On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves
In the current ice-sheet models calving of ice shelves is based on phenomenological approaches. To obtain physics-based calving criteria, a viscoelastic Maxwell model is required accounting for short-term elastic and long-term viscous deformation. On timescales of months to years between calving eve...
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Cambridge University Press
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ftdoajarticles:oai:doaj.org/article:50c07ae8c0404b5995880017c949d259 2023-05-15T16:40:36+02:00 On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves JULIA CHRISTMANN RALF MÜLLER ANGELIKA HUMBERT 2019-04-01T00:00:00Z https://doi.org/10.1017/jog.2018.107 https://doaj.org/article/50c07ae8c0404b5995880017c949d259 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143018001077/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2018.107 0022-1430 1727-5652 https://doaj.org/article/50c07ae8c0404b5995880017c949d259 Journal of Glaciology, Vol 65, Pp 212-224 (2019) calving ice-sheet modeling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2019 ftdoajarticles https://doi.org/10.1017/jog.2018.107 2023-03-12T01:30:59Z In the current ice-sheet models calving of ice shelves is based on phenomenological approaches. To obtain physics-based calving criteria, a viscoelastic Maxwell model is required accounting for short-term elastic and long-term viscous deformation. On timescales of months to years between calving events, as well as on long timescales with several subsequent iceberg break-offs, deformations are no longer small and linearized strain measures cannot be used. We present a finite deformation framework of viscoelasticity and extend this model by a nonlinear Glen-type viscosity. A finite element implementation is used to compute stress and strain states in the vicinity of the ice-shelf calving front. Stress and strain maxima of small (linearized strain measure) and finite strain formulations differ by ~ 5% after 1 and by ~ 30% after 10 years, respectively. A finite deformation formulation reaches a critical stress or strain faster, thus calving rates will be higher, despite the fact that the exact critical values are not known. Nonlinear viscosity of Glen-type leads to higher stress values. The Maxwell material model formulation for finite deformations presented here can also be applied to other glaciological problems, for example, tidal forcing at grounding lines or closure of englacial and subglacial melt channels. Article in Journal/Newspaper Ice Sheet Ice Shelf Ice Shelves Journal of Glaciology Directory of Open Access Journals: DOAJ Articles Journal of Glaciology 65 250 212 224 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
calving ice-sheet modeling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
calving ice-sheet modeling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 JULIA CHRISTMANN RALF MÜLLER ANGELIKA HUMBERT On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
topic_facet |
calving ice-sheet modeling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
In the current ice-sheet models calving of ice shelves is based on phenomenological approaches. To obtain physics-based calving criteria, a viscoelastic Maxwell model is required accounting for short-term elastic and long-term viscous deformation. On timescales of months to years between calving events, as well as on long timescales with several subsequent iceberg break-offs, deformations are no longer small and linearized strain measures cannot be used. We present a finite deformation framework of viscoelasticity and extend this model by a nonlinear Glen-type viscosity. A finite element implementation is used to compute stress and strain states in the vicinity of the ice-shelf calving front. Stress and strain maxima of small (linearized strain measure) and finite strain formulations differ by ~ 5% after 1 and by ~ 30% after 10 years, respectively. A finite deformation formulation reaches a critical stress or strain faster, thus calving rates will be higher, despite the fact that the exact critical values are not known. Nonlinear viscosity of Glen-type leads to higher stress values. The Maxwell material model formulation for finite deformations presented here can also be applied to other glaciological problems, for example, tidal forcing at grounding lines or closure of englacial and subglacial melt channels. |
format |
Article in Journal/Newspaper |
author |
JULIA CHRISTMANN RALF MÜLLER ANGELIKA HUMBERT |
author_facet |
JULIA CHRISTMANN RALF MÜLLER ANGELIKA HUMBERT |
author_sort |
JULIA CHRISTMANN |
title |
On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
title_short |
On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
title_full |
On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
title_fullStr |
On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
title_full_unstemmed |
On nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
title_sort |
on nonlinear strain theory for a viscoelastic material model and its implications for calving of ice shelves |
publisher |
Cambridge University Press |
publishDate |
2019 |
url |
https://doi.org/10.1017/jog.2018.107 https://doaj.org/article/50c07ae8c0404b5995880017c949d259 |
genre |
Ice Sheet Ice Shelf Ice Shelves Journal of Glaciology |
genre_facet |
Ice Sheet Ice Shelf Ice Shelves Journal of Glaciology |
op_source |
Journal of Glaciology, Vol 65, Pp 212-224 (2019) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143018001077/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2018.107 0022-1430 1727-5652 https://doaj.org/article/50c07ae8c0404b5995880017c949d259 |
op_doi |
https://doi.org/10.1017/jog.2018.107 |
container_title |
Journal of Glaciology |
container_volume |
65 |
container_issue |
250 |
container_start_page |
212 |
op_container_end_page |
224 |
_version_ |
1766031000345772032 |