The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event
The so-called "8.2 ka event" is widely regarded as a major Holocene climate perturbation. It is most readily identifiable in the oxygen-isotope records from Greenland ice cores as an approximately 160-year-long cold interval between 8250 and 8090 years BP. The prevailing view has been that...
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ftdoajarticles:oai:doaj.org/article:7112d2e0235944ac9aaf90909a6725e3 2023-05-15T16:28:23+02:00 The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event A. D. Tegzes E. Jansen R. J. Telford 2014-10-01T00:00:00Z https://doi.org/10.5194/cp-10-1887-2014 https://doaj.org/article/7112d2e0235944ac9aaf90909a6725e3 EN eng Copernicus Publications http://www.clim-past.net/10/1887/2014/cp-10-1887-2014.pdf https://doaj.org/toc/1814-9324 https://doaj.org/toc/1814-9332 1814-9324 1814-9332 doi:10.5194/cp-10-1887-2014 https://doaj.org/article/7112d2e0235944ac9aaf90909a6725e3 Climate of the Past, Vol 10, Iss 5, Pp 1887-1904 (2014) Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 article 2014 ftdoajarticles https://doi.org/10.5194/cp-10-1887-2014 2022-12-31T04:00:07Z The so-called "8.2 ka event" is widely regarded as a major Holocene climate perturbation. It is most readily identifiable in the oxygen-isotope records from Greenland ice cores as an approximately 160-year-long cold interval between 8250 and 8090 years BP. The prevailing view has been that the cooling over Greenland, and potentially over the northern North Atlantic at least, was triggered by the catastrophic final drainage of the Agassiz–Ojibway proglacial lake as part of the remnant Laurentide Ice Sheet collapsed over Hudson Bay at around 8420 ± 80 years BP. The consequent freshening of surface waters in the northern North Atlantic Ocean and the Nordic Seas resulted in weaker overturning, and hence reduced northward ocean heat transport. We have reconstructed variations in the strength of the eastern branch of the Atlantic Inflow into the Nordic Seas around the time of the lake outbursts. While the initial freshwater forcing may have been even larger than originally thought, as the lake outbursts may have been accompanied by a major iceberg discharge from Hudson Bay, our proxy records from the mid-Norwegian Margin do not evidence a uniquely large slowdown in the eastern branch of the Atlantic Inflow at the time. Therefore, its main role in the 8.2 ka event may have been the (rapid) advection of fresh and cold waters to high northern latitudes, initiating rapid sea-ice expansion and an increase in surface albedo. Article in Journal/Newspaper Greenland Greenland ice cores Hudson Bay Ice Sheet Nordic Seas North Atlantic Sea ice Directory of Open Access Journals: DOAJ Articles Hudson Bay Greenland Hudson Climate of the Past 10 5 1887 1904 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 |
spellingShingle |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 A. D. Tegzes E. Jansen R. J. Telford The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event |
topic_facet |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 |
description |
The so-called "8.2 ka event" is widely regarded as a major Holocene climate perturbation. It is most readily identifiable in the oxygen-isotope records from Greenland ice cores as an approximately 160-year-long cold interval between 8250 and 8090 years BP. The prevailing view has been that the cooling over Greenland, and potentially over the northern North Atlantic at least, was triggered by the catastrophic final drainage of the Agassiz–Ojibway proglacial lake as part of the remnant Laurentide Ice Sheet collapsed over Hudson Bay at around 8420 ± 80 years BP. The consequent freshening of surface waters in the northern North Atlantic Ocean and the Nordic Seas resulted in weaker overturning, and hence reduced northward ocean heat transport. We have reconstructed variations in the strength of the eastern branch of the Atlantic Inflow into the Nordic Seas around the time of the lake outbursts. While the initial freshwater forcing may have been even larger than originally thought, as the lake outbursts may have been accompanied by a major iceberg discharge from Hudson Bay, our proxy records from the mid-Norwegian Margin do not evidence a uniquely large slowdown in the eastern branch of the Atlantic Inflow at the time. Therefore, its main role in the 8.2 ka event may have been the (rapid) advection of fresh and cold waters to high northern latitudes, initiating rapid sea-ice expansion and an increase in surface albedo. |
format |
Article in Journal/Newspaper |
author |
A. D. Tegzes E. Jansen R. J. Telford |
author_facet |
A. D. Tegzes E. Jansen R. J. Telford |
author_sort |
A. D. Tegzes |
title |
The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event |
title_short |
The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event |
title_full |
The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event |
title_fullStr |
The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event |
title_full_unstemmed |
The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka event |
title_sort |
role of the northward-directed (sub)surface limb of the atlantic meridional overturning circulation during the 8.2 ka event |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/cp-10-1887-2014 https://doaj.org/article/7112d2e0235944ac9aaf90909a6725e3 |
geographic |
Hudson Bay Greenland Hudson |
geographic_facet |
Hudson Bay Greenland Hudson |
genre |
Greenland Greenland ice cores Hudson Bay Ice Sheet Nordic Seas North Atlantic Sea ice |
genre_facet |
Greenland Greenland ice cores Hudson Bay Ice Sheet Nordic Seas North Atlantic Sea ice |
op_source |
Climate of the Past, Vol 10, Iss 5, Pp 1887-1904 (2014) |
op_relation |
http://www.clim-past.net/10/1887/2014/cp-10-1887-2014.pdf https://doaj.org/toc/1814-9324 https://doaj.org/toc/1814-9332 1814-9324 1814-9332 doi:10.5194/cp-10-1887-2014 https://doaj.org/article/7112d2e0235944ac9aaf90909a6725e3 |
op_doi |
https://doi.org/10.5194/cp-10-1887-2014 |
container_title |
Climate of the Past |
container_volume |
10 |
container_issue |
5 |
container_start_page |
1887 |
op_container_end_page |
1904 |
_version_ |
1766018020357963776 |