On the computation of the barotropic mode of a free-surface world ocean model
The free-surface formulation of the equations of our world ocean model is briefly described. The barotropic mode equations are solved according to the split-explicit method, using different time steps for the external and internal modes. Because the numerical algorithm is implemented on the B-grid,...
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ftvliz:oai:oma.vliz.be:23755 2023-05-15T18:25:34+02:00 On the computation of the barotropic mode of a free-surface world ocean model Deleersnijder, E. Campin, J.M. 1995 application/pdf https://www.vliz.be/imisdocs/publications/262998.pdf en eng https://www.vliz.be/imisdocs/publications/262998.pdf info:eu-repo/semantics/openAccess iAnn.+Geophys.+13i+675-688 Barotropic mode Computation Equations Models info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 1995 ftvliz 2022-05-01T08:30:37Z The free-surface formulation of the equations of our world ocean model is briefly described. The barotropic mode equations are solved according to the split-explicit method, using different time steps for the external and internal modes. Because the numerical algorithm is implemented on the B-grid, a spurious, free-surface, two-grid interval mode may develop. This mode must be filtered out. The properties of two filters are theoretically investigated and their actual performance is tested in a series of numerical experiments. It is seen that one of these filters may severely perturb the local mass conservation, rendering it impossible to enforce the impermeability of the surface or the bottom of the ocean. The dynamics of the external mode is also examined, by studying the depth-integrated momentum equations. The depth-integral of the pressure force due to the slope of the ocean surface is approximately balanced by the depth-integral of the force ensuing from the horizontal variations of the density. The depth-integral of the Coriolis force is an order of magnitude smaller, except in the Southern Ocean. Two variational principles are resorted to for computing the fictitious ocean surface elevation corresponding to the approximate equilibrium between the dominant forces of the barotropic momentum equations. Article in Journal/Newspaper Southern Ocean Flanders Marine Institute (VLIZ): Open Marine Archive (OMA) Southern Ocean |
institution |
Open Polar |
collection |
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA) |
op_collection_id |
ftvliz |
language |
English |
topic |
Barotropic mode Computation Equations Models |
spellingShingle |
Barotropic mode Computation Equations Models Deleersnijder, E. Campin, J.M. On the computation of the barotropic mode of a free-surface world ocean model |
topic_facet |
Barotropic mode Computation Equations Models |
description |
The free-surface formulation of the equations of our world ocean model is briefly described. The barotropic mode equations are solved according to the split-explicit method, using different time steps for the external and internal modes. Because the numerical algorithm is implemented on the B-grid, a spurious, free-surface, two-grid interval mode may develop. This mode must be filtered out. The properties of two filters are theoretically investigated and their actual performance is tested in a series of numerical experiments. It is seen that one of these filters may severely perturb the local mass conservation, rendering it impossible to enforce the impermeability of the surface or the bottom of the ocean. The dynamics of the external mode is also examined, by studying the depth-integrated momentum equations. The depth-integral of the pressure force due to the slope of the ocean surface is approximately balanced by the depth-integral of the force ensuing from the horizontal variations of the density. The depth-integral of the Coriolis force is an order of magnitude smaller, except in the Southern Ocean. Two variational principles are resorted to for computing the fictitious ocean surface elevation corresponding to the approximate equilibrium between the dominant forces of the barotropic momentum equations. |
format |
Article in Journal/Newspaper |
author |
Deleersnijder, E. Campin, J.M. |
author_facet |
Deleersnijder, E. Campin, J.M. |
author_sort |
Deleersnijder, E. |
title |
On the computation of the barotropic mode of a free-surface world ocean model |
title_short |
On the computation of the barotropic mode of a free-surface world ocean model |
title_full |
On the computation of the barotropic mode of a free-surface world ocean model |
title_fullStr |
On the computation of the barotropic mode of a free-surface world ocean model |
title_full_unstemmed |
On the computation of the barotropic mode of a free-surface world ocean model |
title_sort |
on the computation of the barotropic mode of a free-surface world ocean model |
publishDate |
1995 |
url |
https://www.vliz.be/imisdocs/publications/262998.pdf |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
iAnn.+Geophys.+13i+675-688 |
op_relation |
https://www.vliz.be/imisdocs/publications/262998.pdf |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766207111602110464 |