Grid refinement in ICON v2.6.4
<p>This article describes the implementation of grid refinement in the ICOsahedral Nonhydrostatic (ICON) modeling system. It basically follows the classical two-way nesting approach known from widely used mesoscale models like MM5 or WRF, but it differs in the way feedback from fine grids to c...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2022-09-01
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| Series: | Geoscientific Model Development |
| Online Access: | https://gmd.copernicus.org/articles/15/7153/2022/gmd-15-7153-2022.pdf |
| _version_ | 1811208857543770112 |
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| author | G. Zängl D. Reinert F. Prill |
| author_facet | G. Zängl D. Reinert F. Prill |
| author_sort | G. Zängl |
| collection | DOAJ |
| description | <p>This article describes the implementation of grid refinement in the ICOsahedral Nonhydrostatic (ICON) modeling system.
It basically follows the classical two-way nesting approach known from widely used mesoscale models like MM5
or WRF, but it differs in the way feedback from fine grids to coarser grids is applied.
Moreover, the ICON implementation supports vertical nesting in the sense that the upper boundary of a nested domain
may be lower than that of its parent domain. Compared to the well-established implementations on quadrilateral grids,
new methods had to be developed for interpolating the lateral boundary conditions from the parent domain to the
child domain(s). These are based on radial basis functions (RBFs) and partly apply direct reconstruction of the
prognostic variables at the required grid points, whereas gradient-based extrapolation from parent to child grid
points is used in other cases.
The runtime flow control is written such that limited-area domains can be processed identically to nested domains
except for the lateral boundary data supply. To demonstrate the functionality and quality of the grid nesting in ICON,
idealized tests based on the Jablonowski–Williamson test case <span class="cit" id="xref_paren.1">(<a href="#bib1.bibx18">Jablonowski and Williamson</a>, <a href="#bib1.bibx18">2006</a>)</span> and the Schär mountain wave
test case <span class="cit" id="xref_paren.2">(<a href="#bib1.bibx28">Schär et al.</a>, <a href="#bib1.bibx28">2002</a>)</span> are presented. The results show that the numerical disturbances induced at the nest
boundaries are small enough to be negligible for real applications. This is confirmed by experiments closely
following the configuration used for operational numerical weather prediction at DWD, which demonstrate that a
regional refinement over Europe has a significant positive impact on the forecast quality in the Northern
Hemisphere.</p> |
| first_indexed | 2024-04-12T04:29:53Z |
| format | Article |
| id | doaj.art-5265e7de4bbd4a5383ae7fa3c7f6181a |
| institution | Directory Open Access Journal |
| issn | 1991-959X 1991-9603 |
| language | English |
| last_indexed | 2024-04-12T04:29:53Z |
| publishDate | 2022-09-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Geoscientific Model Development |
| spelling | doaj.art-5265e7de4bbd4a5383ae7fa3c7f6181a2022-12-22T03:47:58ZengCopernicus PublicationsGeoscientific Model Development1991-959X1991-96032022-09-01157153717610.5194/gmd-15-7153-2022Grid refinement in ICON v2.6.4G. ZänglD. ReinertF. Prill<p>This article describes the implementation of grid refinement in the ICOsahedral Nonhydrostatic (ICON) modeling system. It basically follows the classical two-way nesting approach known from widely used mesoscale models like MM5 or WRF, but it differs in the way feedback from fine grids to coarser grids is applied. Moreover, the ICON implementation supports vertical nesting in the sense that the upper boundary of a nested domain may be lower than that of its parent domain. Compared to the well-established implementations on quadrilateral grids, new methods had to be developed for interpolating the lateral boundary conditions from the parent domain to the child domain(s). These are based on radial basis functions (RBFs) and partly apply direct reconstruction of the prognostic variables at the required grid points, whereas gradient-based extrapolation from parent to child grid points is used in other cases. The runtime flow control is written such that limited-area domains can be processed identically to nested domains except for the lateral boundary data supply. To demonstrate the functionality and quality of the grid nesting in ICON, idealized tests based on the Jablonowski–Williamson test case <span class="cit" id="xref_paren.1">(<a href="#bib1.bibx18">Jablonowski and Williamson</a>, <a href="#bib1.bibx18">2006</a>)</span> and the Schär mountain wave test case <span class="cit" id="xref_paren.2">(<a href="#bib1.bibx28">Schär et al.</a>, <a href="#bib1.bibx28">2002</a>)</span> are presented. The results show that the numerical disturbances induced at the nest boundaries are small enough to be negligible for real applications. This is confirmed by experiments closely following the configuration used for operational numerical weather prediction at DWD, which demonstrate that a regional refinement over Europe has a significant positive impact on the forecast quality in the Northern Hemisphere.</p>https://gmd.copernicus.org/articles/15/7153/2022/gmd-15-7153-2022.pdf |
| spellingShingle | G. Zängl D. Reinert F. Prill Grid refinement in ICON v2.6.4 Geoscientific Model Development |
| title | Grid refinement in ICON v2.6.4 |
| title_full | Grid refinement in ICON v2.6.4 |
| title_fullStr | Grid refinement in ICON v2.6.4 |
| title_full_unstemmed | Grid refinement in ICON v2.6.4 |
| title_short | Grid refinement in ICON v2.6.4 |
| title_sort | grid refinement in icon v2 6 4 |
| url | https://gmd.copernicus.org/articles/15/7153/2022/gmd-15-7153-2022.pdf |
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