Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3)
Ice flow forced by gravity is governed by the full Stokes (FS) equations, which are computationally expensive to solve due to the nonlinearity introduced by the rheology. Therefore, approximations to the FS equations are commonly used, especially when modeling a marine ice sheet (ice sheet, ice shel...
Published in: | Geoscientific Model Development |
---|---|
Main Authors: | , , , , , , , |
Format: | Text |
Language: | English |
Published: |
2018
|
Subjects: | |
Online Access: | https://doi.org/10.5194/gmd-11-4563-2018 https://gmd.copernicus.org/articles/11/4563/2018/ |
id |
ftcopernicus:oai:publications.copernicus.org:gmd64847 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:gmd64847 2023-05-15T16:40:00+02:00 Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) Dongen, Eef C. H. Kirchner, Nina Gijzen, Martin B. Wal, Roderik S. W. Zwinger, Thomas Cheng, Gong Lötstedt, Per Sydow, Lina 2018-11-16 application/pdf https://doi.org/10.5194/gmd-11-4563-2018 https://gmd.copernicus.org/articles/11/4563/2018/ eng eng doi:10.5194/gmd-11-4563-2018 https://gmd.copernicus.org/articles/11/4563/2018/ eISSN: 1991-9603 Text 2018 ftcopernicus https://doi.org/10.5194/gmd-11-4563-2018 2020-07-20T16:23:02Z Ice flow forced by gravity is governed by the full Stokes (FS) equations, which are computationally expensive to solve due to the nonlinearity introduced by the rheology. Therefore, approximations to the FS equations are commonly used, especially when modeling a marine ice sheet (ice sheet, ice shelf, and/or ice stream) for 10 3 years or longer. The shallow ice approximation (SIA) and shallow shelf approximation (SSA) are commonly used but are accurate only for certain parts of an ice sheet. Here, we report a novel way of iteratively coupling FS and SSA that has been implemented in Elmer/Ice and applied to conceptual marine ice sheets. The FS–SSA coupling appears to be very accurate; the relative error in velocity compared to FS is below 0.5 % for diagnostic runs and below 5 % for prognostic runs. Results for grounding line dynamics obtained with the FS–SSA coupling are similar to those obtained from an FS model in an experiment with a periodical temperature forcing over 3000 years that induces grounding line advance and retreat. The rapid convergence of the FS–SSA coupling shows a large potential for reducing computation time, such that modeling a marine ice sheet for thousands of years should become feasible in the near future. Despite inefficient matrix assembly in the current implementation, computation time is reduced by 32 %, when the coupling is applied to a 3-D ice shelf. Text Ice Sheet Ice Shelf Copernicus Publications: E-Journals Geoscientific Model Development 11 11 4563 4576 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Ice flow forced by gravity is governed by the full Stokes (FS) equations, which are computationally expensive to solve due to the nonlinearity introduced by the rheology. Therefore, approximations to the FS equations are commonly used, especially when modeling a marine ice sheet (ice sheet, ice shelf, and/or ice stream) for 10 3 years or longer. The shallow ice approximation (SIA) and shallow shelf approximation (SSA) are commonly used but are accurate only for certain parts of an ice sheet. Here, we report a novel way of iteratively coupling FS and SSA that has been implemented in Elmer/Ice and applied to conceptual marine ice sheets. The FS–SSA coupling appears to be very accurate; the relative error in velocity compared to FS is below 0.5 % for diagnostic runs and below 5 % for prognostic runs. Results for grounding line dynamics obtained with the FS–SSA coupling are similar to those obtained from an FS model in an experiment with a periodical temperature forcing over 3000 years that induces grounding line advance and retreat. The rapid convergence of the FS–SSA coupling shows a large potential for reducing computation time, such that modeling a marine ice sheet for thousands of years should become feasible in the near future. Despite inefficient matrix assembly in the current implementation, computation time is reduced by 32 %, when the coupling is applied to a 3-D ice shelf. |
format |
Text |
author |
Dongen, Eef C. H. Kirchner, Nina Gijzen, Martin B. Wal, Roderik S. W. Zwinger, Thomas Cheng, Gong Lötstedt, Per Sydow, Lina |
spellingShingle |
Dongen, Eef C. H. Kirchner, Nina Gijzen, Martin B. Wal, Roderik S. W. Zwinger, Thomas Cheng, Gong Lötstedt, Per Sydow, Lina Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) |
author_facet |
Dongen, Eef C. H. Kirchner, Nina Gijzen, Martin B. Wal, Roderik S. W. Zwinger, Thomas Cheng, Gong Lötstedt, Per Sydow, Lina |
author_sort |
Dongen, Eef C. H. |
title |
Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) |
title_short |
Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) |
title_full |
Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) |
title_fullStr |
Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) |
title_full_unstemmed |
Dynamically coupling full Stokes and shallow shelf approximation for marine ice sheet flow using Elmer/Ice (v8.3) |
title_sort |
dynamically coupling full stokes and shallow shelf approximation for marine ice sheet flow using elmer/ice (v8.3) |
publishDate |
2018 |
url |
https://doi.org/10.5194/gmd-11-4563-2018 https://gmd.copernicus.org/articles/11/4563/2018/ |
genre |
Ice Sheet Ice Shelf |
genre_facet |
Ice Sheet Ice Shelf |
op_source |
eISSN: 1991-9603 |
op_relation |
doi:10.5194/gmd-11-4563-2018 https://gmd.copernicus.org/articles/11/4563/2018/ |
op_doi |
https://doi.org/10.5194/gmd-11-4563-2018 |
container_title |
Geoscientific Model Development |
container_volume |
11 |
container_issue |
11 |
container_start_page |
4563 |
op_container_end_page |
4576 |
_version_ |
1766030358929735680 |