| Registro completo |
| Provedor de dados: |
ArchiMer
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| País: |
France
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| Título: |
Coherent Response of Antarctic Intermediate Water and Atlantic Meridional Overturning Circulation During the Last Deglaciation: Reconciling Contrasting Neodymium Isotope Reconstructions From the Tropical Atlantic
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| Autores: |
Gu, Sifan
Liu, Zhengyu
Zhang, Jiaxu
Rempfer, Johannes
Joos, Fortunat
Oppo, Delia W.
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| Data: |
2017-10
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| Ano: |
2017
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| Palavras-chave: |
AAIW
AMOC
Deglacial
Neodymium isotope
Paleocirculation tracer
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| Resumo: |
Antarctic Intermediate Water (AAIW) plays important roles in the global climate system and the global ocean nutrient and carbon cycles. However, it is unclear how AAIW responds to global climate changes. In particular, neodymium isotopic composition (epsilon(Nd)) reconstructions from different locations from the tropical Atlantic have led to a debate on the relationship between northward penetration of AAIW into the tropical Atlantic and the Atlantic meridional overturning circulation (AMOC) variability during the last deglaciation. We resolve this controversy by studying the transient oceanic evolution during the last deglaciation using a neodymium-enabled ocean model. Our results suggest a coherent response of AAIW and AMOC: when AMOC weakens, the northward penetration and transport of AAIW decrease while its depth and thickness increase. Our study highlights that as part of the return flow of the North Atlantic Deep Water, the northward penetration of AAIW in the Atlantic is determined predominately by AMOC intensity. Moreover, the inconsistency among different tropical Atlantic epsilon(Nd) reconstructions is reconciled by considering their corresponding core locations and depths, which were influenced by different water masses in the past. The very radiogenic water from the bottom of the Gulf of Mexico and the Caribbean Sea, which was previously overlooked in the interpretations of deglacial epsilon(Nd) variability, can be transported to shallow layers during active AMOC and modulates epsilon(Nd) in the tropical Atlantic. Changes in the AAIW core depth must also be considered. Thus, interpretation of epsilon(Nd) reconstructions from the tropical Atlantic is more complicated than suggested in previous studies.
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| Tipo: |
Text
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| Idioma: |
Inglês
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| Identificador: |
https://archimer.ifremer.fr/doc/00495/60709/65334.pdf
https://archimer.ifremer.fr/doc/00495/60709/65335.pdf
DOI:10.1002/2017PA003092
https://archimer.ifremer.fr/doc/00495/60709/
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| Editor: |
Amer Geophysical Union
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| Formato: |
application/pdf
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| Fonte: |
Paleoceanography (0883-8305) (Amer Geophysical Union), 2017-10 , Vol. 32 , N. 10 , P. 1036-1053
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| Direitos: |
info:eu-repo/semantics/openAccess
restricted use
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