Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls
Quantitative satellite observations only provide an assessment of ice sheet mass loss over the last four decades. To assess long-term drivers of ice sheet change, geological records are needed. Here we present the first millennial-scale reconstruction of David Glacier, the largest East Antarctic out...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , , , , , , , , , , , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2021
|
Subjects: | |
Online Access: | http://hdl.handle.net/11568/1133125 https://doi.org/10.5194/tc-15-5447-2021 https://tc.copernicus.org/articles/15/5447/2021/ |
id |
ftunivpisairis:oai:arpi.unipi.it:11568/1133125 |
---|---|
record_format |
openpolar |
spelling |
ftunivpisairis:oai:arpi.unipi.it:11568/1133125 2024-04-14T08:02:18+00:00 Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls Stutz J. Mackintosh A. Norton K. Whitmore R. Baroni C. Jamieson S. S. R. Jones R. S. Balco G. Salvatore M. C. Casale S. Lee J. I. Seong Y. B. McKay R. Vargo L. J. Lowry D. Spector P. Christl M. Ochs S. I. Di Nicola L. Iarossi M. Stuart F. Woodruff T. Stutz, J. Mackintosh, A. Norton, K. Whitmore, R. Baroni, C. Jamieson, S. S. R. Jones, R. S. Balco, G. Salvatore, M. C. Casale, S. Lee, J. I. Seong, Y. B. Mckay, R. Vargo, L. J. Lowry, D. Spector, P. Christl, M. Ochs, S. I. Di Nicola, L. Iarossi, M. Stuart, F. Woodruff, T. 2021 ELETTRONICO http://hdl.handle.net/11568/1133125 https://doi.org/10.5194/tc-15-5447-2021 https://tc.copernicus.org/articles/15/5447/2021/ eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000728469500001 volume:15 issue:12 firstpage:5447 lastpage:5471 numberofpages:25 journal:THE CRYOSPHERE http://hdl.handle.net/11568/1133125 doi:10.5194/tc-15-5447-2021 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85121235835 https://tc.copernicus.org/articles/15/5447/2021/ info:eu-repo/semantics/article 2021 ftunivpisairis https://doi.org/10.5194/tc-15-5447-2021 2024-03-21T19:21:41Z Quantitative satellite observations only provide an assessment of ice sheet mass loss over the last four decades. To assess long-term drivers of ice sheet change, geological records are needed. Here we present the first millennial-scale reconstruction of David Glacier, the largest East Antarctic outlet glacier in Victoria Land. To reconstruct changes in ice thickness, we use surface exposure ages of glacial erratics deposited on nunataks adjacent to fast-flowing sections of David Glacier. We then use numerical modelling experiments to determine the drivers of glacial thinning. Thinning profiles derived from 45 10Be and 3He surface exposure ages show David Glacier experienced rapid thinning of up to 2ĝm/yr during the mid-Holocene (ĝ1/4ĝ6.5ĝka). Thinning slowed at 6ĝka, suggesting the initial formation of the Drygalski Ice Tongue at this time. Our work, along with ice thinning records from adjacent glaciers, shows simultaneous glacier thinning in this sector of the Transantarctic Mountains occurred 4-7ĝkyr after the peak period of ice thinning indicated in a suite of published ice sheet models. The timing and rapidity of the reconstructed thinning at David Glacier is similar to reconstructions in the Amundsen and Weddell embayments. To identify the drivers of glacier thinning along the David Glacier, we use a glacier flowline model designed for calving glaciers and compare modelled results against our geological data. We show that glacier thinning and marine-based grounding-line retreat are controlled by either enhanced sub-ice-shelf melting, reduced lateral buttressing or a combination of the two, leading to marine ice sheet instability. Such rapid glacier thinning events during the mid-Holocene are not fully captured in continental- or catchment-scale numerical modelling reconstructions. Together, our chronology and modelling identify and constrain the drivers of a ĝ1/4ĝ2000-year period of dynamic glacier thinning in the recent geological past. Article in Journal/Newspaper Antarc* Antarctic Antarctica David Glacier Ice Sheet Ice Shelf Victoria Land ARPI - Archivio della Ricerca dell'Università di Pisa Antarctic Victoria Land Transantarctic Mountains Weddell Drygalski ENVELOPE(-61.000,-61.000,-64.717,-64.717) Drygalski Ice Tongue ENVELOPE(163.500,163.500,-75.400,-75.400) David Glacier ENVELOPE(160.000,160.000,-75.333,-75.333) The Cryosphere 15 12 5447 5471 |
institution |
Open Polar |
collection |
ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
description |
Quantitative satellite observations only provide an assessment of ice sheet mass loss over the last four decades. To assess long-term drivers of ice sheet change, geological records are needed. Here we present the first millennial-scale reconstruction of David Glacier, the largest East Antarctic outlet glacier in Victoria Land. To reconstruct changes in ice thickness, we use surface exposure ages of glacial erratics deposited on nunataks adjacent to fast-flowing sections of David Glacier. We then use numerical modelling experiments to determine the drivers of glacial thinning. Thinning profiles derived from 45 10Be and 3He surface exposure ages show David Glacier experienced rapid thinning of up to 2ĝm/yr during the mid-Holocene (ĝ1/4ĝ6.5ĝka). Thinning slowed at 6ĝka, suggesting the initial formation of the Drygalski Ice Tongue at this time. Our work, along with ice thinning records from adjacent glaciers, shows simultaneous glacier thinning in this sector of the Transantarctic Mountains occurred 4-7ĝkyr after the peak period of ice thinning indicated in a suite of published ice sheet models. The timing and rapidity of the reconstructed thinning at David Glacier is similar to reconstructions in the Amundsen and Weddell embayments. To identify the drivers of glacier thinning along the David Glacier, we use a glacier flowline model designed for calving glaciers and compare modelled results against our geological data. We show that glacier thinning and marine-based grounding-line retreat are controlled by either enhanced sub-ice-shelf melting, reduced lateral buttressing or a combination of the two, leading to marine ice sheet instability. Such rapid glacier thinning events during the mid-Holocene are not fully captured in continental- or catchment-scale numerical modelling reconstructions. Together, our chronology and modelling identify and constrain the drivers of a ĝ1/4ĝ2000-year period of dynamic glacier thinning in the recent geological past. |
author2 |
Stutz, J. Mackintosh, A. Norton, K. Whitmore, R. Baroni, C. Jamieson, S. S. R. Jones, R. S. Balco, G. Salvatore, M. C. Casale, S. Lee, J. I. Seong, Y. B. Mckay, R. Vargo, L. J. Lowry, D. Spector, P. Christl, M. Ochs, S. I. Di Nicola, L. Iarossi, M. Stuart, F. Woodruff, T. |
format |
Article in Journal/Newspaper |
author |
Stutz J. Mackintosh A. Norton K. Whitmore R. Baroni C. Jamieson S. S. R. Jones R. S. Balco G. Salvatore M. C. Casale S. Lee J. I. Seong Y. B. McKay R. Vargo L. J. Lowry D. Spector P. Christl M. Ochs S. I. Di Nicola L. Iarossi M. Stuart F. Woodruff T. |
spellingShingle |
Stutz J. Mackintosh A. Norton K. Whitmore R. Baroni C. Jamieson S. S. R. Jones R. S. Balco G. Salvatore M. C. Casale S. Lee J. I. Seong Y. B. McKay R. Vargo L. J. Lowry D. Spector P. Christl M. Ochs S. I. Di Nicola L. Iarossi M. Stuart F. Woodruff T. Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls |
author_facet |
Stutz J. Mackintosh A. Norton K. Whitmore R. Baroni C. Jamieson S. S. R. Jones R. S. Balco G. Salvatore M. C. Casale S. Lee J. I. Seong Y. B. McKay R. Vargo L. J. Lowry D. Spector P. Christl M. Ochs S. I. Di Nicola L. Iarossi M. Stuart F. Woodruff T. |
author_sort |
Stutz J. |
title |
Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls |
title_short |
Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls |
title_full |
Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls |
title_fullStr |
Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls |
title_full_unstemmed |
Mid-Holocene thinning of David Glacier, Antarctica: Chronology and controls |
title_sort |
mid-holocene thinning of david glacier, antarctica: chronology and controls |
publishDate |
2021 |
url |
http://hdl.handle.net/11568/1133125 https://doi.org/10.5194/tc-15-5447-2021 https://tc.copernicus.org/articles/15/5447/2021/ |
long_lat |
ENVELOPE(-61.000,-61.000,-64.717,-64.717) ENVELOPE(163.500,163.500,-75.400,-75.400) ENVELOPE(160.000,160.000,-75.333,-75.333) |
geographic |
Antarctic Victoria Land Transantarctic Mountains Weddell Drygalski Drygalski Ice Tongue David Glacier |
geographic_facet |
Antarctic Victoria Land Transantarctic Mountains Weddell Drygalski Drygalski Ice Tongue David Glacier |
genre |
Antarc* Antarctic Antarctica David Glacier Ice Sheet Ice Shelf Victoria Land |
genre_facet |
Antarc* Antarctic Antarctica David Glacier Ice Sheet Ice Shelf Victoria Land |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000728469500001 volume:15 issue:12 firstpage:5447 lastpage:5471 numberofpages:25 journal:THE CRYOSPHERE http://hdl.handle.net/11568/1133125 doi:10.5194/tc-15-5447-2021 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85121235835 https://tc.copernicus.org/articles/15/5447/2021/ |
op_doi |
https://doi.org/10.5194/tc-15-5447-2021 |
container_title |
The Cryosphere |
container_volume |
15 |
container_issue |
12 |
container_start_page |
5447 |
op_container_end_page |
5471 |
_version_ |
1796313977595101184 |