An assessment of basal melt parameterisations for Antarctic ice shelves
Ocean-induced ice-shelf melt is one of the largest uncertainty factors in the Antarctic contribution to future sea-level rise. Several parameterisations exist, linking oceanic properties in front of the ice shelf to melt at the base of the ice shelf, to force ice-sheet models. Here, we assess the po...
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Online Access: | https://nrl.northumbria.ac.uk/id/eprint/50887/ https://doi.org/10.5194/tc-16-4931-2022 https://nrl.northumbria.ac.uk/id/eprint/50887/1/tc-16-4931-2022.pdf |
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ftunivnorthumb:oai:nrl.northumbria.ac.uk:50887 2023-05-15T13:53:41+02:00 An assessment of basal melt parameterisations for Antarctic ice shelves Burgard, Clara Jourdain, Nicolas C. Reese, Ronja Jenkins, Adrian Mathiot, Pierre 2022-12-14 text https://nrl.northumbria.ac.uk/id/eprint/50887/ https://doi.org/10.5194/tc-16-4931-2022 https://nrl.northumbria.ac.uk/id/eprint/50887/1/tc-16-4931-2022.pdf en eng Coperincus https://nrl.northumbria.ac.uk/id/eprint/50887/1/tc-16-4931-2022.pdf Burgard, Clara, Jourdain, Nicolas C., Reese, Ronja, Jenkins, Adrian and Mathiot, Pierre (2022) An assessment of basal melt parameterisations for Antarctic ice shelves. The Cryosphere, 16 (12). pp. 4931-4975. ISSN 1994-0424 cc_by_4_0 CC-BY F600 Geology F700 Ocean Sciences F800 Physical and Terrestrial Geographical and Environmental Sciences Article PeerReviewed 2022 ftunivnorthumb https://doi.org/10.5194/tc-16-4931-2022 2022-12-15T23:31:01Z Ocean-induced ice-shelf melt is one of the largest uncertainty factors in the Antarctic contribution to future sea-level rise. Several parameterisations exist, linking oceanic properties in front of the ice shelf to melt at the base of the ice shelf, to force ice-sheet models. Here, we assess the potential of a range of these existing basal melt parameterisations to emulate basal melt rates simulated by a cavity-resolving ocean model on the circum-Antarctic scale. To do so, we perform two cross-validations, over time and over ice shelves respectively, and re-tune the parameterisations in a perfect-model approach, to compare the melt rates produced by the newly tuned parameterisations to the melt rates simulated by the ocean model. We find that the quadratic dependence of melt to thermal forcing without dependency on the individual ice-shelf slope and the plume parameterisation yield the best compromise, in terms of integrated shelf melt and spatial patterns. The box parameterisation, which separates the sub-shelf circulation into boxes, the PICOP parameterisation, which combines the box and plume parameterisation, and quadratic parameterisations with dependency on the ice slope yield basal melt rates further from the model reference. The linear parameterisation cannot be recommended as the resulting integrated ice-shelf melt is comparably furthest from the reference. When using offshore hydrographic input fields in comparison to properties on the continental shelf, all parameterisations perform worse; however, the box and the slope-dependent quadratic parameterisations yield the comparably best results. In addition to the new tuning, we provide uncertainty estimates for the tuned parameters. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves The Cryosphere Northumbria University, Newcastle: Northumbria Research Link (NRL) Antarctic The Antarctic The Cryosphere 16 12 4931 4975 |
institution |
Open Polar |
collection |
Northumbria University, Newcastle: Northumbria Research Link (NRL) |
op_collection_id |
ftunivnorthumb |
language |
English |
topic |
F600 Geology F700 Ocean Sciences F800 Physical and Terrestrial Geographical and Environmental Sciences |
spellingShingle |
F600 Geology F700 Ocean Sciences F800 Physical and Terrestrial Geographical and Environmental Sciences Burgard, Clara Jourdain, Nicolas C. Reese, Ronja Jenkins, Adrian Mathiot, Pierre An assessment of basal melt parameterisations for Antarctic ice shelves |
topic_facet |
F600 Geology F700 Ocean Sciences F800 Physical and Terrestrial Geographical and Environmental Sciences |
description |
Ocean-induced ice-shelf melt is one of the largest uncertainty factors in the Antarctic contribution to future sea-level rise. Several parameterisations exist, linking oceanic properties in front of the ice shelf to melt at the base of the ice shelf, to force ice-sheet models. Here, we assess the potential of a range of these existing basal melt parameterisations to emulate basal melt rates simulated by a cavity-resolving ocean model on the circum-Antarctic scale. To do so, we perform two cross-validations, over time and over ice shelves respectively, and re-tune the parameterisations in a perfect-model approach, to compare the melt rates produced by the newly tuned parameterisations to the melt rates simulated by the ocean model. We find that the quadratic dependence of melt to thermal forcing without dependency on the individual ice-shelf slope and the plume parameterisation yield the best compromise, in terms of integrated shelf melt and spatial patterns. The box parameterisation, which separates the sub-shelf circulation into boxes, the PICOP parameterisation, which combines the box and plume parameterisation, and quadratic parameterisations with dependency on the ice slope yield basal melt rates further from the model reference. The linear parameterisation cannot be recommended as the resulting integrated ice-shelf melt is comparably furthest from the reference. When using offshore hydrographic input fields in comparison to properties on the continental shelf, all parameterisations perform worse; however, the box and the slope-dependent quadratic parameterisations yield the comparably best results. In addition to the new tuning, we provide uncertainty estimates for the tuned parameters. |
format |
Article in Journal/Newspaper |
author |
Burgard, Clara Jourdain, Nicolas C. Reese, Ronja Jenkins, Adrian Mathiot, Pierre |
author_facet |
Burgard, Clara Jourdain, Nicolas C. Reese, Ronja Jenkins, Adrian Mathiot, Pierre |
author_sort |
Burgard, Clara |
title |
An assessment of basal melt parameterisations for Antarctic ice shelves |
title_short |
An assessment of basal melt parameterisations for Antarctic ice shelves |
title_full |
An assessment of basal melt parameterisations for Antarctic ice shelves |
title_fullStr |
An assessment of basal melt parameterisations for Antarctic ice shelves |
title_full_unstemmed |
An assessment of basal melt parameterisations for Antarctic ice shelves |
title_sort |
assessment of basal melt parameterisations for antarctic ice shelves |
publisher |
Coperincus |
publishDate |
2022 |
url |
https://nrl.northumbria.ac.uk/id/eprint/50887/ https://doi.org/10.5194/tc-16-4931-2022 https://nrl.northumbria.ac.uk/id/eprint/50887/1/tc-16-4931-2022.pdf |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves The Cryosphere |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves The Cryosphere |
op_relation |
https://nrl.northumbria.ac.uk/id/eprint/50887/1/tc-16-4931-2022.pdf Burgard, Clara, Jourdain, Nicolas C., Reese, Ronja, Jenkins, Adrian and Mathiot, Pierre (2022) An assessment of basal melt parameterisations for Antarctic ice shelves. The Cryosphere, 16 (12). pp. 4931-4975. ISSN 1994-0424 |
op_rights |
cc_by_4_0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-16-4931-2022 |
container_title |
The Cryosphere |
container_volume |
16 |
container_issue |
12 |
container_start_page |
4931 |
op_container_end_page |
4975 |
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1766259066329366528 |