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<front>
<journal-meta>
<journal-id journal-id-type="publisher">OS</journal-id>
<journal-title-group>
<journal-title>Ocean Science</journal-title>
<abbrev-journal-title abbrev-type="publisher">OS</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Ocean Sci.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1812-0792</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/os-3-321-2007</article-id>
<title-group>
<article-title>On the assimilation of ice velocity and concentration data into large-scale sea ice models</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Dulière</surname>
<given-names>V.</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>Fichefet</surname>
<given-names>T.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Université Catholique de Louvain, Institut d&apos;Astronomie et de Géophysique Georges Lema&amp;icirc;tre, Louvain-la-Neuve, Belgium</addr-line>
</aff>
<pub-date pub-type="epub">
<day>08</day>
<month>06</month>
<year>2007</year>
</pub-date>
<volume>3</volume>
<issue>2</issue>
<fpage>321</fpage>
<lpage>335</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2007 V. Dulière</copyright-statement>
<copyright-year>2007</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by-nc-sa/2.5/">https://creativecommons.org/licenses/by-nc-sa/2.5/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://os.copernicus.org/articles/3/321/2007/os-3-321-2007.html">This article is available from https://os.copernicus.org/articles/3/321/2007/os-3-321-2007.html</self-uri>
<self-uri xlink:href="https://os.copernicus.org/articles/3/321/2007/os-3-321-2007.pdf">The full text article is available as a PDF file from https://os.copernicus.org/articles/3/321/2007/os-3-321-2007.pdf</self-uri>
<abstract>
<p>Data assimilation into sea ice models designed for climate studies has
started about 15 years ago. In most of the studies conducted so far, it is
assumed that the improvement brought by the assimilation is straightforward.
However, some studies suggest this might not be true. In order to elucidate
this question and to find an appropriate way to further assimilate sea ice
concentration and velocity observations into a global sea ice-ocean model, we
analyze here results from a number of twin experiments (i.e. experiments in
which the assimilated data are model outputs) carried out with a simplified
model of the Arctic sea ice pack. Our objective is to determine to what
degree the assimilation of ice velocity and/or concentration data improves
the global performance of the model and, more specifically, reduces the error
in the computed ice thickness. A simple optimal interpolation scheme is used,
and outputs from a control run and from perturbed experiments without and
with data assimilation are thoroughly compared. Our results indicate that,
under certain conditions depending on the assimilation weights and the type
of model error, the assimilation of ice velocity data enhances the model
performance. The assimilation of ice concentration data can also help in
improving the model behavior, but it has to be handled with care because of
the strong connection between ice concentration and ice thickness. This study
is first step towards real data assimilation into NEMO-LIM, a global sea
ice-ocean model.</p>
</abstract>
<counts><page-count count="15"/></counts>
</article-meta>
</front>
<body/>
<back>
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