Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland
Basal conditions play an essential role in the dynamics of outlet glaciers, but direct observations at the bed of glaciers are challenging to obtain. Instead, inverse methods can be used to infer basal parameters from surface observations. Here, we use a simple ice-flow model as a forward model in a...
Published in: | Journal of Glaciology |
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Language: | English |
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2022
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Online Access: | https://orbit.dtu.dk/en/publications/ddf52d34-5958-4afe-b9bc-18d815f9e593 https://doi.org/10.1017/jog.2021.111 https://backend.orbit.dtu.dk/ws/files/276067662/basal_stress_controls_ice_flow_variability_during_a_surge_cycle_of_hagen_brae_greenland.pdf |
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ftdtupubl:oai:pure.atira.dk:publications/ddf52d34-5958-4afe-b9bc-18d815f9e593 2023-05-15T15:04:27+02:00 Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland Winton, Øyvind A. Simonsen, Sebastian B. Solgaard, Anne M. McNabb, Robert Karlsson, Nanna B. 2022 application/pdf https://orbit.dtu.dk/en/publications/ddf52d34-5958-4afe-b9bc-18d815f9e593 https://doi.org/10.1017/jog.2021.111 https://backend.orbit.dtu.dk/ws/files/276067662/basal_stress_controls_ice_flow_variability_during_a_surge_cycle_of_hagen_brae_greenland.pdf eng eng info:eu-repo/semantics/openAccess Winton , Ø A , Simonsen , S B , Solgaard , A M , McNabb , R & Karlsson , N B 2022 , ' Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland ' , Journal of Glaciology , vol. 68 , no. 269 , pp. 503–517 . https://doi.org/10.1017/jog.2021.111 Arctic glaciology Glacier flow Glacier modelling Glacier surges Ice velocity article 2022 ftdtupubl https://doi.org/10.1017/jog.2021.111 2023-01-12T00:16:09Z Basal conditions play an essential role in the dynamics of outlet glaciers, but direct observations at the bed of glaciers are challenging to obtain. Instead, inverse methods can be used to infer basal parameters from surface observations. Here, we use a simple ice-flow model as a forward model in an inversion scheme to retrieve the spatio-temporally variable basal stress parameter for Hagen Bræ, North Greenland, from 1990 to 2020. Hagen Bræ is a surge-type glacier with up to an order of magnitude variability of winter velocities near the grounding line. We find that downstream changes in the basal stress parameter can explain most of the variation of flow velocity, and we further identify a region of high resistance ∼20-40 km from the grounding line. We hypothesise that this region of high resistance plays an important role in controlling glacier discharge. Article in Journal/Newspaper Arctic glacier Greenland Journal of Glaciology North Greenland Technical University of Denmark: DTU Orbit Arctic Greenland Hagen ENVELOPE(6.545,6.545,62.545,62.545) Journal of Glaciology 68 269 503 517 |
institution |
Open Polar |
collection |
Technical University of Denmark: DTU Orbit |
op_collection_id |
ftdtupubl |
language |
English |
topic |
Arctic glaciology Glacier flow Glacier modelling Glacier surges Ice velocity |
spellingShingle |
Arctic glaciology Glacier flow Glacier modelling Glacier surges Ice velocity Winton, Øyvind A. Simonsen, Sebastian B. Solgaard, Anne M. McNabb, Robert Karlsson, Nanna B. Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland |
topic_facet |
Arctic glaciology Glacier flow Glacier modelling Glacier surges Ice velocity |
description |
Basal conditions play an essential role in the dynamics of outlet glaciers, but direct observations at the bed of glaciers are challenging to obtain. Instead, inverse methods can be used to infer basal parameters from surface observations. Here, we use a simple ice-flow model as a forward model in an inversion scheme to retrieve the spatio-temporally variable basal stress parameter for Hagen Bræ, North Greenland, from 1990 to 2020. Hagen Bræ is a surge-type glacier with up to an order of magnitude variability of winter velocities near the grounding line. We find that downstream changes in the basal stress parameter can explain most of the variation of flow velocity, and we further identify a region of high resistance ∼20-40 km from the grounding line. We hypothesise that this region of high resistance plays an important role in controlling glacier discharge. |
format |
Article in Journal/Newspaper |
author |
Winton, Øyvind A. Simonsen, Sebastian B. Solgaard, Anne M. McNabb, Robert Karlsson, Nanna B. |
author_facet |
Winton, Øyvind A. Simonsen, Sebastian B. Solgaard, Anne M. McNabb, Robert Karlsson, Nanna B. |
author_sort |
Winton, Øyvind A. |
title |
Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland |
title_short |
Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland |
title_full |
Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland |
title_fullStr |
Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland |
title_full_unstemmed |
Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland |
title_sort |
basal stress controls ice-flow variability during a surge cycle of hagen bræ, greenland |
publishDate |
2022 |
url |
https://orbit.dtu.dk/en/publications/ddf52d34-5958-4afe-b9bc-18d815f9e593 https://doi.org/10.1017/jog.2021.111 https://backend.orbit.dtu.dk/ws/files/276067662/basal_stress_controls_ice_flow_variability_during_a_surge_cycle_of_hagen_brae_greenland.pdf |
long_lat |
ENVELOPE(6.545,6.545,62.545,62.545) |
geographic |
Arctic Greenland Hagen |
geographic_facet |
Arctic Greenland Hagen |
genre |
Arctic glacier Greenland Journal of Glaciology North Greenland |
genre_facet |
Arctic glacier Greenland Journal of Glaciology North Greenland |
op_source |
Winton , Ø A , Simonsen , S B , Solgaard , A M , McNabb , R & Karlsson , N B 2022 , ' Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland ' , Journal of Glaciology , vol. 68 , no. 269 , pp. 503–517 . https://doi.org/10.1017/jog.2021.111 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1017/jog.2021.111 |
container_title |
Journal of Glaciology |
container_volume |
68 |
container_issue |
269 |
container_start_page |
503 |
op_container_end_page |
517 |
_version_ |
1766336221852729344 |