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| Darfeuil, Sophie; Menot, Guillemette; Giraud, Xavier; Rostek, Frauke; Tachikawa, Kazuyo; Garcia, Marta; Bard, Edouard. |
| 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... |
| Tipo: Text |
Palavras-chave: Uk'37; TEX86; Iberian Margin; ROMS simulations; Modeled temperature proxy; SST. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00421/53288/54207.pdf |
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| Bard, Edouard; Menot, Guillemette; Rostek, Frauke; Licari, Laetitia; Boening, Philipp; Edwards, R. Lawrence; Cheng, Hai; Wang, Yongjin; Heaton, Timothy J.. |
| We present a new record of radiocarbon ages measured by accelerator mass spectrometry (AMS) on a deep-sea core collected off the Pakistan Margin. The C-14 ages measured on the planktonic foraminifera Globigerinoides ruber from core MD04-2876 define a high and stable sedimentation rate on the order of 50 cm/kyr over the last 50 kyr. The site is distant from the main upwelling zone of the western Arabian Sea where C-14 reservoir age is large and may be variable. Many independent proxies based on elemental analyses, mineralogy, biomarkers, isotopic proxies, and foraminiferal abundances show abrupt changes correlative with Dansgaard-Oeschger and Heinrich events. It is now common knowledge that these climatic events also affected the Arabian Sea during the last... |
| Tipo: Text |
Palavras-chave: Berian Margin; Pakistan Margin; 14C; Calibration. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00264/37569/35852.pdf |
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| Soulet, Guillaume; Menot, Guillemette; Bayon, Germain; Rostek, Frauke; Ponzevera, Emmanuel; Toucanne, Samuel; Lericolais, Gilles; Bard, Edouard. |
| Continental ice sheets are a key component of the Earth’s climate system, but their internal dynamics need to be further studied. Since the last deglaciation, the northern Eurasian Fennoscandian Ice Sheet (FIS) has been connected to the Black Sea (BS) watershed, making this basin a suitable location to investigate former ice-sheet dynamics. Here, from a core retrieved in the BS, we combine the use of neodymium isotopes, high-resolution elemental analysis, and biomarkers to trace changes in sediment provenance and river runoff. We reveal cyclic releases of meltwater originating from Lake Disna, a proglacial lake linked to the FIS during Heinrich Stadial 1. Regional interactions within the climate–lake–FIS system, linked to changes in the availability of... |
| Tipo: Text |
Palavras-chave: Ice dynamics; Meltwater routing; European hydrographic network. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00134/24489/22516.pdf |
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| Menot, Guillemette; Bard, Edouard. |
| Climatic models simulate abrupt oscillations that are associated, in the North Atlantic, with Dansgaard-Oeschger and Heinrich events. However, the geographic extension of temperature anomalies is largely uncontrolled due to the scarcity of quantitative records of sufficient time resolution on the European continent. Here, we propose, based on a recently developed temperature proxy (TEX86), a reconstruction of millennial-scale temperature variations in a Black Sea sediment archive for the last 40,000 years. Prior to any paleoclimatological interpretations the effects of potential bias, such as seasonality and depth of maximum export production on temperature reconstructions, are considered for the Black Sea. Based on previous work, a tentative method for... |
| Tipo: Text |
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| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00140/25124/23232.pdf |
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| Soulet, Guillaume; Menot, Guillemette; Garreta, Vincent; Rostek, Frauke; Zaragosi, Sebastien; Lericolais, Gilles; Bard, Edouard. |
| Chronologies of sediments that document the last glacial history of the Black Sea "Lake" are hampered by issues relating to reservoir age. Regulated by basin hydrology, reservoir ages represent a tool that could potentially be used to better understand the response of Black Sea "Lake" hydrology to climate change. Therefore, deciphering reservoir age evolution is crucial both for better constraining the basin chronological framework and for providing new insights into our understanding of Black Sea "Lake" hydrology. By tuning a meaningful new high-resolution geochemical dataset (obtained from core MD04-2790) to a climate reference record, here, we propose a reliable chronology spanning the last 32 kyr BP. The chronology is compared to a large AMS... |
| Tipo: Text |
Palavras-chave: Black Sea; Reservoir age; Radiocarbon; Last Glacial; Last Deglaciation; Paleoclimate. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00043/15379/12817.pdf |
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