Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet
During the last glacial period, the Laurentide Ice Sheet (LIS) underwent episodes of rapid iceberg discharge, recorded in ocean sediments as “Heinrich events” (HEs). Two competing models attempt to describe the stimulus for HEs via either internal ice sheet oscillations or external ocean-climate sys...
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craaas:10.1126/sciadv.abp9329 2024-06-09T07:44:53+00:00 Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet Edwards, Graham H. Blackburn, Terrence Piccione, Gavin Tulaczyk, Slawek Miller, Gifford H. Sikes, Cosmo 2022 http://dx.doi.org/10.1126/sciadv.abp9329 https://www.science.org/doi/pdf/10.1126/sciadv.abp9329 en eng American Association for the Advancement of Science (AAAS) Science Advances volume 8, issue 42 ISSN 2375-2548 journal-article 2022 craaas https://doi.org/10.1126/sciadv.abp9329 2024-05-16T12:55:24Z During the last glacial period, the Laurentide Ice Sheet (LIS) underwent episodes of rapid iceberg discharge, recorded in ocean sediments as “Heinrich events” (HEs). Two competing models attempt to describe the stimulus for HEs via either internal ice sheet oscillations or external ocean-climate system forcing. We present a terrestrial record of HEs from the northeastern LIS that strongly supports ocean-climate forcing. Subglacial carbonate precipitates from Baffin Island record episodes of subglacial melting coincident with the three most recent HEs, resulting from acceleration of nearby marine-terminating ice streams. Synchronized ice stream acceleration over Baffin Island and Hudson Strait is inconsistent with internal ice sheet oscillations alone and indicates a shared ocean-climate stimulus to coordinate these different glaciological systems. Isotopic compositions of these precipitates record widespread subglacial groundwater connectivity beneath the LIS. Extensive basal melting and flushing of these aquifers during the last HE may have been a harbinger for terminal deglaciation. Article in Journal/Newspaper Baffin Island Baffin Hudson Strait Ice Sheet AAAS Resource Center (American Association for the Advancement of Science) Baffin Island Hudson Hudson Strait ENVELOPE(-70.000,-70.000,62.000,62.000) Science Advances 8 42 |
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Open Polar |
collection |
AAAS Resource Center (American Association for the Advancement of Science) |
op_collection_id |
craaas |
language |
English |
description |
During the last glacial period, the Laurentide Ice Sheet (LIS) underwent episodes of rapid iceberg discharge, recorded in ocean sediments as “Heinrich events” (HEs). Two competing models attempt to describe the stimulus for HEs via either internal ice sheet oscillations or external ocean-climate system forcing. We present a terrestrial record of HEs from the northeastern LIS that strongly supports ocean-climate forcing. Subglacial carbonate precipitates from Baffin Island record episodes of subglacial melting coincident with the three most recent HEs, resulting from acceleration of nearby marine-terminating ice streams. Synchronized ice stream acceleration over Baffin Island and Hudson Strait is inconsistent with internal ice sheet oscillations alone and indicates a shared ocean-climate stimulus to coordinate these different glaciological systems. Isotopic compositions of these precipitates record widespread subglacial groundwater connectivity beneath the LIS. Extensive basal melting and flushing of these aquifers during the last HE may have been a harbinger for terminal deglaciation. |
format |
Article in Journal/Newspaper |
author |
Edwards, Graham H. Blackburn, Terrence Piccione, Gavin Tulaczyk, Slawek Miller, Gifford H. Sikes, Cosmo |
spellingShingle |
Edwards, Graham H. Blackburn, Terrence Piccione, Gavin Tulaczyk, Slawek Miller, Gifford H. Sikes, Cosmo Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet |
author_facet |
Edwards, Graham H. Blackburn, Terrence Piccione, Gavin Tulaczyk, Slawek Miller, Gifford H. Sikes, Cosmo |
author_sort |
Edwards, Graham H. |
title |
Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet |
title_short |
Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet |
title_full |
Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet |
title_fullStr |
Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet |
title_full_unstemmed |
Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet |
title_sort |
terrestrial evidence for ocean forcing of heinrich events and subglacial hydrologic connectivity of the laurentide ice sheet |
publisher |
American Association for the Advancement of Science (AAAS) |
publishDate |
2022 |
url |
http://dx.doi.org/10.1126/sciadv.abp9329 https://www.science.org/doi/pdf/10.1126/sciadv.abp9329 |
long_lat |
ENVELOPE(-70.000,-70.000,62.000,62.000) |
geographic |
Baffin Island Hudson Hudson Strait |
geographic_facet |
Baffin Island Hudson Hudson Strait |
genre |
Baffin Island Baffin Hudson Strait Ice Sheet |
genre_facet |
Baffin Island Baffin Hudson Strait Ice Sheet |
op_source |
Science Advances volume 8, issue 42 ISSN 2375-2548 |
op_doi |
https://doi.org/10.1126/sciadv.abp9329 |
container_title |
Science Advances |
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8 |
container_issue |
42 |
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1801373723782021120 |