Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation
International audience The last glacial termination was a key event during Earth’s Quaternary history that was associated with rapid, high-magnitude environmental and climatic change. Identifying its trigger mechanisms is critical for understanding Earth’s modern climate system over millennial times...
Published in: | Frontiers in Earth Science |
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Main Authors: | , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2021
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Online Access: | https://hal.science/hal-03420208 https://hal.science/hal-03420208/document https://hal.science/hal-03420208/file/Leger%20et%20al.%202021%20Patagonia_End%20of%20Last%20glaciation.pdf https://doi.org/10.3389/feart.2021.751987 |
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ftunivaixmarseil:oai:HAL:hal-03420208v1 |
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openpolar |
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Open Polar |
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Aix-Marseille Université: HAL |
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language |
English |
topic |
Patagonia glaciers and climate last glacial termination cosmogenic nuclide surface exposure dating glacier modelling southern westerly winds Quaternary palaeoclimates [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology |
spellingShingle |
Patagonia glaciers and climate last glacial termination cosmogenic nuclide surface exposure dating glacier modelling southern westerly winds Quaternary palaeoclimates [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology Leger, Tancrède, P M Hein, Andrew, S Goldberg, Daniel Schimmelpfennig, Irene van Wyk de Vries, Maximillian, S Bingham, Robert, G Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation |
topic_facet |
Patagonia glaciers and climate last glacial termination cosmogenic nuclide surface exposure dating glacier modelling southern westerly winds Quaternary palaeoclimates [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology |
description |
International audience The last glacial termination was a key event during Earth’s Quaternary history that was associated with rapid, high-magnitude environmental and climatic change. Identifying its trigger mechanisms is critical for understanding Earth’s modern climate system over millennial timescales. It has been proposed that latitudinal shifts of the Southern Hemisphere Westerly Wind belt and the coupled Subtropical Front are important components of the changes leading to global deglaciation, making them essential to investigate and reconstruct empirically. The Patagonian Andes are part of the only continental landmass that fully intersects the Southern Westerly Winds, and thus present an opportunity to study their former latitudinal migrations through time and to constrain southern mid-latitude palaeo-climates. Here we use a combination of geomorphological mapping, terrestrial cosmogenic nuclide exposure dating and glacial numerical modelling to reconstruct the late-Last Glacial Maximum (LGM) behaviour and surface mass balance of two mountain glaciers of northeastern Patagonia (43°S, 71°W), the El Loro and Río Comisario palaeo-glaciers. In both valleys, we find geomorphological evidence of glacier advances that occurred after the retreat of the main ice-sheet outlet glacier from its LGM margins. We date the outermost moraine in the El Loro valley to 18.0 ± 1.15 ka. Moreover, a series of moraine-matching simulations were run for both glaciers using a spatially-distributed ice-flow model coupled with a positive degree-day surface mass balance parameterisation. Following a correction for cumulative local surface uplift resulting from glacial isostatic adjustment since ∼18 ka, which we estimate to be ∼130 m, the glacier model suggests that regional mean annual temperatures were between 1.9 and 2.8°C lower than present at around 18.0 ± 1.15 ka, while precipitation was between ∼50 and ∼380% higher than today. Our findings support the proposed equatorward migration of the precipitation-bearing Southern ... |
author2 |
School of Geosciences Edinburgh University of Edinburgh (Edin.) Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) University of Minnesota Twin Cities (UMN) University of Minnesota System (UMN) |
format |
Article in Journal/Newspaper |
author |
Leger, Tancrède, P M Hein, Andrew, S Goldberg, Daniel Schimmelpfennig, Irene van Wyk de Vries, Maximillian, S Bingham, Robert, G |
author_facet |
Leger, Tancrède, P M Hein, Andrew, S Goldberg, Daniel Schimmelpfennig, Irene van Wyk de Vries, Maximillian, S Bingham, Robert, G |
author_sort |
Leger, Tancrède, P M |
title |
Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation |
title_short |
Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation |
title_full |
Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation |
title_fullStr |
Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation |
title_full_unstemmed |
Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation |
title_sort |
northeastern patagonian glacier advances (43°s) reflect northward migration of the southern westerlies towards the end of the last glaciation |
publisher |
HAL CCSD |
publishDate |
2021 |
url |
https://hal.science/hal-03420208 https://hal.science/hal-03420208/document https://hal.science/hal-03420208/file/Leger%20et%20al.%202021%20Patagonia_End%20of%20Last%20glaciation.pdf https://doi.org/10.3389/feart.2021.751987 |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
ISSN: 2296-6463 Frontiers in Earth Science https://hal.science/hal-03420208 Frontiers in Earth Science, 2021, 9, pp.751987. ⟨10.3389/feart.2021.751987⟩ https://www.frontiersin.org/articles/10.3389/feart.2021.751987/full |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3389/feart.2021.751987 hal-03420208 https://hal.science/hal-03420208 https://hal.science/hal-03420208/document https://hal.science/hal-03420208/file/Leger%20et%20al.%202021%20Patagonia_End%20of%20Last%20glaciation.pdf doi:10.3389/feart.2021.751987 WOS: 000733723600001 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.3389/feart.2021.75198710.3389/feart.2021.751987/full |
container_title |
Frontiers in Earth Science |
container_volume |
9 |
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1799481922281275392 |
spelling |
ftunivaixmarseil:oai:HAL:hal-03420208v1 2024-05-19T07:42:15+00:00 Northeastern Patagonian Glacier Advances (43°S) Reflect Northward Migration of the Southern Westerlies Towards the End of the Last Glaciation Leger, Tancrède, P M Hein, Andrew, S Goldberg, Daniel Schimmelpfennig, Irene van Wyk de Vries, Maximillian, S Bingham, Robert, G School of Geosciences Edinburgh University of Edinburgh (Edin.) Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) University of Minnesota Twin Cities (UMN) University of Minnesota System (UMN) 2021 https://hal.science/hal-03420208 https://hal.science/hal-03420208/document https://hal.science/hal-03420208/file/Leger%20et%20al.%202021%20Patagonia_End%20of%20Last%20glaciation.pdf https://doi.org/10.3389/feart.2021.751987 en eng HAL CCSD Frontiers Media info:eu-repo/semantics/altIdentifier/doi/10.3389/feart.2021.751987 hal-03420208 https://hal.science/hal-03420208 https://hal.science/hal-03420208/document https://hal.science/hal-03420208/file/Leger%20et%20al.%202021%20Patagonia_End%20of%20Last%20glaciation.pdf doi:10.3389/feart.2021.751987 WOS: 000733723600001 info:eu-repo/semantics/OpenAccess ISSN: 2296-6463 Frontiers in Earth Science https://hal.science/hal-03420208 Frontiers in Earth Science, 2021, 9, pp.751987. ⟨10.3389/feart.2021.751987⟩ https://www.frontiersin.org/articles/10.3389/feart.2021.751987/full Patagonia glaciers and climate last glacial termination cosmogenic nuclide surface exposure dating glacier modelling southern westerly winds Quaternary palaeoclimates [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology info:eu-repo/semantics/article Journal articles 2021 ftunivaixmarseil https://doi.org/10.3389/feart.2021.75198710.3389/feart.2021.751987/full 2024-04-25T00:48:45Z International audience The last glacial termination was a key event during Earth’s Quaternary history that was associated with rapid, high-magnitude environmental and climatic change. Identifying its trigger mechanisms is critical for understanding Earth’s modern climate system over millennial timescales. It has been proposed that latitudinal shifts of the Southern Hemisphere Westerly Wind belt and the coupled Subtropical Front are important components of the changes leading to global deglaciation, making them essential to investigate and reconstruct empirically. The Patagonian Andes are part of the only continental landmass that fully intersects the Southern Westerly Winds, and thus present an opportunity to study their former latitudinal migrations through time and to constrain southern mid-latitude palaeo-climates. Here we use a combination of geomorphological mapping, terrestrial cosmogenic nuclide exposure dating and glacial numerical modelling to reconstruct the late-Last Glacial Maximum (LGM) behaviour and surface mass balance of two mountain glaciers of northeastern Patagonia (43°S, 71°W), the El Loro and Río Comisario palaeo-glaciers. In both valleys, we find geomorphological evidence of glacier advances that occurred after the retreat of the main ice-sheet outlet glacier from its LGM margins. We date the outermost moraine in the El Loro valley to 18.0 ± 1.15 ka. Moreover, a series of moraine-matching simulations were run for both glaciers using a spatially-distributed ice-flow model coupled with a positive degree-day surface mass balance parameterisation. Following a correction for cumulative local surface uplift resulting from glacial isostatic adjustment since ∼18 ka, which we estimate to be ∼130 m, the glacier model suggests that regional mean annual temperatures were between 1.9 and 2.8°C lower than present at around 18.0 ± 1.15 ka, while precipitation was between ∼50 and ∼380% higher than today. Our findings support the proposed equatorward migration of the precipitation-bearing Southern ... Article in Journal/Newspaper Ice Sheet Aix-Marseille Université: HAL Frontiers in Earth Science 9 |