Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study
The oceanic forcing of basal melt under floating ice shelves in Greenland and Antarctica is one of the major sources of uncertainty in climate ice sheet modelling. We use a high resolution, non-hydrostatic configuration of the Massachusetts Institute of Technology general circulation model (MITgcm)...
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00063940 2023-05-15T13:49:22+02:00 Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study Wiskandt, Jonathan Koszalka, Inga Monika Nilsson, Johan 2022-12 electronic https://doi.org/10.5194/egusphere-2022-1296 https://noa.gwlb.de/receive/cop_mods_00063940 https://egusphere.copernicus.org/preprints/egusphere-2022-1296/egusphere-2022-1296.pdf eng eng Copernicus Publications https://doi.org/10.5194/egusphere-2022-1296 https://noa.gwlb.de/receive/cop_mods_00063940 https://egusphere.copernicus.org/preprints/egusphere-2022-1296/egusphere-2022-1296.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/restrictedAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2022 ftnonlinearchiv https://doi.org/10.5194/egusphere-2022-1296 2022-12-19T00:12:46Z The oceanic forcing of basal melt under floating ice shelves in Greenland and Antarctica is one of the major sources of uncertainty in climate ice sheet modelling. We use a high resolution, non-hydrostatic configuration of the Massachusetts Institute of Technology general circulation model (MITgcm) to investigate basal melt rates and melt driven circulation in the Sherard Osborn Fjord under the floating tongue of Ryder Glacier, northwestern Greenland. The control model configuration, based on the first ever observational survey by Ryder 2019 Expedition, yielded melt rates consistent with independent satellite estimates. A protocol of model sensitivity experiments quantified the response to oceanic thermal forcing due to a warming Atlantic Water, and to the buoyancy input from the subglacial discharge of surface fresh water. We found that the average basal melt rates show a nonlinear response to oceanic forcing in the lower range of ocean temperatures, while the response becomes indistinguishable from linear for higher ocean temperatures, which unifies the results from previous modelling studies of other marine terminating glaciers. The melt rate response to subglacial discharge is sublinear, consistent with other studies. The melt rates and circulation below the ice tongue exhibit a spatial pattern that is determined by the ambient density stratification. Article in Journal/Newspaper Antarc* Antarctica glacier Greenland Ice Sheet Ice Shelves Sherard Osborn fjord Niedersächsisches Online-Archiv NOA Greenland Osborn ENVELOPE(-120.378,-120.378,56.604,56.604) Ryder ENVELOPE(-68.333,-68.333,-67.566,-67.566) Ryder Glacier ENVELOPE(-67.250,-67.250,-71.116,-71.116) Sherard Osborn Fjord ENVELOPE(-51.833,-51.833,82.083,82.083) |
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Open Polar |
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Niedersächsisches Online-Archiv NOA |
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ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
spellingShingle |
article Verlagsveröffentlichung Wiskandt, Jonathan Koszalka, Inga Monika Nilsson, Johan Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study |
topic_facet |
article Verlagsveröffentlichung |
description |
The oceanic forcing of basal melt under floating ice shelves in Greenland and Antarctica is one of the major sources of uncertainty in climate ice sheet modelling. We use a high resolution, non-hydrostatic configuration of the Massachusetts Institute of Technology general circulation model (MITgcm) to investigate basal melt rates and melt driven circulation in the Sherard Osborn Fjord under the floating tongue of Ryder Glacier, northwestern Greenland. The control model configuration, based on the first ever observational survey by Ryder 2019 Expedition, yielded melt rates consistent with independent satellite estimates. A protocol of model sensitivity experiments quantified the response to oceanic thermal forcing due to a warming Atlantic Water, and to the buoyancy input from the subglacial discharge of surface fresh water. We found that the average basal melt rates show a nonlinear response to oceanic forcing in the lower range of ocean temperatures, while the response becomes indistinguishable from linear for higher ocean temperatures, which unifies the results from previous modelling studies of other marine terminating glaciers. The melt rate response to subglacial discharge is sublinear, consistent with other studies. The melt rates and circulation below the ice tongue exhibit a spatial pattern that is determined by the ambient density stratification. |
format |
Article in Journal/Newspaper |
author |
Wiskandt, Jonathan Koszalka, Inga Monika Nilsson, Johan |
author_facet |
Wiskandt, Jonathan Koszalka, Inga Monika Nilsson, Johan |
author_sort |
Wiskandt, Jonathan |
title |
Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study |
title_short |
Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study |
title_full |
Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study |
title_fullStr |
Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study |
title_full_unstemmed |
Basal melt rates and ocean circulation under the Ryder Glacier ice tongue and their response to climate warming: a high resolution modelling study |
title_sort |
basal melt rates and ocean circulation under the ryder glacier ice tongue and their response to climate warming: a high resolution modelling study |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://doi.org/10.5194/egusphere-2022-1296 https://noa.gwlb.de/receive/cop_mods_00063940 https://egusphere.copernicus.org/preprints/egusphere-2022-1296/egusphere-2022-1296.pdf |
long_lat |
ENVELOPE(-120.378,-120.378,56.604,56.604) ENVELOPE(-68.333,-68.333,-67.566,-67.566) ENVELOPE(-67.250,-67.250,-71.116,-71.116) ENVELOPE(-51.833,-51.833,82.083,82.083) |
geographic |
Greenland Osborn Ryder Ryder Glacier Sherard Osborn Fjord |
geographic_facet |
Greenland Osborn Ryder Ryder Glacier Sherard Osborn Fjord |
genre |
Antarc* Antarctica glacier Greenland Ice Sheet Ice Shelves Sherard Osborn fjord |
genre_facet |
Antarc* Antarctica glacier Greenland Ice Sheet Ice Shelves Sherard Osborn fjord |
op_relation |
https://doi.org/10.5194/egusphere-2022-1296 https://noa.gwlb.de/receive/cop_mods_00063940 https://egusphere.copernicus.org/preprints/egusphere-2022-1296/egusphere-2022-1296.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/restrictedAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/egusphere-2022-1296 |
_version_ |
1766251247979986944 |