Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier
By the end of 2018 Kangerlussuaq Glacier in southeast Greenland had retreated further inland than at any time in the past 80 years and its terminus was approaching a region of retrograde bed slope from where further rapid retreat would have been inevitable. Here we show that the retreat occurred bec...
Published in: | The Cryosphere |
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Online Access: | https://doi.org/10.5194/tc-13-2303-2019 https://tc.copernicus.org/articles/13/2303/2019/ |
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ftcopernicus:oai:publications.copernicus.org:tc73174 2023-05-15T16:20:56+02:00 Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier Bevan, Suzanne L. Luckman, Adrian J. Benn, Douglas I. Cowton, Tom Todd, Joe 2019-09-05 application/pdf https://doi.org/10.5194/tc-13-2303-2019 https://tc.copernicus.org/articles/13/2303/2019/ eng eng doi:10.5194/tc-13-2303-2019 https://tc.copernicus.org/articles/13/2303/2019/ eISSN: 1994-0424 Text 2019 ftcopernicus https://doi.org/10.5194/tc-13-2303-2019 2020-07-20T16:22:40Z By the end of 2018 Kangerlussuaq Glacier in southeast Greenland had retreated further inland than at any time in the past 80 years and its terminus was approaching a region of retrograde bed slope from where further rapid retreat would have been inevitable. Here we show that the retreat occurred because the glacier failed to advance during the winters of 2016/17 and 2017/18 owing to a weakened proglacial mélange. This mixture of sea ice and icebergs is normally rigid enough to inhibit calving in winter, but for 2 consecutive years it repeatedly collapsed, allowing Kangerlussuaq Glacier to continue to calve all year round. The mélange break-ups followed the establishment of anomalously warm surface water on the continental shelf during 2016, which likely penetrated the fjord. As calving continued uninterrupted from summer 2016 to the end of 2018 the glacier accelerated by 35 % and thinned by 35 m. These observations demonstrate the importance of near-surface ocean temperatures in tidewater glacier stability and show that it is not only deep-ocean warming that can lead to glacier retreat. During winter 2019 a persistent mélange reformed and the glacier readvanced by 3.5 km. Text glacier Greenland Kangerlussuaq Sea ice Tidewater Copernicus Publications: E-Journals Greenland Kangerlussuaq ENVELOPE(-55.633,-55.633,72.633,72.633) The Cryosphere 13 9 2303 2315 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
By the end of 2018 Kangerlussuaq Glacier in southeast Greenland had retreated further inland than at any time in the past 80 years and its terminus was approaching a region of retrograde bed slope from where further rapid retreat would have been inevitable. Here we show that the retreat occurred because the glacier failed to advance during the winters of 2016/17 and 2017/18 owing to a weakened proglacial mélange. This mixture of sea ice and icebergs is normally rigid enough to inhibit calving in winter, but for 2 consecutive years it repeatedly collapsed, allowing Kangerlussuaq Glacier to continue to calve all year round. The mélange break-ups followed the establishment of anomalously warm surface water on the continental shelf during 2016, which likely penetrated the fjord. As calving continued uninterrupted from summer 2016 to the end of 2018 the glacier accelerated by 35 % and thinned by 35 m. These observations demonstrate the importance of near-surface ocean temperatures in tidewater glacier stability and show that it is not only deep-ocean warming that can lead to glacier retreat. During winter 2019 a persistent mélange reformed and the glacier readvanced by 3.5 km. |
format |
Text |
author |
Bevan, Suzanne L. Luckman, Adrian J. Benn, Douglas I. Cowton, Tom Todd, Joe |
spellingShingle |
Bevan, Suzanne L. Luckman, Adrian J. Benn, Douglas I. Cowton, Tom Todd, Joe Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier |
author_facet |
Bevan, Suzanne L. Luckman, Adrian J. Benn, Douglas I. Cowton, Tom Todd, Joe |
author_sort |
Bevan, Suzanne L. |
title |
Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier |
title_short |
Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier |
title_full |
Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier |
title_fullStr |
Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier |
title_full_unstemmed |
Impact of warming shelf waters on ice mélange and terminus retreat at a large SE Greenland glacier |
title_sort |
impact of warming shelf waters on ice mélange and terminus retreat at a large se greenland glacier |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-2303-2019 https://tc.copernicus.org/articles/13/2303/2019/ |
long_lat |
ENVELOPE(-55.633,-55.633,72.633,72.633) |
geographic |
Greenland Kangerlussuaq |
geographic_facet |
Greenland Kangerlussuaq |
genre |
glacier Greenland Kangerlussuaq Sea ice Tidewater |
genre_facet |
glacier Greenland Kangerlussuaq Sea ice Tidewater |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-13-2303-2019 https://tc.copernicus.org/articles/13/2303/2019/ |
op_doi |
https://doi.org/10.5194/tc-13-2303-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
9 |
container_start_page |
2303 |
op_container_end_page |
2315 |
_version_ |
1766008951123476480 |