Climate fluctuations during the Holocene in NW Iberia: high and low latitude linkages
International audience High resolution benthic foraminiferal oxygen and carbon stable isotopes (? 18 O, ? 13 C) from core EUGC-3B are used here to infer rapid climatic changes for the last 8500 yr in the Ría de Muros (NW Iberian Margin). Benthic foraminiferal ? 18 O and ? 13 C potentially register m...
Main Authors: | , , , , |
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Other Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2007
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Subjects: | |
Online Access: | https://hal.science/hal-00298311 https://hal.science/hal-00298311/document https://hal.science/hal-00298311/file/cpd-3-1283-2007.pdf |
Summary: | International audience High resolution benthic foraminiferal oxygen and carbon stable isotopes (? 18 O, ? 13 C) from core EUGC-3B are used here to infer rapid climatic changes for the last 8500 yr in the Ría de Muros (NW Iberian Margin). Benthic foraminiferal ? 18 O and ? 13 C potentially register migrations in the position of the hydrographic front formed between two different intermediate water masses: Eastern North Atlantic Central Water of subpolar origin (ENACW sp ), and subtropical origin (ENACW sp ). The isotopic records have been compared with two well established North Atlantic marine Holocene paleoceanographic records from low (Sea Surface Temperatures anomalies off Cape Blanc, NW Africa) and high latitudes (Hematite Stained Grains percentage, subpolar North Atlantic). This comparison clearly demonstrates that there is a strong link between high- and low-latitude climatic perturbations at centennial-millennial time scales during the Holocene. Spectral analyses also points at a pole-to-equator propagation of the so-called 1500 yr cycles. Our results demonstrate that during the Holocene, the NW Iberian Margin has undergone a series of cold episodes which are likely triggered at high latitudes in the North Atlantic and are rapidly propagated towards lower latitudes. Conceivably, the propagation of these rapid climatic changes involves a shift of atmospheric and oceanic circulatory systems and so a migration of the hydrographical fronts and water masses all along the North Atlantic area. |
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