Stalagmite-inferred European westerly drift in the early Weichselian with centennial-scale variability in marine isotope stage 5a
International audience The Weichselian glaciation is characterized by significant ocean circulation variations starting from ∼115 thousand years ago (ka) and terminating at ∼11.5 ka. The early Weichselian (115–74 ka), especially marine isotope stage (MIS) 5a at 85–74 ka, provides a window for unders...
Published in: | Quaternary Science Reviews |
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Main Authors: | , , , , , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2022
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Subjects: | |
Online Access: | https://hal.science/hal-03687628 https://hal.science/hal-03687628/document https://hal.science/hal-03687628/file/JQSR-D-21-00661.pdf https://doi.org/10.1016/j.quascirev.2022.107581 |
Summary: | International audience The Weichselian glaciation is characterized by significant ocean circulation variations starting from ∼115 thousand years ago (ka) and terminating at ∼11.5 ka. The early Weichselian (115–74 ka), especially marine isotope stage (MIS) 5a at 85–74 ka, provides a window for understanding the linkage between the European westerlies and Mediterranean climate. However, lack of highly-resolved paleoclimate records with absolute chronologies hampers our knowledge of decadal-to-centennial-scale climate changes and forcings in the circum-Mediterranean realm. Here, we present 230Th-dated stalagmite-inferred hydroclimate records from Observatoire cave (43°44′ N, 7°25’ E), Monaco, for the period between 88.7 ± 0.4 and 80.3 ± 0.1 ka, covering portions of MIS 5b and 5a. Agreement between Observatoire and circum-Mediterranean stalagmite records confirm large-scale warming over the Atlantic-Europe territory during the transition from MIS 5b to 5a. Subdecadally-resolved Observatoire δ18O and δ13C records express four multi-centennial arid intervals in southern Europe at 84–80 ka in the first-half of MIS 5a, suggesting centennial westerly drifts, a finding supported by a model simulation. Westerly changes and associated arid events can be attributed to slowdowns of the Atlantic meridional overturning circulation, North Atlantic Oscillation states, and solar activity. |
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