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...
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ftdoajarticles:oai:doaj.org/article:5e25dbbfc8784b6f8c75fde9e169d87a 2023-05-15T13:56:57+02:00 Mid-Holocene thinning of David Glacier, Antarctica: chronology and controls J. Stutz A. Mackintosh K. Norton R. Whitmore C. Baroni S. S. R. Jamieson R. S. Jones G. Balco M. C. Salvatore S. Casale J. I. Lee Y. B. Seong R. McKay L. J. Vargo D. Lowry P. Spector M. Christl S. Ivy Ochs L. Di Nicola M. Iarossi F. Stuart T. Woodruff 2021-12-01T00:00:00Z https://doi.org/10.5194/tc-15-5447-2021 https://doaj.org/article/5e25dbbfc8784b6f8c75fde9e169d87a EN eng Copernicus Publications https://tc.copernicus.org/articles/15/5447/2021/tc-15-5447-2021.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-15-5447-2021 1994-0416 1994-0424 https://doaj.org/article/5e25dbbfc8784b6f8c75fde9e169d87a The Cryosphere, Vol 15, Pp 5447-5471 (2021) Environmental sciences GE1-350 Geology QE1-996.5 article 2021 ftdoajarticles https://doi.org/10.5194/tc-15-5447-2021 2022-12-31T08:05:29Z 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 10 Be and 3 He surface exposure ages show David Glacier experienced rapid thinning of up to 2 m/yr during the mid-Holocene ( ∼ 6.5 ka). Thinning slowed at 6 ka, 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 4–7 kyr 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 ∼ 2000-year period of dynamic glacier thinning in the recent geological past. Article in Journal/Newspaper Antarc* Antarctic Antarctica David Glacier Ice Sheet Ice Shelf The Cryosphere Victoria Land Directory of Open Access Journals: DOAJ Articles Antarctic David Glacier ENVELOPE(160.000,160.000,-75.333,-75.333) Drygalski ENVELOPE(-61.000,-61.000,-64.717,-64.717) Drygalski Ice Tongue ENVELOPE(163.500,163.500,-75.400,-75.400) Transantarctic Mountains Victoria Land Weddell The Cryosphere 15 12 5447 5471 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 J. Stutz A. Mackintosh K. Norton R. Whitmore C. Baroni S. S. R. Jamieson R. S. Jones G. Balco M. C. Salvatore S. Casale J. I. Lee Y. B. Seong R. McKay L. J. Vargo D. Lowry P. Spector M. Christl S. Ivy Ochs L. Di Nicola M. Iarossi F. Stuart T. Woodruff Mid-Holocene thinning of David Glacier, Antarctica: chronology and controls |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
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 10 Be and 3 He surface exposure ages show David Glacier experienced rapid thinning of up to 2 m/yr during the mid-Holocene ( ∼ 6.5 ka). Thinning slowed at 6 ka, 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 4–7 kyr 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 ∼ 2000-year period of dynamic glacier thinning in the recent geological past. |
format |
Article in Journal/Newspaper |
author |
J. Stutz A. Mackintosh K. Norton R. Whitmore C. Baroni S. S. R. Jamieson R. S. Jones G. Balco M. C. Salvatore S. Casale J. I. Lee Y. B. Seong R. McKay L. J. Vargo D. Lowry P. Spector M. Christl S. Ivy Ochs L. Di Nicola M. Iarossi F. Stuart T. Woodruff |
author_facet |
J. Stutz A. Mackintosh K. Norton R. Whitmore C. Baroni S. S. R. Jamieson R. S. Jones G. Balco M. C. Salvatore S. Casale J. I. Lee Y. B. Seong R. McKay L. J. Vargo D. Lowry P. Spector M. Christl S. Ivy Ochs L. Di Nicola M. Iarossi F. Stuart T. Woodruff |
author_sort |
J. Stutz |
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 |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/tc-15-5447-2021 https://doaj.org/article/5e25dbbfc8784b6f8c75fde9e169d87a |
long_lat |
ENVELOPE(160.000,160.000,-75.333,-75.333) ENVELOPE(-61.000,-61.000,-64.717,-64.717) ENVELOPE(163.500,163.500,-75.400,-75.400) |
geographic |
Antarctic David Glacier Drygalski Drygalski Ice Tongue Transantarctic Mountains Victoria Land Weddell |
geographic_facet |
Antarctic David Glacier Drygalski Drygalski Ice Tongue Transantarctic Mountains Victoria Land Weddell |
genre |
Antarc* Antarctic Antarctica David Glacier Ice Sheet Ice Shelf The Cryosphere Victoria Land |
genre_facet |
Antarc* Antarctic Antarctica David Glacier Ice Sheet Ice Shelf The Cryosphere Victoria Land |
op_source |
The Cryosphere, Vol 15, Pp 5447-5471 (2021) |
op_relation |
https://tc.copernicus.org/articles/15/5447/2021/tc-15-5447-2021.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-15-5447-2021 1994-0416 1994-0424 https://doaj.org/article/5e25dbbfc8784b6f8c75fde9e169d87a |
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 |
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