Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean
Melting at the base of floating ice shelves is a dominant term in the overall Antarctic mass budget. This study applies a high-resolution regional ice shelf/ocean model, constrained by observations, to (i) quantify present basal mass loss at the Fimbul Ice Shelf (FIS); and (ii) investigate the ocean...
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Online Access: | https://doi.org/10.1016/j.ocemod.2014.07.004 http://ecite.utas.edu.au/94379 |
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ftunivtasecite:oai:ecite.utas.edu.au:94379 2023-05-15T13:37:24+02:00 Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean Hattermann, T Smedsrud, LH Nost, OA Lilly, JM Galton-Fenzi, B 2014 application/pdf https://doi.org/10.1016/j.ocemod.2014.07.004 http://ecite.utas.edu.au/94379 en eng Elsevier Sci Ltd http://ecite.utas.edu.au/94379/1/Hattermann_2014_Fimbul_ice_shelf.pdf http://dx.doi.org/10.1016/j.ocemod.2014.07.004 Hattermann, T and Smedsrud, LH and Nost, OA and Lilly, JM and Galton-Fenzi, B, Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean, Ocean Modelling, 82 pp. 28-44. ISSN 1463-5003 (2014) [Refereed Article] http://ecite.utas.edu.au/94379 Earth Sciences Oceanography Physical Oceanography Refereed Article PeerReviewed 2014 ftunivtasecite https://doi.org/10.1016/j.ocemod.2014.07.004 2019-12-13T21:57:00Z Melting at the base of floating ice shelves is a dominant term in the overall Antarctic mass budget. This study applies a high-resolution regional ice shelf/ocean model, constrained by observations, to (i) quantify present basal mass loss at the Fimbul Ice Shelf (FIS); and (ii) investigate the oceanic mechanisms that govern the heat supply to ice shelves in the Eastern Weddell Sea. The simulations confirm the low melt rates suggested by observations and show that melting is primarily determined by the depth of the coastal thermocline, regulating deep ocean heat fluxes towards the ice. Furthermore, the uneven distribution of ice shelf area at different depths modulates the melting response to oceanic forcing, causing the existence of two distinct states of melting at the FIS. In the simulated present-day state, only small amounts of Modified Warm Deep Water enter the continental shelf, and ocean temperatures beneath the ice are close to the surface freezing point. The basal mass loss in this so-called state of shallow melting is mainly controlled by the seasonal inflow of solar-heated surface water affecting large areas of shallow ice in the upper part of the cavity. This is in contrast to a state of deep melting, in which the thermocline rises above the shelf break depth, establishing a continuous inflow of Warm Deep Water towards the deep ice. The transition between the two states is found to be determined by a complex response of the Antarctic Slope Front overturning circulation to varying climate forcings. A proper representation of these frontal dynamics in climate models will therefore be crucial when assessing the evolution of ice shelf basal melting along this sector of Antarctica. Article in Journal/Newspaper Antarc* Antarctic Antarctica Fimbul Ice Shelf Ice Shelf Ice Shelves Weddell Sea eCite UTAS (University of Tasmania) Antarctic Fimbul Ice Shelf ENVELOPE(-0.500,-0.500,-70.750,-70.750) The Antarctic Weddell Weddell Sea Ocean Modelling 82 28 44 |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Oceanography Physical Oceanography |
spellingShingle |
Earth Sciences Oceanography Physical Oceanography Hattermann, T Smedsrud, LH Nost, OA Lilly, JM Galton-Fenzi, B Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean |
topic_facet |
Earth Sciences Oceanography Physical Oceanography |
description |
Melting at the base of floating ice shelves is a dominant term in the overall Antarctic mass budget. This study applies a high-resolution regional ice shelf/ocean model, constrained by observations, to (i) quantify present basal mass loss at the Fimbul Ice Shelf (FIS); and (ii) investigate the oceanic mechanisms that govern the heat supply to ice shelves in the Eastern Weddell Sea. The simulations confirm the low melt rates suggested by observations and show that melting is primarily determined by the depth of the coastal thermocline, regulating deep ocean heat fluxes towards the ice. Furthermore, the uneven distribution of ice shelf area at different depths modulates the melting response to oceanic forcing, causing the existence of two distinct states of melting at the FIS. In the simulated present-day state, only small amounts of Modified Warm Deep Water enter the continental shelf, and ocean temperatures beneath the ice are close to the surface freezing point. The basal mass loss in this so-called state of shallow melting is mainly controlled by the seasonal inflow of solar-heated surface water affecting large areas of shallow ice in the upper part of the cavity. This is in contrast to a state of deep melting, in which the thermocline rises above the shelf break depth, establishing a continuous inflow of Warm Deep Water towards the deep ice. The transition between the two states is found to be determined by a complex response of the Antarctic Slope Front overturning circulation to varying climate forcings. A proper representation of these frontal dynamics in climate models will therefore be crucial when assessing the evolution of ice shelf basal melting along this sector of Antarctica. |
format |
Article in Journal/Newspaper |
author |
Hattermann, T Smedsrud, LH Nost, OA Lilly, JM Galton-Fenzi, B |
author_facet |
Hattermann, T Smedsrud, LH Nost, OA Lilly, JM Galton-Fenzi, B |
author_sort |
Hattermann, T |
title |
Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean |
title_short |
Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean |
title_full |
Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean |
title_fullStr |
Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean |
title_full_unstemmed |
Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean |
title_sort |
eddy-resolving simulations of the fimbul ice shelf cavity circulation: basal melting and exchange with open ocean |
publisher |
Elsevier Sci Ltd |
publishDate |
2014 |
url |
https://doi.org/10.1016/j.ocemod.2014.07.004 http://ecite.utas.edu.au/94379 |
long_lat |
ENVELOPE(-0.500,-0.500,-70.750,-70.750) |
geographic |
Antarctic Fimbul Ice Shelf The Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Fimbul Ice Shelf The Antarctic Weddell Weddell Sea |
genre |
Antarc* Antarctic Antarctica Fimbul Ice Shelf Ice Shelf Ice Shelves Weddell Sea |
genre_facet |
Antarc* Antarctic Antarctica Fimbul Ice Shelf Ice Shelf Ice Shelves Weddell Sea |
op_relation |
http://ecite.utas.edu.au/94379/1/Hattermann_2014_Fimbul_ice_shelf.pdf http://dx.doi.org/10.1016/j.ocemod.2014.07.004 Hattermann, T and Smedsrud, LH and Nost, OA and Lilly, JM and Galton-Fenzi, B, Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with open ocean, Ocean Modelling, 82 pp. 28-44. ISSN 1463-5003 (2014) [Refereed Article] http://ecite.utas.edu.au/94379 |
op_doi |
https://doi.org/10.1016/j.ocemod.2014.07.004 |
container_title |
Ocean Modelling |
container_volume |
82 |
container_start_page |
28 |
op_container_end_page |
44 |
_version_ |
1766091331986259968 |