Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3)
Oceanic melting beneath ice shelves is the main driver of the current mass loss of the Antarctic ice sheet and is mostly parameterised in stand-alone ice-sheet modelling. Parameterisations are crude representations of reality, and their response to ocean warming has not been compared to 3-D ocean–ic...
Published in: | Geoscientific Model Development |
---|---|
Main Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2019
|
Subjects: | |
Online Access: | https://doi.org/10.5194/gmd-12-2255-2019 https://doaj.org/article/a4efdcd09f0e4b0c93bddb8f01e2f34c |
id |
ftdoajarticles:oai:doaj.org/article:a4efdcd09f0e4b0c93bddb8f01e2f34c |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:a4efdcd09f0e4b0c93bddb8f01e2f34c 2023-05-15T13:58:10+02:00 Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) L. Favier N. C. Jourdain A. Jenkins N. Merino G. Durand O. Gagliardini F. Gillet-Chaulet P. Mathiot 2019-06-01T00:00:00Z https://doi.org/10.5194/gmd-12-2255-2019 https://doaj.org/article/a4efdcd09f0e4b0c93bddb8f01e2f34c EN eng Copernicus Publications https://www.geosci-model-dev.net/12/2255/2019/gmd-12-2255-2019.pdf https://doaj.org/toc/1991-959X https://doaj.org/toc/1991-9603 doi:10.5194/gmd-12-2255-2019 1991-959X 1991-9603 https://doaj.org/article/a4efdcd09f0e4b0c93bddb8f01e2f34c Geoscientific Model Development, Vol 12, Pp 2255-2283 (2019) Geology QE1-996.5 article 2019 ftdoajarticles https://doi.org/10.5194/gmd-12-2255-2019 2022-12-31T04:47:55Z Oceanic melting beneath ice shelves is the main driver of the current mass loss of the Antarctic ice sheet and is mostly parameterised in stand-alone ice-sheet modelling. Parameterisations are crude representations of reality, and their response to ocean warming has not been compared to 3-D ocean–ice-sheet coupled models. Here, we assess various melting parameterisations ranging from simple scalings with far-field thermal driving to emulators of box and plume models, using a new coupling framework combining the ocean model NEMO and the ice-sheet model Elmer/Ice. We define six idealised one-century scenarios for the far-field ocean ranging from cold to warm, and representative of potential futures for typical Antarctic ice shelves. The scenarios are used to constrain an idealised geometry of the Pine Island glacier representative of a relatively small cavity. Melt rates and sea-level contributions obtained with the parameterised stand-alone ice-sheet model are compared to the coupled model results. The plume parameterisations give good results for cold scenarios but fail and underestimate sea level contribution by tens of percent for warm(ing) scenarios, which may be improved by adapting its empirical scaling. The box parameterisation with five boxes compares fairly well to the coupled results for almost all scenarios, but further work is needed to grasp the correct number of boxes. For simple scalings, the comparison to the coupled framework shows that a quadratic as opposed to linear dependency on thermal forcing is required. In addition, the quadratic dependency is improved when melting depends on both local and non-local, i.e. averaged over the ice shelf, thermal forcing. The results of both the box and the two quadratic parameterisations fall within or close to the coupled model uncertainty. All parameterisations overestimate melting for thin ice shelves while underestimating melting in deep water near the grounding line. Further work is therefore needed to assess the validity of these melting ... Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Pine Island Glacier Directory of Open Access Journals: DOAJ Articles Antarctic Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) The Antarctic Geoscientific Model Development 12 6 2255 2283 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Geology QE1-996.5 |
spellingShingle |
Geology QE1-996.5 L. Favier N. C. Jourdain A. Jenkins N. Merino G. Durand O. Gagliardini F. Gillet-Chaulet P. Mathiot Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) |
topic_facet |
Geology QE1-996.5 |
description |
Oceanic melting beneath ice shelves is the main driver of the current mass loss of the Antarctic ice sheet and is mostly parameterised in stand-alone ice-sheet modelling. Parameterisations are crude representations of reality, and their response to ocean warming has not been compared to 3-D ocean–ice-sheet coupled models. Here, we assess various melting parameterisations ranging from simple scalings with far-field thermal driving to emulators of box and plume models, using a new coupling framework combining the ocean model NEMO and the ice-sheet model Elmer/Ice. We define six idealised one-century scenarios for the far-field ocean ranging from cold to warm, and representative of potential futures for typical Antarctic ice shelves. The scenarios are used to constrain an idealised geometry of the Pine Island glacier representative of a relatively small cavity. Melt rates and sea-level contributions obtained with the parameterised stand-alone ice-sheet model are compared to the coupled model results. The plume parameterisations give good results for cold scenarios but fail and underestimate sea level contribution by tens of percent for warm(ing) scenarios, which may be improved by adapting its empirical scaling. The box parameterisation with five boxes compares fairly well to the coupled results for almost all scenarios, but further work is needed to grasp the correct number of boxes. For simple scalings, the comparison to the coupled framework shows that a quadratic as opposed to linear dependency on thermal forcing is required. In addition, the quadratic dependency is improved when melting depends on both local and non-local, i.e. averaged over the ice shelf, thermal forcing. The results of both the box and the two quadratic parameterisations fall within or close to the coupled model uncertainty. All parameterisations overestimate melting for thin ice shelves while underestimating melting in deep water near the grounding line. Further work is therefore needed to assess the validity of these melting ... |
format |
Article in Journal/Newspaper |
author |
L. Favier N. C. Jourdain A. Jenkins N. Merino G. Durand O. Gagliardini F. Gillet-Chaulet P. Mathiot |
author_facet |
L. Favier N. C. Jourdain A. Jenkins N. Merino G. Durand O. Gagliardini F. Gillet-Chaulet P. Mathiot |
author_sort |
L. Favier |
title |
Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) |
title_short |
Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) |
title_full |
Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) |
title_fullStr |
Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) |
title_full_unstemmed |
Assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model NEMO(v3.6)–Elmer/Ice(v8.3) |
title_sort |
assessment of sub-shelf melting parameterisations using the ocean–ice-sheet coupled model nemo(v3.6)–elmer/ice(v8.3) |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/gmd-12-2255-2019 https://doaj.org/article/a4efdcd09f0e4b0c93bddb8f01e2f34c |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Antarctic Pine Island Glacier The Antarctic |
geographic_facet |
Antarctic Pine Island Glacier The Antarctic |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Pine Island Glacier |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf Ice Shelves Pine Island Glacier |
op_source |
Geoscientific Model Development, Vol 12, Pp 2255-2283 (2019) |
op_relation |
https://www.geosci-model-dev.net/12/2255/2019/gmd-12-2255-2019.pdf https://doaj.org/toc/1991-959X https://doaj.org/toc/1991-9603 doi:10.5194/gmd-12-2255-2019 1991-959X 1991-9603 https://doaj.org/article/a4efdcd09f0e4b0c93bddb8f01e2f34c |
op_doi |
https://doi.org/10.5194/gmd-12-2255-2019 |
container_title |
Geoscientific Model Development |
container_volume |
12 |
container_issue |
6 |
container_start_page |
2255 |
op_container_end_page |
2283 |
_version_ |
1766266272954187776 |