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<front>
<journal-meta>
<journal-id journal-id-type="publisher">GMD</journal-id>
<journal-title-group>
<journal-title>Geoscientific Model Development</journal-title>
<abbrev-journal-title abbrev-type="publisher">GMD</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Geosci. Model Dev.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1991-9603</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/gmd-4-1133-2011</article-id>
<title-group>
<article-title>Improved convergence and stability properties in a three-dimensional higher-order ice sheet model</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Fürst</surname>
<given-names>J. 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>Rybak</surname>
<given-names>O.</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>Goelzer</surname>
<given-names>H.</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>De Smedt</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>de Groen</surname>
<given-names>P.</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>Huybrechts</surname>
<given-names>P.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Earth System Sciences &amp; Department of Geography, Vrije Universiteit Brussel, Pleinlaan 2, Brussels, Belgium</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Mathematics, Vrije Universiteit Brussel, Pleinlaan 2, Brussels, Belgium</addr-line>
</aff>
<pub-date pub-type="epub">
<day>19</day>
<month>12</month>
<year>2011</year>
</pub-date>
<volume>4</volume>
<issue>4</issue>
<fpage>1133</fpage>
<lpage>1149</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2011 J. J. Fürst et al.</copyright-statement>
<copyright-year>2011</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://gmd.copernicus.org/articles/4/1133/2011/gmd-4-1133-2011.html">This article is available from https://gmd.copernicus.org/articles/4/1133/2011/gmd-4-1133-2011.html</self-uri>
<self-uri xlink:href="https://gmd.copernicus.org/articles/4/1133/2011/gmd-4-1133-2011.pdf">The full text article is available as a PDF file from https://gmd.copernicus.org/articles/4/1133/2011/gmd-4-1133-2011.pdf</self-uri>
<abstract>
<p>We present a finite difference implementation of a three-dimensional
higher-order ice sheet model. In comparison to a conventional centred
difference discretisation it enhances both numerical stability and
convergence. In order to achieve these benefits the discretisation of the
governing force balance equation makes extensive use of information on
staggered grid points. Using the same iterative solver, a centred difference
discretisation that operates exclusively on the regular grid serves as a
reference. The reprise of the ISMIP-HOM experiments indicates that both
discretisations are capable of reproducing the higher-order model
inter-comparison results. This setup allows a direct comparison of the two
numerical implementations also with respect to their convergence behaviour.
First and foremost, the new finite difference scheme facilitates convergence
by a factor of up to 7 and 2.6 in average. In addition to this decrease in
computational costs, the accuracy for the resultant velocity field can be
chosen higher in the novel finite difference implementation. Changing the
discretisation also prevents build-up of local field irregularites that
occasionally cause divergence of the solution for the reference
discretisation.
&lt;br&gt;&lt;br&gt;
The improved behaviour makes the new discretisation more reliable for
extensive application to real ice geometries. Higher accuracy and robust
numerics are crucial in time dependent applications since numerical
oscillations in the velocity field of subsequent time steps are attenuated
and divergence of the solution is prevented.</p>
</abstract>
<counts><page-count count="17"/></counts>
</article-meta>
</front>
<body/>
<back>
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