| Registro completo |
| Provedor de dados: |
5
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| País: |
France
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| Título: |
Sea surface temperature reconstructions over the last 70kyr off Portugal: Biomarker data and regional modeling
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| Autores: |
Darfeuil, Sophie
Menot, Guillemette
Giraud, Xavier
Rostek, Frauke
Tachikawa, Kazuyo
Garcia, Marta
Bard, Edouard
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| Data: |
2016-01
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| Ano: |
2016
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| Palavras-chave: |
Uk'37
TEX86
Iberian Margin
ROMS simulations
Modeled temperature proxy
SST
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| Resumo: |
This study aims at providing robust temperature reconstructions for a key oceanographic setting in the North Atlantic and at understanding the nature of the temperature signal recorded by the two biomarkers U-37(k) and TEX86, considering season and depth of production. To do so, high-resolution signals of U-37(k) and TEX86 are determined for the last 70kyr for core MD95-2042, located off Portugal. Signals of U-37(k) and TEX86 present a tight correlation, demonstrating a dominant temperature effect. U-37(k) signals correspond well to the annual mean sea surface temperature (SST), whereas TEX86H-derived temperatures are 5.6 degrees C higher, which is unrealistically warm for this area. Unsuitable TEX86 global linear calibrations on the Iberian Margin may suggest a possible occurrence of archaeal communities with specific temperature response. To assess the impact of different season or depth of production of the biomarkers on the recorded temperature in the sediment, modeled temperature proxies (Tproxies) are introduced in a Regional Oceanic Modeling System and tested for different seasons (annual/summer/winter) and depths (surface and 0-200m) of production for three climate modes (Present Day (PD), Last Glacial Maximum (LGM), and Heinrich Stadials (HS)). Similar temperature amplitudes between climate modes are found at MD95-2042 core site for observations, for both biomarkers, and for modeled annual surface production Tproxy: 5.5-7 degrees C for T(PD-LGM) and 3-4 degrees C for T(LGM-HS). Therefore, we propose a new TEX86H regional calibration to reconstruct present and past annual mean SSTs on the Iberian Margin.
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| Tipo: |
Text
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| Idioma: |
Inglês
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| Identificador: |
https://archimer.ifremer.fr/doc/00421/53288/54207.pdf
https://archimer.ifremer.fr/doc/00421/53288/54245.pdf
https://archimer.ifremer.fr/doc/00421/53288/54246.xls
DOI:10.1002/2015PA002831
https://archimer.ifremer.fr/doc/00421/53288/
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| Editor: |
Amer Geophysical Union
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| Relação: |
info:eu-repo/grantAgreement/EC/FP7/243908/EU//PAST4FUTURE
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| Formato: |
application/pdf
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| Fonte: |
Paleoceanography (0883-8305) (Amer Geophysical Union), 2016-01 , Vol. 31 , N. 1 , P. 40-65
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| Direitos: |
2015. American Geophysical Union. All rights reserved.
info:eu-repo/semantics/openAccess
restricted use
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