciences du Climat et de l&apos;Environnement, CEA/CNRS/UVSQ/IPSL, Gif-sur-Yvette, France</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>Lancaster Environment Centre, Lancaster University, Lancaster, UK</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>Centre for Atmospheric Science, University of Cambridge, Cambridge, UK</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>European Commission, DG-Joint Research Centre, Institute for Environment and Sustainability, Ispra, Italy</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>Center for research in Earth and Space Science, York University, York, Canada</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>ICG-2, Forchungszentrum-Jülich, Jülich, Germany</addr-line>
</aff>
<aff id="aff11">
<label>11</label>
<addr-line>NASA Goddard Space Flight Center, Baltimore, MD, USA</addr-line>
</aff>
<aff id="aff12">
<label>12</label>
<addr-line>Grad. School of Environ. Studies, Nagoya University, Nagoya, Japan</addr-line>
</aff>
<aff id="aff13">
<label>13</label>
<addr-line>Office of Policy Analysis and Review, Environmental Protection Agency, Washington DC, USA</addr-line>
</aff>
<aff id="aff14">
<label>14</label>
<addr-line>Environment Directorate General, European Commission, Brussels, Belgium</addr-line>
</aff>
<aff id="aff15">
<label>15</label>
<addr-line>Central Aerological Observatory, Moscow, Russia</addr-line>
</aff>
<aff id="aff16">
<label>16</label>
<addr-line>Royal Meteorological Institute of Belgium (R. M. I. B.), Brussels, Belgium</addr-line>
</aff>
<aff id="aff17">
<label>17</label>
<addr-line>Environmental Canada, Downsview, Canada</addr-line>
</aff>
<aff id="aff18">
<label>18</label>
<addr-line>Central Weather Bureau, Taipei, Taiwan</addr-line>
</aff>
<aff id="aff19">
<label>19</label>
<addr-line>NOAA/ESRL, Boulder, CO, USA</addr-line>
</aff>
<aff id="aff20">
<label>20</label>
<addr-line>now at: National Institute of Water and Atmospheric Research, Lauder, New Zealand</addr-line>
</aff>
<pub-date pub-type="epub">
<day>08</day>
<month>12</month>
<year>2009</year>
</pub-date>
<volume>9</volume>
<issue>6</issue>
<fpage>26095</fpage>
<lpage>26142</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-discuss.net/9/26095/2009/acpd-9-26095-2009.html">This article is available from http://www.atmos-chem-phys-discuss.net/9/26095/2009/acpd-9-26095-2009.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/9/26095/2009/acpd-9-26095-2009.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/9/26095/2009/acpd-9-26095-2009.pdf</self-uri>
<abstract>
<p>A multi-model study of the long-range transport of ozone and its precursors
from major anthropogenic source regions was coordinated by the Task Force
on Hemispheric Transport of Air Pollution (TF HTAP) under the Convention
on Long-range Transboundary Air Pollution (LRTAP). Vertical profiles of
ozone at 12-h intervals in year 2001 are available from twelve of the
models contributing to this study and are compared here with observed
profiles from ozonesondes. The contributions from each major source
region are analysed for selected sondes, and this analysis is supplemented
by retroplume calculations using the FLEXPART Lagrangian particle dispersion
model to provide insight into the origin of ozone transport events and
the cause of differences between the models and observations.
&lt;br&gt;&lt;br&gt;
In the boundary layer ozone levels are in general strongly affected by
regional sources and sinks. With a considerably longer lifetime in the free
troposphere, ozone here is to a much larger extent affected by processes on a
larger scale such as intercontinental transport and exchange with the
stratosphere. Such individual events are difficult to trace over several days
or weeks of transport. As a result statistical relationships between models
and ozone sonde measurements are far less satisfactory than for surface
measurements at all seasons.
The lowest bias  between model
calculated ozone profiles and the ozone sonde measurements is seen in
the winter and autumn months. Following the increase in
photochemical activity in the spring and summer months the spread in model
results increases and the agreement between ozone sonde measurements and the
individual models deteriorates further.
&lt;br&gt;&lt;br&gt;
At selected sites calculated
contributions to ozone levels in the free troposphere from intercontinental
transport are presented. Intercontinental transport is identified based on
differences in model calculations with unperturbed emissions and emissions
reduced by 20% by region. With emissions perturbed by 20% per region
calculated intercontinental contributions to ozone in the free troposphere
range from less than 1 ppb to 3 ppb, with small contributions in winter.
The results are corroborated by the retroplume
calculations. At several locations the seasonal contributions to ozone in the
free troposphere from intercontinental transport differ from what has been
shown earlier at the surface using the same dataset. The large spread in
model results points to a need of further evaluation of the chemical
and physical processes in order to improve the credibility of global model
results.</p>
</abstract>
<counts><page-count count="48"/></counts>
</article-meta>
</front>
<body/>
<back>
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