A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century
Understanding the history of the Greenland Ice Sheet (GrIS) is critical for determining its sensitivity to warming and contribution to sea level; however, that history is poorly known before the last interglacial. Most knowledge comes from interpretation of marine sediment, an indirect record of pas...
Published in: | Proceedings of the National Academy of Sciences |
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Online Access: | http://www.osti.gov/servlets/purl/1771446 https://www.osti.gov/biblio/1771446 https://doi.org/10.1073/pnas.2021442118 |
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ftosti:oai:osti.gov:1771446 2023-07-30T04:03:47+02:00 A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century Christ, Andrew J. Bierman, Paul R. Schaefer, Joerg M. Dahl-Jensen, Dorthe Steffensen, Jørgen P. Corbett, Lee B. Peteet, Dorothy M. Thomas, Elizabeth K. Steig, Eric J. Rittenour, Tammy M. Tison, Jean-Louis Blard, Pierre-Henri Perdrial, Nicolas Dethier, David P. Lini, Andrea Hidy, Alan J. Caffee, Marc W. Southon, John 2022-11-11 application/pdf http://www.osti.gov/servlets/purl/1771446 https://www.osti.gov/biblio/1771446 https://doi.org/10.1073/pnas.2021442118 unknown http://www.osti.gov/servlets/purl/1771446 https://www.osti.gov/biblio/1771446 https://doi.org/10.1073/pnas.2021442118 doi:10.1073/pnas.2021442118 58 GEOSCIENCES 2022 ftosti https://doi.org/10.1073/pnas.2021442118 2023-07-11T10:02:01Z Understanding the history of the Greenland Ice Sheet (GrIS) is critical for determining its sensitivity to warming and contribution to sea level; however, that history is poorly known before the last interglacial. Most knowledge comes from interpretation of marine sediment, an indirect record of past ice-sheet extent and behavior. Subglacial sediment and rock, retrieved at the base of ice cores, provide terrestrial evidence for GrIS behavior during the Pleistocene. Here, we use multiple methods to determine GrIS history from subglacial sediment at the base of the Camp Century ice core collected in 1966. This material contains a stratigraphic record of glaciation and vegetation in northwestern Greenland spanning the Pleistocene. Enriched stable isotopes of pore-ice suggest precipitation at lower elevations implying ice-sheet absence. Plant macrofossils and biomarkers in the sediment indicate that paleo-ecosystems from previous interglacial periods are preserved beneath the GrIS. Cosmogenic 26 Al/ 10 Be and luminescence data bracket the burial of the lower-most sediment between <3.2 ± 0.4 Ma and >0.7 to 1.4 Ma. In the upper-most sediment, cosmogenic 26 Al/ 10 Be data require exposure within the last 1.0 ± 0.1 My. The unique subglacial sedimentary record from Camp Century documents at least two episodes of ice-free, vegetated conditions, each followed by glaciation. The lower sediment derives from an Early Pleistocene GrIS advance. 26 Al/ 10 Be ratios in the upper-most sediment match those in subglacial bedrock from central Greenland, suggesting similar ice-cover histories across the GrIS. Here, we conclude that the GrIS persisted through much of the Pleistocene but melted and reformed at least once since 1.1 Ma. Other/Unknown Material Greenland ice core Ice Sheet SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Greenland Proceedings of the National Academy of Sciences 118 13 |
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Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
58 GEOSCIENCES |
spellingShingle |
58 GEOSCIENCES Christ, Andrew J. Bierman, Paul R. Schaefer, Joerg M. Dahl-Jensen, Dorthe Steffensen, Jørgen P. Corbett, Lee B. Peteet, Dorothy M. Thomas, Elizabeth K. Steig, Eric J. Rittenour, Tammy M. Tison, Jean-Louis Blard, Pierre-Henri Perdrial, Nicolas Dethier, David P. Lini, Andrea Hidy, Alan J. Caffee, Marc W. Southon, John A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century |
topic_facet |
58 GEOSCIENCES |
description |
Understanding the history of the Greenland Ice Sheet (GrIS) is critical for determining its sensitivity to warming and contribution to sea level; however, that history is poorly known before the last interglacial. Most knowledge comes from interpretation of marine sediment, an indirect record of past ice-sheet extent and behavior. Subglacial sediment and rock, retrieved at the base of ice cores, provide terrestrial evidence for GrIS behavior during the Pleistocene. Here, we use multiple methods to determine GrIS history from subglacial sediment at the base of the Camp Century ice core collected in 1966. This material contains a stratigraphic record of glaciation and vegetation in northwestern Greenland spanning the Pleistocene. Enriched stable isotopes of pore-ice suggest precipitation at lower elevations implying ice-sheet absence. Plant macrofossils and biomarkers in the sediment indicate that paleo-ecosystems from previous interglacial periods are preserved beneath the GrIS. Cosmogenic 26 Al/ 10 Be and luminescence data bracket the burial of the lower-most sediment between <3.2 ± 0.4 Ma and >0.7 to 1.4 Ma. In the upper-most sediment, cosmogenic 26 Al/ 10 Be data require exposure within the last 1.0 ± 0.1 My. The unique subglacial sedimentary record from Camp Century documents at least two episodes of ice-free, vegetated conditions, each followed by glaciation. The lower sediment derives from an Early Pleistocene GrIS advance. 26 Al/ 10 Be ratios in the upper-most sediment match those in subglacial bedrock from central Greenland, suggesting similar ice-cover histories across the GrIS. Here, we conclude that the GrIS persisted through much of the Pleistocene but melted and reformed at least once since 1.1 Ma. |
author |
Christ, Andrew J. Bierman, Paul R. Schaefer, Joerg M. Dahl-Jensen, Dorthe Steffensen, Jørgen P. Corbett, Lee B. Peteet, Dorothy M. Thomas, Elizabeth K. Steig, Eric J. Rittenour, Tammy M. Tison, Jean-Louis Blard, Pierre-Henri Perdrial, Nicolas Dethier, David P. Lini, Andrea Hidy, Alan J. Caffee, Marc W. Southon, John |
author_facet |
Christ, Andrew J. Bierman, Paul R. Schaefer, Joerg M. Dahl-Jensen, Dorthe Steffensen, Jørgen P. Corbett, Lee B. Peteet, Dorothy M. Thomas, Elizabeth K. Steig, Eric J. Rittenour, Tammy M. Tison, Jean-Louis Blard, Pierre-Henri Perdrial, Nicolas Dethier, David P. Lini, Andrea Hidy, Alan J. Caffee, Marc W. Southon, John |
author_sort |
Christ, Andrew J. |
title |
A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century |
title_short |
A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century |
title_full |
A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century |
title_fullStr |
A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century |
title_full_unstemmed |
A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century |
title_sort |
multimillion-year-old record of greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at camp century |
publishDate |
2022 |
url |
http://www.osti.gov/servlets/purl/1771446 https://www.osti.gov/biblio/1771446 https://doi.org/10.1073/pnas.2021442118 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland ice core Ice Sheet |
genre_facet |
Greenland ice core Ice Sheet |
op_relation |
http://www.osti.gov/servlets/purl/1771446 https://www.osti.gov/biblio/1771446 https://doi.org/10.1073/pnas.2021442118 doi:10.1073/pnas.2021442118 |
op_doi |
https://doi.org/10.1073/pnas.2021442118 |
container_title |
Proceedings of the National Academy of Sciences |
container_volume |
118 |
container_issue |
13 |
_version_ |
1772814882539831296 |