Heterogeneous melting near the Thwaites Glacier grounding line
Thwaites Glacier represents 15% of the ice discharge from the West Antarctic Ice Sheet and influences a wider catchment(1–3). Because it is grounded below sea level(4,5), Thwaites Glacier is thought to be susceptible to runaway retreat triggered at the grounding line (GL) at which the glacier reache...
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Online Access: | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9931587/ http://www.ncbi.nlm.nih.gov/pubmed/36792738 https://doi.org/10.1038/s41586-022-05691-0 |
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ftpubmed:oai:pubmedcentral.nih.gov:9931587 2023-05-15T13:38:47+02:00 Heterogeneous melting near the Thwaites Glacier grounding line Schmidt, B. E. Washam, P. Davis, P. E. D. Nicholls, K. W. Holland, D. M. Lawrence, J. D. Riverman, K. L. Smith, J. A. Spears, A. Dichek, D. J. G. Mullen, A. D. Clyne, E. Yeager, B. Anker, P. Meister, M. R. Hurwitz, B. C. Quartini, E. S. Bryson, F. E. Basinski-Ferris, A. Thomas, C. Wake, J. Vaughan, D. G. Anandakrishnan, S. Rignot, E. Paden, J. Makinson, K. 2023-02-15 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9931587/ http://www.ncbi.nlm.nih.gov/pubmed/36792738 https://doi.org/10.1038/s41586-022-05691-0 en eng Nature Publishing Group UK http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9931587/ http://www.ncbi.nlm.nih.gov/pubmed/36792738 http://dx.doi.org/10.1038/s41586-022-05691-0 © The Author(s), under exclusive licence to Springer Nature Limited 2023 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . CC-BY Nature Article Text 2023 ftpubmed https://doi.org/10.1038/s41586-022-05691-0 2023-02-19T02:16:04Z Thwaites Glacier represents 15% of the ice discharge from the West Antarctic Ice Sheet and influences a wider catchment(1–3). Because it is grounded below sea level(4,5), Thwaites Glacier is thought to be susceptible to runaway retreat triggered at the grounding line (GL) at which the glacier reaches the ocean(6,7). Recent ice-flow acceleration(2,8) and retreat of the ice front(8–10) and GL(11,12) indicate that ice loss will continue. The relative impacts of mechanisms underlying recent retreat are however uncertain. Here we show sustained GL retreat from at least 2011 to 2020 and resolve mechanisms of ice-shelf melt at the submetre scale. Our conclusions are based on observations of the Thwaites Eastern Ice Shelf (TEIS) from an underwater vehicle, extending from the GL to 3 km oceanward and from the ice–ocean interface to the sea floor. These observations show a rough ice base above a sea floor sloping upward towards the GL and an ocean cavity in which the warmest water exceeds 2 °C above freezing. Data closest to the ice base show that enhanced melting occurs along sloped surfaces that initiate near the GL and evolve into steep-sided terraces. This pronounced melting along steep ice faces, including in crevasses, produces stratification that suppresses melt along flat interfaces. These data imply that slope-dependent melting sculpts the ice base and acts as an important response to ocean warming. Text Antarc* Antarctic Ice Sheet Ice Shelf Thwaites Glacier PubMed Central (PMC) Antarctic Thwaites Glacier ENVELOPE(-106.750,-106.750,-75.500,-75.500) West Antarctic Ice Sheet Nature 614 7948 471 478 |
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Article Schmidt, B. E. Washam, P. Davis, P. E. D. Nicholls, K. W. Holland, D. M. Lawrence, J. D. Riverman, K. L. Smith, J. A. Spears, A. Dichek, D. J. G. Mullen, A. D. Clyne, E. Yeager, B. Anker, P. Meister, M. R. Hurwitz, B. C. Quartini, E. S. Bryson, F. E. Basinski-Ferris, A. Thomas, C. Wake, J. Vaughan, D. G. Anandakrishnan, S. Rignot, E. Paden, J. Makinson, K. Heterogeneous melting near the Thwaites Glacier grounding line |
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Article |
description |
Thwaites Glacier represents 15% of the ice discharge from the West Antarctic Ice Sheet and influences a wider catchment(1–3). Because it is grounded below sea level(4,5), Thwaites Glacier is thought to be susceptible to runaway retreat triggered at the grounding line (GL) at which the glacier reaches the ocean(6,7). Recent ice-flow acceleration(2,8) and retreat of the ice front(8–10) and GL(11,12) indicate that ice loss will continue. The relative impacts of mechanisms underlying recent retreat are however uncertain. Here we show sustained GL retreat from at least 2011 to 2020 and resolve mechanisms of ice-shelf melt at the submetre scale. Our conclusions are based on observations of the Thwaites Eastern Ice Shelf (TEIS) from an underwater vehicle, extending from the GL to 3 km oceanward and from the ice–ocean interface to the sea floor. These observations show a rough ice base above a sea floor sloping upward towards the GL and an ocean cavity in which the warmest water exceeds 2 °C above freezing. Data closest to the ice base show that enhanced melting occurs along sloped surfaces that initiate near the GL and evolve into steep-sided terraces. This pronounced melting along steep ice faces, including in crevasses, produces stratification that suppresses melt along flat interfaces. These data imply that slope-dependent melting sculpts the ice base and acts as an important response to ocean warming. |
format |
Text |
author |
Schmidt, B. E. Washam, P. Davis, P. E. D. Nicholls, K. W. Holland, D. M. Lawrence, J. D. Riverman, K. L. Smith, J. A. Spears, A. Dichek, D. J. G. Mullen, A. D. Clyne, E. Yeager, B. Anker, P. Meister, M. R. Hurwitz, B. C. Quartini, E. S. Bryson, F. E. Basinski-Ferris, A. Thomas, C. Wake, J. Vaughan, D. G. Anandakrishnan, S. Rignot, E. Paden, J. Makinson, K. |
author_facet |
Schmidt, B. E. Washam, P. Davis, P. E. D. Nicholls, K. W. Holland, D. M. Lawrence, J. D. Riverman, K. L. Smith, J. A. Spears, A. Dichek, D. J. G. Mullen, A. D. Clyne, E. Yeager, B. Anker, P. Meister, M. R. Hurwitz, B. C. Quartini, E. S. Bryson, F. E. Basinski-Ferris, A. Thomas, C. Wake, J. Vaughan, D. G. Anandakrishnan, S. Rignot, E. Paden, J. Makinson, K. |
author_sort |
Schmidt, B. E. |
title |
Heterogeneous melting near the Thwaites Glacier grounding line |
title_short |
Heterogeneous melting near the Thwaites Glacier grounding line |
title_full |
Heterogeneous melting near the Thwaites Glacier grounding line |
title_fullStr |
Heterogeneous melting near the Thwaites Glacier grounding line |
title_full_unstemmed |
Heterogeneous melting near the Thwaites Glacier grounding line |
title_sort |
heterogeneous melting near the thwaites glacier grounding line |
publisher |
Nature Publishing Group UK |
publishDate |
2023 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9931587/ http://www.ncbi.nlm.nih.gov/pubmed/36792738 https://doi.org/10.1038/s41586-022-05691-0 |
long_lat |
ENVELOPE(-106.750,-106.750,-75.500,-75.500) |
geographic |
Antarctic Thwaites Glacier West Antarctic Ice Sheet |
geographic_facet |
Antarctic Thwaites Glacier West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf Thwaites Glacier |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf Thwaites Glacier |
op_source |
Nature |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9931587/ http://www.ncbi.nlm.nih.gov/pubmed/36792738 http://dx.doi.org/10.1038/s41586-022-05691-0 |
op_rights |
© The Author(s), under exclusive licence to Springer Nature Limited 2023 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1038/s41586-022-05691-0 |
container_title |
Nature |
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614 |
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7948 |
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471 |
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478 |
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