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| Vanniere, B.; Magny, M.; Joannin, S.; Simonneau, A.; Wirth, S. B.; Hamann, Y.; Chapron, E.; Gilli, A.; Desmet, M.; Anselmetti, F. S.. |
| Two lacustrine sediment cores from Lake Ledro in northern Italy were studied to produce chronologies of flood events for the past 10 000 yr. For this purpose, we have developed an automatic method that objectively identifies the sedimentary imprint of river floods in the downstream lake basin. The method was based on colour data extracted from processed core photographs, and the count data were analysed to capture the flood signal. Flood frequency and reconstructed sedimentary dynamics were compared with lakelevel changes and pollen inferred vegetation dynamics. The results suggest a record marked by low flood frequency during the early and middle Holocene (10 000-4500 cal BP). Only modest increases during short intervals are recorded at ca. 8000, 7500,... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00181/29200/27587.pdf |
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| Debret, M.; Bout-roumazeilles, V.; Grousset, F.; Desmet, M.; Mcmanus, J. F.; Massei, N.; Sebag, D.; Petit, J. -r.; Copard, Y.; Trentesaux, A.. |
| Since the first suggestion of 1500-year cycles in the advance and retreat of glaciers (Denton and Karlen, 1973), many studies have uncovered evidence of repeated climate oscillations of 2500, 1500, and 1000 years. During last glacial period, natural climate cycles of 1500 years appear to be persistent (Bond and Lotti, 1995) and remarkably regular (Mayewski et al., 1997; Rahmstorf, 2003), yet the origin of this pacing during the Holocene remains a mystery (Rahmstorf, 2003), making it one of the outstanding puzzles of climate variability. Solar variability is often considered likely to be responsible for such cyclicities, but the evidence for solar forcing is difficult to evaluate within available data series due to the shortcomings of conventional... |
| Tipo: Text |
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| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00233/34454/32880.pdf |
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