A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf
The West Antarctic ice sheet is confined by a large area of ice shelves, fed by inland ice through fast flowing ice streams. The dynamics of the grounding line, which is the line-boundary between grounded ice and the downstream ice shelf, has a major influence on the dynamics of the whole ice sheet....
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ftdoajarticles:oai:doaj.org/article:1388041a06e84ad686ae30f9a9a1912a 2023-05-15T13:54:00+02:00 A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf L. Favier O. Gagliardini G. Durand T. Zwinger 2012-01-01T00:00:00Z https://doi.org/10.5194/tc-6-101-2012 https://doaj.org/article/1388041a06e84ad686ae30f9a9a1912a EN eng Copernicus Publications http://www.the-cryosphere.net/6/101/2012/tc-6-101-2012.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-6-101-2012 1994-0416 1994-0424 https://doaj.org/article/1388041a06e84ad686ae30f9a9a1912a The Cryosphere, Vol 6, Iss 1, Pp 101-112 (2012) Environmental sciences GE1-350 Geology QE1-996.5 article 2012 ftdoajarticles https://doi.org/10.5194/tc-6-101-2012 2022-12-31T14:41:58Z The West Antarctic ice sheet is confined by a large area of ice shelves, fed by inland ice through fast flowing ice streams. The dynamics of the grounding line, which is the line-boundary between grounded ice and the downstream ice shelf, has a major influence on the dynamics of the whole ice sheet. However, most ice sheet models use simplifications of the flow equations, as they do not include all the stress components, and are known to fail in their representation of the grounding line dynamics. Here, we present a 3-D full Stokes model of a marine ice sheet, in which the flow problem is coupled with the evolution of the upper and lower free surfaces, and the position of the grounding line is determined by solving a contact problem between the shelf/sheet lower surface and the bedrock. Simulations are performed using the open-source finite-element code Elmer/Ice within a parallel environment. The model's ability to cope with a curved grounding line and the effect of a pinning point beneath the ice shelf are investigated through prognostic simulations. Starting from a steady state, the sea level is slightly decreased to create a contact point between a seamount and the ice shelf. The model predicts a dramatic decrease of the shelf velocities, leading to an advance of the grounding line until both grounded zones merge together, during which an ice rumple forms above the contact area at the pinning point. Finally, we show that once the contact is created, increasing the sea level to its initial value does not release the pinning point and has no effect on the ice dynamics, indicating a stabilising effect of pinning points. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves The Cryosphere Directory of Open Access Journals: DOAJ Articles Antarctic Contact Point ENVELOPE(-56.997,-56.997,-63.374,-63.374) West Antarctic Ice Sheet The Cryosphere 6 1 101 112 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 L. Favier O. Gagliardini G. Durand T. Zwinger A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
The West Antarctic ice sheet is confined by a large area of ice shelves, fed by inland ice through fast flowing ice streams. The dynamics of the grounding line, which is the line-boundary between grounded ice and the downstream ice shelf, has a major influence on the dynamics of the whole ice sheet. However, most ice sheet models use simplifications of the flow equations, as they do not include all the stress components, and are known to fail in their representation of the grounding line dynamics. Here, we present a 3-D full Stokes model of a marine ice sheet, in which the flow problem is coupled with the evolution of the upper and lower free surfaces, and the position of the grounding line is determined by solving a contact problem between the shelf/sheet lower surface and the bedrock. Simulations are performed using the open-source finite-element code Elmer/Ice within a parallel environment. The model's ability to cope with a curved grounding line and the effect of a pinning point beneath the ice shelf are investigated through prognostic simulations. Starting from a steady state, the sea level is slightly decreased to create a contact point between a seamount and the ice shelf. The model predicts a dramatic decrease of the shelf velocities, leading to an advance of the grounding line until both grounded zones merge together, during which an ice rumple forms above the contact area at the pinning point. Finally, we show that once the contact is created, increasing the sea level to its initial value does not release the pinning point and has no effect on the ice dynamics, indicating a stabilising effect of pinning points. |
format |
Article in Journal/Newspaper |
author |
L. Favier O. Gagliardini G. Durand T. Zwinger |
author_facet |
L. Favier O. Gagliardini G. Durand T. Zwinger |
author_sort |
L. Favier |
title |
A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
title_short |
A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
title_full |
A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
title_fullStr |
A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
title_full_unstemmed |
A three-dimensional full Stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
title_sort |
three-dimensional full stokes model of the grounding line dynamics: effect of a pinning point beneath the ice shelf |
publisher |
Copernicus Publications |
publishDate |
2012 |
url |
https://doi.org/10.5194/tc-6-101-2012 https://doaj.org/article/1388041a06e84ad686ae30f9a9a1912a |
long_lat |
ENVELOPE(-56.997,-56.997,-63.374,-63.374) |
geographic |
Antarctic Contact Point West Antarctic Ice Sheet |
geographic_facet |
Antarctic Contact Point West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves The Cryosphere |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves The Cryosphere |
op_source |
The Cryosphere, Vol 6, Iss 1, Pp 101-112 (2012) |
op_relation |
http://www.the-cryosphere.net/6/101/2012/tc-6-101-2012.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-6-101-2012 1994-0416 1994-0424 https://doaj.org/article/1388041a06e84ad686ae30f9a9a1912a |
op_doi |
https://doi.org/10.5194/tc-6-101-2012 |
container_title |
The Cryosphere |
container_volume |
6 |
container_issue |
1 |
container_start_page |
101 |
op_container_end_page |
112 |
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1766259506048663552 |