A role for icebergs in the 8.2 ka climate event
We investigate the potential role of icebergs in the 8.2 ka climate event, using a coupled climate model equipped with an iceberg component. First, we evaluate the effect of a large iceberg discharge originating from the decaying Laurentide ice sheet on ocean circulation, compared to a release of an...
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ftarchimer:oai:archimer.ifremer.fr:60749 2023-05-15T16:30:01+02:00 A role for icebergs in the 8.2 ka climate event Wiersma, Ane P. Jongma, Jochem I. 2010-08 application/pdf https://archimer.ifremer.fr/doc/00496/60749/65152.pdf https://doi.org/10.1007/s00382-009-0645-1 https://archimer.ifremer.fr/doc/00496/60749/ eng eng Springer https://archimer.ifremer.fr/doc/00496/60749/65152.pdf doi:10.1007/s00382-009-0645-1 https://archimer.ifremer.fr/doc/00496/60749/ info:eu-repo/semantics/openAccess restricted use Climate Dynamics (0930-7575) (Springer), 2010-08 , Vol. 35 , N. 2-3 , P. 535-549 8.2 ka event Climate modeling Icebergs Laurentide ice sheet Hudson Strait Holocene Heinrich events text Publication info:eu-repo/semantics/article 2010 ftarchimer https://doi.org/10.1007/s00382-009-0645-1 2021-09-23T20:32:46Z We investigate the potential role of icebergs in the 8.2 ka climate event, using a coupled climate model equipped with an iceberg component. First, we evaluate the effect of a large iceberg discharge originating from the decaying Laurentide ice sheet on ocean circulation, compared to a release of an identical volume of freshwater alone. Our results show that, on top of the freshwater effect, a large iceberg discharge facilitates sea-ice growth as a result of lower sea-surface temperatures induced by latent heat of melting. This causes an 8% increased sea-ice cover, 5% stronger reduction in North Atlantic Deep Water production and 1A degrees C lower temperature in Greenland. Second, we use the model to investigate the effect of a hypothetical two-stage lake drainage, which is suggested by several investigators to have triggered the 8.2 ka climate event. To account for the final collapse of the ice-dam holding the Laurentide Lakes we accompany the secondary freshwater pulse in one scenario with a fast 5-year iceberg discharge and in a second scenario with a slow 100-year iceberg discharge. Our experiments show that a two-stage lake drainage accompanied by the collapsing ice-dam could explain the anomalies observed around the 8.2 ka climate event in various climate records. In addition, they advocate a potential role for icebergs in the 8.2 ka climate event and illustrate the importance of latent heat of melting in the simulation of climate events that involve icebergs. Our two-stage lake drainage experiments provide a framework in the discussion of two-stage lake drainage and ice sheet collapse. Article in Journal/Newspaper Greenland Hudson Strait Ice Sheet North Atlantic Deep Water North Atlantic Sea ice Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Greenland Hudson Hudson Strait ENVELOPE(-70.000,-70.000,62.000,62.000) Climate Dynamics 35 2-3 535 549 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
topic |
8.2 ka event Climate modeling Icebergs Laurentide ice sheet Hudson Strait Holocene Heinrich events |
spellingShingle |
8.2 ka event Climate modeling Icebergs Laurentide ice sheet Hudson Strait Holocene Heinrich events Wiersma, Ane P. Jongma, Jochem I. A role for icebergs in the 8.2 ka climate event |
topic_facet |
8.2 ka event Climate modeling Icebergs Laurentide ice sheet Hudson Strait Holocene Heinrich events |
description |
We investigate the potential role of icebergs in the 8.2 ka climate event, using a coupled climate model equipped with an iceberg component. First, we evaluate the effect of a large iceberg discharge originating from the decaying Laurentide ice sheet on ocean circulation, compared to a release of an identical volume of freshwater alone. Our results show that, on top of the freshwater effect, a large iceberg discharge facilitates sea-ice growth as a result of lower sea-surface temperatures induced by latent heat of melting. This causes an 8% increased sea-ice cover, 5% stronger reduction in North Atlantic Deep Water production and 1A degrees C lower temperature in Greenland. Second, we use the model to investigate the effect of a hypothetical two-stage lake drainage, which is suggested by several investigators to have triggered the 8.2 ka climate event. To account for the final collapse of the ice-dam holding the Laurentide Lakes we accompany the secondary freshwater pulse in one scenario with a fast 5-year iceberg discharge and in a second scenario with a slow 100-year iceberg discharge. Our experiments show that a two-stage lake drainage accompanied by the collapsing ice-dam could explain the anomalies observed around the 8.2 ka climate event in various climate records. In addition, they advocate a potential role for icebergs in the 8.2 ka climate event and illustrate the importance of latent heat of melting in the simulation of climate events that involve icebergs. Our two-stage lake drainage experiments provide a framework in the discussion of two-stage lake drainage and ice sheet collapse. |
format |
Article in Journal/Newspaper |
author |
Wiersma, Ane P. Jongma, Jochem I. |
author_facet |
Wiersma, Ane P. Jongma, Jochem I. |
author_sort |
Wiersma, Ane P. |
title |
A role for icebergs in the 8.2 ka climate event |
title_short |
A role for icebergs in the 8.2 ka climate event |
title_full |
A role for icebergs in the 8.2 ka climate event |
title_fullStr |
A role for icebergs in the 8.2 ka climate event |
title_full_unstemmed |
A role for icebergs in the 8.2 ka climate event |
title_sort |
role for icebergs in the 8.2 ka climate event |
publisher |
Springer |
publishDate |
2010 |
url |
https://archimer.ifremer.fr/doc/00496/60749/65152.pdf https://doi.org/10.1007/s00382-009-0645-1 https://archimer.ifremer.fr/doc/00496/60749/ |
long_lat |
ENVELOPE(-70.000,-70.000,62.000,62.000) |
geographic |
Greenland Hudson Hudson Strait |
geographic_facet |
Greenland Hudson Hudson Strait |
genre |
Greenland Hudson Strait Ice Sheet North Atlantic Deep Water North Atlantic Sea ice |
genre_facet |
Greenland Hudson Strait Ice Sheet North Atlantic Deep Water North Atlantic Sea ice |
op_source |
Climate Dynamics (0930-7575) (Springer), 2010-08 , Vol. 35 , N. 2-3 , P. 535-549 |
op_relation |
https://archimer.ifremer.fr/doc/00496/60749/65152.pdf doi:10.1007/s00382-009-0645-1 https://archimer.ifremer.fr/doc/00496/60749/ |
op_rights |
info:eu-repo/semantics/openAccess restricted use |
op_doi |
https://doi.org/10.1007/s00382-009-0645-1 |
container_title |
Climate Dynamics |
container_volume |
35 |
container_issue |
2-3 |
container_start_page |
535 |
op_container_end_page |
549 |
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1766019732903821312 |