| Registro completo |
| Provedor de dados: |
ArchiMer
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| País: |
France
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| Título: |
Atlantic forcing of Western Mediterranean winter rain minima during the last 12,000 years
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| Autores: |
Zielhofer, Christoph
Fletcher, William J.
Mischke, Steffen
De Batist, Marc
Campbell, Jennifer F. E.
Joannin, Sebastien
Tjallingii, Rik
El Hamouti, Najib
Junginger, Annett
Stele, Andreas
Bussmann, Jens
Schneider, Birgit
Lauer, Tobias
Spitzer, Katrin
Strupler, Michael
Brachert, Thomas
Mikdad, Abdeslam
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| Data: |
2017-02
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| Ano: |
2017
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| Palavras-chave: |
Holocene
Younger Dryas
Winter rain minima
Atlantic forcing
Western Mediterranean
North Atlantic Oscillation (NAO)
Seasonality
Solar forcing
Lake sediments
Middle Atlas
Morocco
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| Resumo: |
The limited availability of high-resolution continuous archives, insufficient chronological control, and complex hydro-climatic forcing mechanisms lead to many uncertainties in palaeo-hydrological reconstructions for the Western Mediterranean. In this study we present a newly recovered 19.63 m long core from Lake Sidi Ali in the North African Middle Atlas, a transition zone of Atlantic, Western Mediterranean and Saharan air mass trajectories. With a multi-proxy approach based on magnetic susceptibility, carbonate and total organic C content: core-scanning and quantitative XRF, stable isotopes of ostracod shells, charcoal counts, Cedrus pollen abundance, and a first set of diatom data, we reconstruct Western Mediterranean hydro-climatic variability, seasonality and forcing mechanisms during the last 12,000 yr. A robust chronological model based on AMS C-14 dated pollen concentrates supports our high resolution multi-proxy study. Long-term trends reveal low lake levels at the end of the Younger Dryas, during the mid-Holocene interval 6.6 to 5.4 cal ka BP, and during the last 3000 years. In contrast, lake levels are mostly high during the Early and Mid-Holocene. The record also shows sub-millennial- to centennial-scale decreases in Western Mediterranean winter rain at 11.4, 10.3, 9.2, 8.2, 7.2, 6.6, 6.0, 5.4, 5.0, 4.4, 3.5, 2.9, 2.2, 1.9, 1.7, 1.5, 1.0, 0.7, and 0.2 cal ka BP. Early Holocene winter rain minima are in phase with cooling events and millennial-scale meltwater discharges in the sub-polar North Atlantic. Our proxy parameters do not show so far a clear impact of Saharan air masses on Mediterranean hydro-climate in North Africa. However, a significant hydro-climatic shift at the end of the African Humid Period (-5 ka) indicates a change in climate forcing mechanisms. The Late Holocene climate variability in the Middle Atlas features a multi-centennial-scale NAO-type pattern, with Atlantic cooling and Western Mediterranean winter rain maxima generally associated with solar minima.
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| Tipo: |
Text
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| Idioma: |
Inglês
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| Identificador: |
https://archimer.ifremer.fr/doc/00420/53188/55016.pdf
https://archimer.ifremer.fr/doc/00420/53188/55017.pdf
DOI:10.1016/j.quascirev.2016.11.037
https://archimer.ifremer.fr/doc/00420/53188/
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| Editor: |
Pergamon-elsevier Science Ltd
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| Formato: |
application/pdf
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| Fonte: |
Quaternary Science Reviews (0277-3791) (Pergamon-elsevier Science Ltd), 2017-02 , Vol. 157 , P. 29-51
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| Direitos: |
2016 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
info:eu-repo/semantics/openAccess
restricted use
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