Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations
Ice-shelf basal melting is the largest contributor to the negative mass balance of the Antarctic ice sheet. However, current implementations of ice/ocean interactions in ice-sheet models disagree with the distribution of sub-shelf melt and freezing rates revealed by recent observational studies. Her...
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Cambridge University Press
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ftdoajarticles:oai:doaj.org/article:d630a2cded13499dbd2e48eb90d92f0b 2023-05-15T13:35:10+02:00 Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations JORGE BERNALES IRINA ROGOZHINA MAIK THOMAS 2017-08-01T00:00:00Z https://doi.org/10.1017/jog.2017.42 https://doaj.org/article/d630a2cded13499dbd2e48eb90d92f0b EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143017000429/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2017.42 0022-1430 1727-5652 https://doaj.org/article/d630a2cded13499dbd2e48eb90d92f0b Journal of Glaciology, Vol 63, Pp 731-744 (2017) Antarctic glaciology basal melt ice/ocean interactions ice-sheet modelling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2017 ftdoajarticles https://doi.org/10.1017/jog.2017.42 2023-03-12T01:30:59Z Ice-shelf basal melting is the largest contributor to the negative mass balance of the Antarctic ice sheet. However, current implementations of ice/ocean interactions in ice-sheet models disagree with the distribution of sub-shelf melt and freezing rates revealed by recent observational studies. Here we present a novel combination of a continental-scale ice flow model and a calibration technique to derive the spatial distribution of basal melting and freezing rates for the whole Antarctic ice-shelf system. The modelled ice-sheet equilibrium state is evaluated against topographic and velocity observations. Our high-resolution (10-km spacing) simulation predicts an equilibrium ice-shelf basal mass balance of −1648.7 Gt a−1 that increases to −1917.0 Gt a−1 when the observed ice-shelf thinning rates are taken into account. Our estimates reproduce the complexity of the basal mass balance of Antarctic ice shelves, providing a reference for parameterisations of sub-shelf ocean/ice interactions in continental ice-sheet models. We perform a sensitivity analysis to assess the effects of variations in the model set-up, showing that the retrieved estimates of basal melting and freezing rates are largely insensitive to changes in the internal model parameters, but respond strongly to a reduction of model resolution and the uncertainty in the input datasets. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Journal of Glaciology Directory of Open Access Journals: DOAJ Articles Antarctic The Antarctic Journal of Glaciology 63 240 731 744 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Antarctic glaciology basal melt ice/ocean interactions ice-sheet modelling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Antarctic glaciology basal melt ice/ocean interactions ice-sheet modelling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 JORGE BERNALES IRINA ROGOZHINA MAIK THOMAS Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations |
topic_facet |
Antarctic glaciology basal melt ice/ocean interactions ice-sheet modelling ice shelves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
Ice-shelf basal melting is the largest contributor to the negative mass balance of the Antarctic ice sheet. However, current implementations of ice/ocean interactions in ice-sheet models disagree with the distribution of sub-shelf melt and freezing rates revealed by recent observational studies. Here we present a novel combination of a continental-scale ice flow model and a calibration technique to derive the spatial distribution of basal melting and freezing rates for the whole Antarctic ice-shelf system. The modelled ice-sheet equilibrium state is evaluated against topographic and velocity observations. Our high-resolution (10-km spacing) simulation predicts an equilibrium ice-shelf basal mass balance of −1648.7 Gt a−1 that increases to −1917.0 Gt a−1 when the observed ice-shelf thinning rates are taken into account. Our estimates reproduce the complexity of the basal mass balance of Antarctic ice shelves, providing a reference for parameterisations of sub-shelf ocean/ice interactions in continental ice-sheet models. We perform a sensitivity analysis to assess the effects of variations in the model set-up, showing that the retrieved estimates of basal melting and freezing rates are largely insensitive to changes in the internal model parameters, but respond strongly to a reduction of model resolution and the uncertainty in the input datasets. |
format |
Article in Journal/Newspaper |
author |
JORGE BERNALES IRINA ROGOZHINA MAIK THOMAS |
author_facet |
JORGE BERNALES IRINA ROGOZHINA MAIK THOMAS |
author_sort |
JORGE BERNALES |
title |
Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations |
title_short |
Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations |
title_full |
Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations |
title_fullStr |
Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations |
title_full_unstemmed |
Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations |
title_sort |
melting and freezing under antarctic ice shelves from a combination of ice-sheet modelling and observations |
publisher |
Cambridge University Press |
publishDate |
2017 |
url |
https://doi.org/10.1017/jog.2017.42 https://doaj.org/article/d630a2cded13499dbd2e48eb90d92f0b |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Journal of Glaciology |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Journal of Glaciology |
op_source |
Journal of Glaciology, Vol 63, Pp 731-744 (2017) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143017000429/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2017.42 0022-1430 1727-5652 https://doaj.org/article/d630a2cded13499dbd2e48eb90d92f0b |
op_doi |
https://doi.org/10.1017/jog.2017.42 |
container_title |
Journal of Glaciology |
container_volume |
63 |
container_issue |
240 |
container_start_page |
731 |
op_container_end_page |
744 |
_version_ |
1766061774408253440 |