Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland
To date the final stage in deglaciation of the Greenland shelf, when a contiguous ice sheet margin on the inner shelf transitioned to outlet glaciers in troughs with intervening ice-free areas, we generated cosmogenic 10 Be dates from bedrock knobs on six outlying islands along a stretch of 300 km o...
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ftdoajarticles:oai:doaj.org/article:aac0aecf562f48f59a90c83b6a928a12 2023-05-15T16:23:44+02:00 Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland S. Funder A. H. L. Sørensen N. K. Larsen A. A. Bjørk J. P. Briner J. Olsen A. Schomacker L. B. Levy K. H. Kjær 2021-03-01T00:00:00Z https://doi.org/10.5194/cp-17-587-2021 https://doaj.org/article/aac0aecf562f48f59a90c83b6a928a12 EN eng Copernicus Publications https://cp.copernicus.org/articles/17/587/2021/cp-17-587-2021.pdf https://doaj.org/toc/1814-9324 https://doaj.org/toc/1814-9332 doi:10.5194/cp-17-587-2021 1814-9324 1814-9332 https://doaj.org/article/aac0aecf562f48f59a90c83b6a928a12 Climate of the Past, Vol 17, Pp 587-601 (2021) Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 article 2021 ftdoajarticles https://doi.org/10.5194/cp-17-587-2021 2022-12-31T13:31:21Z To date the final stage in deglaciation of the Greenland shelf, when a contiguous ice sheet margin on the inner shelf transitioned to outlet glaciers in troughs with intervening ice-free areas, we generated cosmogenic 10 Be dates from bedrock knobs on six outlying islands along a stretch of 300 km of the southwestern Greenland coast. Despite 10 Be inheritance influencing some dates, the ages generally support a Greenland Ice Sheet (GrIS) margin that retreated off the inner shelf during the middle Younger Dryas (YD) period. Published 10 Be- and 14 C-dated records show that this history of the GrIS margin is seen in other parts of Greenland but with large variations in the extent and speed of retreat, sometimes even between neighbouring areas. Areas with a chronology extending into the Allerød period show no marked ice margin change at the Allerød–YD transition except in northernmost Greenland. In contrast, landforms on the shelf (moraines and grounding zone wedges) have been suggested to indicate YD readvances or long-lasting ice margin stillstands on the middle shelf. However, these features have been dated primarily by correlation with cold periods in the ice core temperature records. Ice margin retreat during the middle and late YD is explained by advection of warm subsurface water at the ice margin and by increased seasonality. Our results therefore point to the complexity of the climate–ice margin relation and to the urgent need for direct dating of the early deglaciation history of Greenland. Article in Journal/Newspaper Greenland ice core Ice Sheet Directory of Open Access Journals: DOAJ Articles Greenland Climate of the Past 17 2 587 601 |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
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English |
topic |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 |
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Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 S. Funder A. H. L. Sørensen N. K. Larsen A. A. Bjørk J. P. Briner J. Olsen A. Schomacker L. B. Levy K. H. Kjær Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland |
topic_facet |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 |
description |
To date the final stage in deglaciation of the Greenland shelf, when a contiguous ice sheet margin on the inner shelf transitioned to outlet glaciers in troughs with intervening ice-free areas, we generated cosmogenic 10 Be dates from bedrock knobs on six outlying islands along a stretch of 300 km of the southwestern Greenland coast. Despite 10 Be inheritance influencing some dates, the ages generally support a Greenland Ice Sheet (GrIS) margin that retreated off the inner shelf during the middle Younger Dryas (YD) period. Published 10 Be- and 14 C-dated records show that this history of the GrIS margin is seen in other parts of Greenland but with large variations in the extent and speed of retreat, sometimes even between neighbouring areas. Areas with a chronology extending into the Allerød period show no marked ice margin change at the Allerød–YD transition except in northernmost Greenland. In contrast, landforms on the shelf (moraines and grounding zone wedges) have been suggested to indicate YD readvances or long-lasting ice margin stillstands on the middle shelf. However, these features have been dated primarily by correlation with cold periods in the ice core temperature records. Ice margin retreat during the middle and late YD is explained by advection of warm subsurface water at the ice margin and by increased seasonality. Our results therefore point to the complexity of the climate–ice margin relation and to the urgent need for direct dating of the early deglaciation history of Greenland. |
format |
Article in Journal/Newspaper |
author |
S. Funder A. H. L. Sørensen N. K. Larsen A. A. Bjørk J. P. Briner J. Olsen A. Schomacker L. B. Levy K. H. Kjær |
author_facet |
S. Funder A. H. L. Sørensen N. K. Larsen A. A. Bjørk J. P. Briner J. Olsen A. Schomacker L. B. Levy K. H. Kjær |
author_sort |
S. Funder |
title |
Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland |
title_short |
Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland |
title_full |
Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland |
title_fullStr |
Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland |
title_full_unstemmed |
Younger Dryas ice margin retreat in Greenland: new evidence from southwestern Greenland |
title_sort |
younger dryas ice margin retreat in greenland: new evidence from southwestern greenland |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/cp-17-587-2021 https://doaj.org/article/aac0aecf562f48f59a90c83b6a928a12 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland ice core Ice Sheet |
genre_facet |
Greenland ice core Ice Sheet |
op_source |
Climate of the Past, Vol 17, Pp 587-601 (2021) |
op_relation |
https://cp.copernicus.org/articles/17/587/2021/cp-17-587-2021.pdf https://doaj.org/toc/1814-9324 https://doaj.org/toc/1814-9332 doi:10.5194/cp-17-587-2021 1814-9324 1814-9332 https://doaj.org/article/aac0aecf562f48f59a90c83b6a928a12 |
op_doi |
https://doi.org/10.5194/cp-17-587-2021 |
container_title |
Climate of the Past |
container_volume |
17 |
container_issue |
2 |
container_start_page |
587 |
op_container_end_page |
601 |
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1766011981257506816 |