Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions
Outlet glaciers in Greenland are undergoing retreat and diffusive thinning in response to external forcings, but the rates and magnitudes of these responses differ from glacier to glacier for unclear reasons. We test how changes in ice overburden pressure and basal lubrication affect diffusive thinn...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Cambridge University Press
2024-01-01
|
| Series: | Journal of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0022143024000509/type/journal_article |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850030273652064256 |
|---|---|
| author | Donglai Yang Kristin Poinar Sophie Nowicki Beata Csatho |
| author_facet | Donglai Yang Kristin Poinar Sophie Nowicki Beata Csatho |
| author_sort | Donglai Yang |
| collection | DOAJ |
| description | Outlet glaciers in Greenland are undergoing retreat and diffusive thinning in response to external forcings, but the rates and magnitudes of these responses differ from glacier to glacier for unclear reasons. We test how changes in ice overburden pressure and basal lubrication affect diffusive thinning rates and their spatial patterns by conducting numerical experiments over various idealized Greenland-like glacier domains. We find that ~10 km frontal retreat over a decade can produce sustained thinning rates as large as 16 m a−1 due to ice overburden pressure changes, at outlet glaciers with high basal drag (>60 kPa) and lateral resistive stress (>70 kPa). Localized basal lubrication perturbations induce upstream thinning and downstream thickening up to 12 m a−1; the duration of the lubrication forcing generally has a greater effect than its intensity on induced thickness changes. Lastly, episodic grounding line retreats over a rough bed produce a stepped time series of thinning broadly consistent with observations of dynamic elevation change on multiple Greenland glaciers. Our findings highlight the critical role of the total grounding zone – not ice front position – through the resistive stress change in relation to total glacier thinning. |
| format | Article |
| id | doaj-art-84aa12d899e44dbb9602fa1d10e51d31 |
| institution | DOAJ |
| issn | 0022-1430 1727-5652 |
| language | English |
| publishDate | 2024-01-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Journal of Glaciology |
| spelling | doaj-art-84aa12d899e44dbb9602fa1d10e51d312025-08-20T02:59:15ZengCambridge University PressJournal of Glaciology0022-14301727-56522024-01-017010.1017/jog.2024.50Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditionsDonglai Yang0https://orcid.org/0000-0002-1209-4740Kristin Poinar1Sophie Nowicki2Beata Csatho3https://orcid.org/0000-0001-7768-4998Department of Geological Sciences, University at Buffalo, Buffalo, NY, USADepartment of Geological Sciences, University at Buffalo, Buffalo, NY, USA RENEW Institute, University at Buffalo, Buffalo, NY, USADepartment of Geological Sciences, University at Buffalo, Buffalo, NY, USA RENEW Institute, University at Buffalo, Buffalo, NY, USADepartment of Geological Sciences, University at Buffalo, Buffalo, NY, USAOutlet glaciers in Greenland are undergoing retreat and diffusive thinning in response to external forcings, but the rates and magnitudes of these responses differ from glacier to glacier for unclear reasons. We test how changes in ice overburden pressure and basal lubrication affect diffusive thinning rates and their spatial patterns by conducting numerical experiments over various idealized Greenland-like glacier domains. We find that ~10 km frontal retreat over a decade can produce sustained thinning rates as large as 16 m a−1 due to ice overburden pressure changes, at outlet glaciers with high basal drag (>60 kPa) and lateral resistive stress (>70 kPa). Localized basal lubrication perturbations induce upstream thinning and downstream thickening up to 12 m a−1; the duration of the lubrication forcing generally has a greater effect than its intensity on induced thickness changes. Lastly, episodic grounding line retreats over a rough bed produce a stepped time series of thinning broadly consistent with observations of dynamic elevation change on multiple Greenland glaciers. Our findings highlight the critical role of the total grounding zone – not ice front position – through the resistive stress change in relation to total glacier thinning.https://www.cambridge.org/core/product/identifier/S0022143024000509/type/journal_articleglacier modelingglaciological model experimentsice dynamicsice thickness measurements |
| spellingShingle | Donglai Yang Kristin Poinar Sophie Nowicki Beata Csatho Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions Journal of Glaciology glacier modeling glaciological model experiments ice dynamics ice thickness measurements |
| title | Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions |
| title_full | Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions |
| title_fullStr | Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions |
| title_full_unstemmed | Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions |
| title_short | Characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions |
| title_sort | characteristics of dynamic thickness change across diverse outlet glacier geometries and basal conditions |
| topic | glacier modeling glaciological model experiments ice dynamics ice thickness measurements |
| url | https://www.cambridge.org/core/product/identifier/S0022143024000509/type/journal_article |
| work_keys_str_mv | AT donglaiyang characteristicsofdynamicthicknesschangeacrossdiverseoutletglaciergeometriesandbasalconditions AT kristinpoinar characteristicsofdynamicthicknesschangeacrossdiverseoutletglaciergeometriesandbasalconditions AT sophienowicki characteristicsofdynamicthicknesschangeacrossdiverseoutletglaciergeometriesandbasalconditions AT beatacsatho characteristicsofdynamicthicknesschangeacrossdiverseoutletglaciergeometriesandbasalconditions |