Thinning leads to calving-style changes at Bowdoin Glacier, Greenland
Ice mass loss from the Greenland Ice Sheet is the largest single contributor to sea-level rise in the 21st century. The mass loss rate has accelerated in recent decades mainly due to thinning and retreat of its outlet glaciers. The diverse calving mechanisms responsible for tidewater glacier retreat...
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ftcopernicus:oai:publications.copernicus.org:tcd89382 2023-05-15T16:21:10+02:00 Thinning leads to calving-style changes at Bowdoin Glacier, Greenland Dongen, Eef C. H. Jouvet, Guillaume Sugiyama, Shin Podolskiy, Evgeny A. Funk, Martin Benn, Douglas I. Lindner, Fabian Bauder, Andreas Seguinot, Julien Leinss, Silvan Walter, Fabian 2020-10-14 application/pdf https://doi.org/10.5194/tc-2020-252 https://tc.copernicus.org/preprints/tc-2020-252/ eng eng doi:10.5194/tc-2020-252 https://tc.copernicus.org/preprints/tc-2020-252/ eISSN: 1994-0424 Text 2020 ftcopernicus https://doi.org/10.5194/tc-2020-252 2020-10-19T16:22:13Z Ice mass loss from the Greenland Ice Sheet is the largest single contributor to sea-level rise in the 21st century. The mass loss rate has accelerated in recent decades mainly due to thinning and retreat of its outlet glaciers. The diverse calving mechanisms responsible for tidewater glacier retreat are not fully understood yet. Since a tidewater glacier’s sensitivity to external forcings depends on its calving style, a detailed insight into calving processes is necessary to improve projections of ice sheet mass loss by calving. As tidewater glaciers are mostly thinning, their calving styles are expected to change. Here, we study calving behaviour changes under a thinning regime at Bowdoin Glacier, Northwest Greenland, by combining field and remote sensing data from 2015 to 2019. Previous studies showed that major calving events in 2015 and 2017 were driven by hydro-fracturing and melt-undercutting. New observations from UAV imagery and a GPS network installed at the calving front in 2019 suggest ungrounding and buoyant calving have recently occurred, as they show (1) increasing tidal modulation of vertical motion compared to previous years, (2) absence of a surface crevasse prior to calving, and (3) uplift and horizontal surface compression prior to calving. Furthermore, an inventory of calving events from 2015 to 2019 based on satellite imagery provides additional support for a change towards buoyant calving since it shows an increasing occurrence of calving events outside of the melt season. The observed change of calving style could lead to a possible retreat of the terminus, which has been stable since 2013. We therefore highlight the need for high-resolution monitoring to detect changing calving styles and numerical models that cover the full spectrum of calving mechanisms to improve projections of ice sheet mass loss by calving. Text glacier Greenland Ice Sheet Tidewater Copernicus Publications: E-Journals Bowdoin ENVELOPE(-69.317,-69.317,77.683,77.683) Greenland |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
Ice mass loss from the Greenland Ice Sheet is the largest single contributor to sea-level rise in the 21st century. The mass loss rate has accelerated in recent decades mainly due to thinning and retreat of its outlet glaciers. The diverse calving mechanisms responsible for tidewater glacier retreat are not fully understood yet. Since a tidewater glacier’s sensitivity to external forcings depends on its calving style, a detailed insight into calving processes is necessary to improve projections of ice sheet mass loss by calving. As tidewater glaciers are mostly thinning, their calving styles are expected to change. Here, we study calving behaviour changes under a thinning regime at Bowdoin Glacier, Northwest Greenland, by combining field and remote sensing data from 2015 to 2019. Previous studies showed that major calving events in 2015 and 2017 were driven by hydro-fracturing and melt-undercutting. New observations from UAV imagery and a GPS network installed at the calving front in 2019 suggest ungrounding and buoyant calving have recently occurred, as they show (1) increasing tidal modulation of vertical motion compared to previous years, (2) absence of a surface crevasse prior to calving, and (3) uplift and horizontal surface compression prior to calving. Furthermore, an inventory of calving events from 2015 to 2019 based on satellite imagery provides additional support for a change towards buoyant calving since it shows an increasing occurrence of calving events outside of the melt season. The observed change of calving style could lead to a possible retreat of the terminus, which has been stable since 2013. We therefore highlight the need for high-resolution monitoring to detect changing calving styles and numerical models that cover the full spectrum of calving mechanisms to improve projections of ice sheet mass loss by calving. |
format |
Text |
author |
Dongen, Eef C. H. Jouvet, Guillaume Sugiyama, Shin Podolskiy, Evgeny A. Funk, Martin Benn, Douglas I. Lindner, Fabian Bauder, Andreas Seguinot, Julien Leinss, Silvan Walter, Fabian |
spellingShingle |
Dongen, Eef C. H. Jouvet, Guillaume Sugiyama, Shin Podolskiy, Evgeny A. Funk, Martin Benn, Douglas I. Lindner, Fabian Bauder, Andreas Seguinot, Julien Leinss, Silvan Walter, Fabian Thinning leads to calving-style changes at Bowdoin Glacier, Greenland |
author_facet |
Dongen, Eef C. H. Jouvet, Guillaume Sugiyama, Shin Podolskiy, Evgeny A. Funk, Martin Benn, Douglas I. Lindner, Fabian Bauder, Andreas Seguinot, Julien Leinss, Silvan Walter, Fabian |
author_sort |
Dongen, Eef C. H. |
title |
Thinning leads to calving-style changes at Bowdoin Glacier, Greenland |
title_short |
Thinning leads to calving-style changes at Bowdoin Glacier, Greenland |
title_full |
Thinning leads to calving-style changes at Bowdoin Glacier, Greenland |
title_fullStr |
Thinning leads to calving-style changes at Bowdoin Glacier, Greenland |
title_full_unstemmed |
Thinning leads to calving-style changes at Bowdoin Glacier, Greenland |
title_sort |
thinning leads to calving-style changes at bowdoin glacier, greenland |
publishDate |
2020 |
url |
https://doi.org/10.5194/tc-2020-252 https://tc.copernicus.org/preprints/tc-2020-252/ |
long_lat |
ENVELOPE(-69.317,-69.317,77.683,77.683) |
geographic |
Bowdoin Greenland |
geographic_facet |
Bowdoin Greenland |
genre |
glacier Greenland Ice Sheet Tidewater |
genre_facet |
glacier Greenland Ice Sheet Tidewater |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-2020-252 https://tc.copernicus.org/preprints/tc-2020-252/ |
op_doi |
https://doi.org/10.5194/tc-2020-252 |
_version_ |
1766009178183172096 |