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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-7-1773-2007</article-id>
<title-group>
<article-title>The Assimilation of Envisat data (ASSET) project</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Lahoz</surname>
<given-names>W. 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>Geer</surname>
<given-names>A. J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff16">
<sup>16</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Bekki</surname>
<given-names>S.</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>Bormann</surname>
<given-names>N.</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>Ceccherini</surname>
<given-names>S.</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>Elbern</surname>
<given-names>H.</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>Errera</surname>
<given-names>Q.</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>Eskes</surname>
<given-names>H. J.</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>Fonteyn</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>Jackson</surname>
<given-names>D. R.</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>Khattatov</surname>
<given-names>B.</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>Marchand</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>Massart</surname>
<given-names>S.</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>Peuch</surname>
<given-names>V.-H.</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>Rharmili</surname>
<given-names>S.</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>Ridolfi</surname>
<given-names>M.</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>Segers</surname>
<given-names>A.</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>Talagrand</surname>
<given-names>O.</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>Thornton</surname>
<given-names>H. 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>Vik</surname>
<given-names>A. F.</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>von Clarmann</surname>
<given-names>T.</given-names>
</name>
<xref ref-type="aff" rid="aff15">
<sup>15</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Data Assimilation Research Centre, University of Reading, Reading, UK</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Service Aeronomie, Universite Pierre et Marie Curie, Paris, France</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>ECMWF, Reading, UK</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>CNR-IFAC, Florence, Italy</addr-line>
</aff>
<aff id="aff5">
<label>5</label>
<addr-line>RIU, University of Köln, Köln, Germany</addr-line>
</aff>
<aff id="aff6">
<label>6</label>
<addr-line>BIRA-IASB, Brussels, Belgium</addr-line>
</aff>
<aff id="aff7">
<label>7</label>
<addr-line>KNMI, De Bilt, The Netherlands</addr-line>
</aff>
<aff id="aff8">
<label>8</label>
<addr-line>Met Office, Exeter, UK</addr-line>
</aff>
<aff id="aff9">
<label>9</label>
<addr-line>Fusion Numerics, Boulder, CO, USA</addr-line>
</aff>
<aff id="aff10">
<label>10</label>
<addr-line>CERFACS, Toulouse, France</addr-line>
</aff>
<aff id="aff11">
<label>11</label>
<addr-line>Météo-France, Toulouse, France</addr-line>
</aff>
<aff id="aff12">
<label>12</label>
<addr-line>University of Bologna, Bologna, Italy</addr-line>
</aff>
<aff id="aff13">
<label>13</label>
<addr-line>LMD, Paris, France</addr-line>
</aff>
<aff id="aff14">
<label>14</label>
<addr-line>NILU, Kjeller, Norway</addr-line>
</aff>
<aff id="aff15">
<label>15</label>
<addr-line>Forschungszentrum Karlsruhe, IMK, Germany</addr-line>
</aff>
<aff id="aff16">
<label>16</label>
<addr-line>now at: ECMWF,  Reading, UK</addr-line>
</aff>
<pub-date pub-type="epub">
<day>11</day>
<month>04</month>
<year>2007</year>
</pub-date>
<volume>7</volume>
<issue>7</issue>
<fpage>1773</fpage>
<lpage>1796</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/7/1773/2007/acp-7-1773-2007.html">This article is available from http://www.atmos-chem-phys.net/7/1773/2007/acp-7-1773-2007.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/7/1773/2007/acp-7-1773-2007.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/1773/2007/acp-7-1773-2007.pdf</self-uri>
<abstract>
<p>This paper discusses the highlights of the EU-funded &quot;Assimilation of
Envisat data&quot; (ASSET) project, which has involved assimilation of Envisat
atmospheric constituent and temperature data into systems based on Numerical
Weather Prediction (NWP) models and chemical transport models (CTMs).
Envisat was launched in 2002 and is one of the largest Earth Observation
(EO) satellites ever built. It carries several sophisticated EO instruments
providing insights into chemistry and dynamics of the atmosphere. In this paper
we focus on the assimilation of temperature and constituents from Envisat.

&lt;br&gt;&lt;br&gt;

The overarching theme of the ASSET project has been to bring together experts
from all aspects of the data assimilation problem. This has allowed ASSET to
address several themes comprehensively: enhancement of NWP analyses by
assimilation of research satellite data; studies of the distribution of
stratospheric chemical species by assimilation of research satellite data
into CTM systems; objective assessment of the quality of ozone analyses;
studies of the spatial and temporal evolution of tropospheric pollutants;
enhanced retrievals of Envisat data; and data archival and dissemination.

&lt;br&gt;&lt;br&gt;

Among the results from the ASSET project, many of which are firsts in their
field, we can mention: a positive impact on NWP analyses from assimilation
of height-resolved stratospheric humidity and temperature data, and
assimilation of limb radiances; the extraction of temperature information
from the assimilation of chemical species into CTMs; a first intercomparison
between ozone assimilation systems; the extraction of information on
tropospheric pollution from assimilation of Envisat data; and the large
potential of the Envisat MIPAS dataset. This paper discusses these, often
novel, developments and results. Finally, achievements of, and
recommendations from, the ASSET project are presented.</p>
</abstract>
<counts><page-count count="24"/></counts>
</article-meta>
</front>
<body/>
<back>
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