Stalagmite-inferred European westerly drift with centennial-scale variability in marine isotope stage 5a

• Main Authors: Chung, Yun-Chuan, Menviel, Laurie C., Marchionne, Arianna, Mii, Horng-Sheng, Michel, Véronique, Valensi, Patricia, Jiang, Xiuyang, Simon, Patrick, Rossoni-Notter, Elena, Moussous, Abdelkader, Seppä, Heikki, Chien, Yu-Tang, Wu, Chung Che, Hu, Hsun-Ming, Shen, Chuan-Chou
• Other Authors: High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), National Taiwan University Taiwan (NTU), UNIVERSITY OF HELSINKI DEPARTMENT OF GEOSCIENCES AND GEOGRAPHY HELSINKI FIN, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), CLIMATE CHANGE RESEARCH CENTRE UNIVERSITY OF NEW SOUTH WALES SYDNEY AUS, Department of Mathematics and Statistics, University of Helsinki, Helsingin yliopisto = Helsingfors universitet = University of Helsinki, National Taiwan Normal University (NTNU), Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud ), Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Fujian Normal University Fujian, Musée d'Anthropologie préhistorique de Monaco, Monaco, University of Helsinki, Finland, National Science and Technology Center for Disaster Reduction (NCDR), Department of Chemistry and Applied Biosciences ETH Zürich (D-CHAB), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology Zürich (ETH Zürich)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDU]Sciences of the Universe [physics]; [SHS]Humanities and Social Sciences; North Atlantic
• Online Access: https://hal.science/hal-04236991

International audience Marine isotope stage (MIS) 5a, a relatively warm period occurring 85-74 thousand years ago (ka, before AD 1950) during the last glacial, 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, 5-yr-resolved stalagmite δ18O and δ13C records from Observatoire Cave (43°44’N, 7°25’E), Monaco, northern Mediterranean, for the period 83.6-80.3 ka, indicating hydrological changes over the region in the first-half of MIS 5a. Multi-centennial arid intervals are recorded in both δ18O and δ13C speleothem records, some of which correspond to North Atlantic ice rafted detritus (IRD) events. A transient simulation of MIS 5a suggests that these arid events could be due to slowdowns of Atlantic Meridional Overturning Circulation (AMOC), with the poleward-migrated westerlies. One or two drought events during the time without significant temperature drops in the high-latitude North Atlantic could be attributed centennial positive-NAO-like states. Furthermore, a significant periodicity of 210 years, matching the De Vries-Suess solar cycle, suggests a possible solar influence on hydroclimate in southern Europe at MIS 5a.