High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector
Understanding the past and future evolution of the Antarctic Ice Sheet is challenged by the availability and quality of observed paleo-boundary conditions. Numerical ice-sheet models often rely on these paleo-boundary conditions to guide and evaluate their models' predictions of sea-level rise,...
Published in: | The Cryosphere |
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Language: | English |
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European Geosciences Union
2023
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Online Access: | http://nora.nerc.ac.uk/id/eprint/533495/ https://nora.nerc.ac.uk/id/eprint/533495/1/tc-17-1497-2023.pdf https://tc.copernicus.org/articles/17/1497/2023/tc-17-1497-2023.html |
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ftnerc:oai:nora.nerc.ac.uk:533495 2023-06-11T04:06:17+02:00 High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector Bodart, Julien A. Bingham, Robert G. Young, Duncan A. MacGregor, Joseph A. Ashmore, David W. Quartini, Enrica Hein, Andrew S. Vaughan, David G. Blakenship, Donald D. 2023-04-06 text http://nora.nerc.ac.uk/id/eprint/533495/ https://nora.nerc.ac.uk/id/eprint/533495/1/tc-17-1497-2023.pdf https://tc.copernicus.org/articles/17/1497/2023/tc-17-1497-2023.html en eng European Geosciences Union https://nora.nerc.ac.uk/id/eprint/533495/1/tc-17-1497-2023.pdf Bodart, Julien A.; Bingham, Robert G.; Young, Duncan A.; MacGregor, Joseph A.; Ashmore, David W.; Quartini, Enrica; Hein, Andrew S.; Vaughan, David G. orcid:0000-0002-9065-0570 Blakenship, Donald D. 2023 High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector. The Cryosphere, 17 (4). 1497-1512. https://doi.org/10.5194/tc-17-1497-2023 <https://doi.org/10.5194/tc-17-1497-2023> cc_by_4 Publication - Article PeerReviewed 2023 ftnerc https://doi.org/10.5194/tc-17-1497-2023 2023-05-04T23:02:43Z Understanding the past and future evolution of the Antarctic Ice Sheet is challenged by the availability and quality of observed paleo-boundary conditions. Numerical ice-sheet models often rely on these paleo-boundary conditions to guide and evaluate their models' predictions of sea-level rise, with varying levels of confidence due to the sparsity of existing data across the ice sheet. A key data source for large-scale reconstruction of past ice-sheet processes are internal reflecting horizons (IRHs) detected by radio-echo sounding (RES). When IRHs are isochronal and dated at ice cores, they can be used to determine paleo-accumulation rates and patterns on large spatial scales. Using a spatially extensive IRH over the Pine Island Glacier (PIG), Thwaites Glacier (THW), and the Institute and Möller ice streams (IMIS, covering a total of 610 000 km2 or 30 % of the West Antarctic Ice Sheet (WAIS)), and a local layer approximation model, we infer mid-Holocene accumulation rates over the slow-flowing parts of these catchments for the past ∼4700 years. By comparing our results with modern climate reanalysis models (1979–2019) and observational syntheses (1651–2010), we estimate that accumulation rates over the Amundsen–Weddell–Ross Divide were on average 18 % higher during the mid-Holocene than modern rates. However, no significant spatial changes in the accumulation pattern were observed. The higher mid-Holocene accumulation-rate estimates match previous paleo-accumulation estimates from ice-core records and targeted RES surveys over the ice divide, and they also coincide with periods of grounding-line readvance during the Holocene over the Weddell and Ross sea sectors. We find that our spatially extensive, mid-Holocene-to-present accumulation estimates are consistent with a sustained late-Holocene period of higher accumulation rates occurring over millennia reconstructed from the WAIS Divide ice core (WD14), thus indicating that this ice core is spatially representative of the wider West Antarctic region. We conclude ... Article in Journal/Newspaper Antarc* Antarctic Antarctica ice core Ice Sheet Pine Island Pine Island Glacier Ross Sea The Cryosphere Thwaites Glacier West Antarctica Natural Environment Research Council: NERC Open Research Archive Antarctic Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Ross Sea The Antarctic Thwaites Glacier ENVELOPE(-106.750,-106.750,-75.500,-75.500) Weddell West Antarctic Ice Sheet West Antarctica The Cryosphere 17 4 1497 1512 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
Understanding the past and future evolution of the Antarctic Ice Sheet is challenged by the availability and quality of observed paleo-boundary conditions. Numerical ice-sheet models often rely on these paleo-boundary conditions to guide and evaluate their models' predictions of sea-level rise, with varying levels of confidence due to the sparsity of existing data across the ice sheet. A key data source for large-scale reconstruction of past ice-sheet processes are internal reflecting horizons (IRHs) detected by radio-echo sounding (RES). When IRHs are isochronal and dated at ice cores, they can be used to determine paleo-accumulation rates and patterns on large spatial scales. Using a spatially extensive IRH over the Pine Island Glacier (PIG), Thwaites Glacier (THW), and the Institute and Möller ice streams (IMIS, covering a total of 610 000 km2 or 30 % of the West Antarctic Ice Sheet (WAIS)), and a local layer approximation model, we infer mid-Holocene accumulation rates over the slow-flowing parts of these catchments for the past ∼4700 years. By comparing our results with modern climate reanalysis models (1979–2019) and observational syntheses (1651–2010), we estimate that accumulation rates over the Amundsen–Weddell–Ross Divide were on average 18 % higher during the mid-Holocene than modern rates. However, no significant spatial changes in the accumulation pattern were observed. The higher mid-Holocene accumulation-rate estimates match previous paleo-accumulation estimates from ice-core records and targeted RES surveys over the ice divide, and they also coincide with periods of grounding-line readvance during the Holocene over the Weddell and Ross sea sectors. We find that our spatially extensive, mid-Holocene-to-present accumulation estimates are consistent with a sustained late-Holocene period of higher accumulation rates occurring over millennia reconstructed from the WAIS Divide ice core (WD14), thus indicating that this ice core is spatially representative of the wider West Antarctic region. We conclude ... |
format |
Article in Journal/Newspaper |
author |
Bodart, Julien A. Bingham, Robert G. Young, Duncan A. MacGregor, Joseph A. Ashmore, David W. Quartini, Enrica Hein, Andrew S. Vaughan, David G. Blakenship, Donald D. |
spellingShingle |
Bodart, Julien A. Bingham, Robert G. Young, Duncan A. MacGregor, Joseph A. Ashmore, David W. Quartini, Enrica Hein, Andrew S. Vaughan, David G. Blakenship, Donald D. High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector |
author_facet |
Bodart, Julien A. Bingham, Robert G. Young, Duncan A. MacGregor, Joseph A. Ashmore, David W. Quartini, Enrica Hein, Andrew S. Vaughan, David G. Blakenship, Donald D. |
author_sort |
Bodart, Julien A. |
title |
High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector |
title_short |
High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector |
title_full |
High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector |
title_fullStr |
High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector |
title_full_unstemmed |
High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector |
title_sort |
high mid-holocene accumulation rates over west antarctica inferred from a pervasive ice-penetrating radar reflector |
publisher |
European Geosciences Union |
publishDate |
2023 |
url |
http://nora.nerc.ac.uk/id/eprint/533495/ https://nora.nerc.ac.uk/id/eprint/533495/1/tc-17-1497-2023.pdf https://tc.copernicus.org/articles/17/1497/2023/tc-17-1497-2023.html |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) ENVELOPE(-106.750,-106.750,-75.500,-75.500) |
geographic |
Antarctic Pine Island Glacier Ross Sea The Antarctic Thwaites Glacier Weddell West Antarctic Ice Sheet West Antarctica |
geographic_facet |
Antarctic Pine Island Glacier Ross Sea The Antarctic Thwaites Glacier Weddell West Antarctic Ice Sheet West Antarctica |
genre |
Antarc* Antarctic Antarctica ice core Ice Sheet Pine Island Pine Island Glacier Ross Sea The Cryosphere Thwaites Glacier West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica ice core Ice Sheet Pine Island Pine Island Glacier Ross Sea The Cryosphere Thwaites Glacier West Antarctica |
op_relation |
https://nora.nerc.ac.uk/id/eprint/533495/1/tc-17-1497-2023.pdf Bodart, Julien A.; Bingham, Robert G.; Young, Duncan A.; MacGregor, Joseph A.; Ashmore, David W.; Quartini, Enrica; Hein, Andrew S.; Vaughan, David G. orcid:0000-0002-9065-0570 Blakenship, Donald D. 2023 High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector. The Cryosphere, 17 (4). 1497-1512. https://doi.org/10.5194/tc-17-1497-2023 <https://doi.org/10.5194/tc-17-1497-2023> |
op_rights |
cc_by_4 |
op_doi |
https://doi.org/10.5194/tc-17-1497-2023 |
container_title |
The Cryosphere |
container_volume |
17 |
container_issue |
4 |
container_start_page |
1497 |
op_container_end_page |
1512 |
_version_ |
1768378158236565504 |