| Registro completo |
| Provedor de dados: |
ArchiMer
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| País: |
France
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| Título: |
A role for icebergs in the 8.2 ka climate event
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| Autores: |
Wiersma, Ane P.
Jongma, Jochem I.
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| Data: |
2010-08
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| Ano: |
2010
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| Palavras-chave: |
8.2 ka event
Climate modeling
Icebergs
Laurentide ice sheet
Hudson Strait
Holocene
Heinrich events
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| Resumo: |
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.
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| Tipo: |
Text
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| Idioma: |
Inglês
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| Identificador: |
https://archimer.ifremer.fr/doc/00496/60749/65152.pdf
DOI:10.1007/s00382-009-0645-1
https://archimer.ifremer.fr/doc/00496/60749/
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| Editor: |
Springer
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| Formato: |
application/pdf
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| Fonte: |
Climate Dynamics (0930-7575) (Springer), 2010-08 , Vol. 35 , N. 2-3 , P. 535-549
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| Direitos: |
info:eu-repo/semantics/openAccess
restricted use
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