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...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2022-06-01
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| Series: | Journal of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0022143021001118/type/journal_article |
| _version_ | 1811155748486381568 |
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| author | Øyvind A. Winton Sebastian B. Simonsen Anne M. Solgaard Robert McNabb Nanna B. Karlsson |
| author_facet | Øyvind A. Winton Sebastian B. Simonsen Anne M. Solgaard Robert McNabb Nanna B. Karlsson |
| author_sort | Øyvind A. Winton |
| collection | DOAJ |
| 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. |
| first_indexed | 2024-04-10T04:39:45Z |
| format | Article |
| id | doaj.art-90f9b016e80e432f895ef6ea3cf2ee95 |
| institution | Directory Open Access Journal |
| issn | 0022-1430 1727-5652 |
| language | English |
| last_indexed | 2024-04-10T04:39:45Z |
| publishDate | 2022-06-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Journal of Glaciology |
| spelling | doaj.art-90f9b016e80e432f895ef6ea3cf2ee952023-03-09T12:41:16ZengCambridge University PressJournal of Glaciology0022-14301727-56522022-06-016850351710.1017/jog.2021.111Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, GreenlandØyvind A. Winton0Sebastian B. Simonsen1https://orcid.org/0000-0001-9569-1294Anne M. Solgaard2https://orcid.org/0000-0002-8693-620XRobert McNabb3https://orcid.org/0000-0003-0016-493XNanna B. Karlsson4https://orcid.org/0000-0003-0423-8705Division of Geodesy and Earth Observation, DTU Space – National Space Institute, Technical University of Denmark, Lyngby, Denmark The Department of Glaciology and Climate, The Geological Survey of Denmark and Greenland (GEUS), Copenhagen, DenmarkDivision of Geodesy and Earth Observation, DTU Space – National Space Institute, Technical University of Denmark, Lyngby, DenmarkThe Department of Glaciology and Climate, The Geological Survey of Denmark and Greenland (GEUS), Copenhagen, DenmarkSchool of Geography & Environmental Sciences, Ulster University, Coleraine, UKThe Department of Glaciology and Climate, The Geological Survey of Denmark and Greenland (GEUS), Copenhagen, DenmarkBasal 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.https://www.cambridge.org/core/product/identifier/S0022143021001118/type/journal_articleArctic glaciologyglacier flowglacier modellingglacier surgesice velocity |
| spellingShingle | Øyvind A. Winton Sebastian B. Simonsen Anne M. Solgaard Robert McNabb Nanna B. Karlsson Basal stress controls ice-flow variability during a surge cycle of Hagen Bræ, Greenland Journal of Glaciology Arctic glaciology glacier flow glacier modelling glacier surges ice velocity |
| title | 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_short | 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 brae greenland |
| topic | Arctic glaciology glacier flow glacier modelling glacier surges ice velocity |
| url | https://www.cambridge.org/core/product/identifier/S0022143021001118/type/journal_article |
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