Temperature and precipitation regime in LGM human refugia of southwestern Europe inferred from δ 13 C and δ 18 O of large mammal remains

• Published in: Quaternary Science Reviews
• Main Authors: Lécuyer, Christophe, Hillaire-Marcel, Claude, Burke, Ariane, Julien, Marie-Anne, Hélie, Jean-François
• Other Authors: Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), 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)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: Last glacial; Temperature; Precipitation; Stable isotopes; Apatite; Mammals; Western europe; [SDU]Sciences of the Universe [physics]; North Atlantic
• Online Access: https://insu.hal.science/insu-03710147; https://insu.hal.science/insu-03710147/document; https://insu.hal.science/insu-03710147/file/S0277379121000032.pdf; https://doi.org/10.1016/j.quascirev.2021.106796

International audience The climate shift of the Last Glacial Maximum (LGM) strongly impacted the vegetation cover and related trophic chains of western Europe. Harsh, cold and dry conditions then prevailed in most regions, strongly impacting migrations and survival of human beings. Nonetheless, environments suitable for mammalian fauna to survive persisted in SW Europe thus providing refugia for hunters. Tooth enamel from large herbivorous mammal remains from archaeological sites located in southwest France and Spain were analyzed for their stable carbon and oxygen isotope compositions for documenting paleotemperatures and paleoprecipitations. These sites were occupied by humans between 25 ky and 16 ky. Skeletal remains of Cervidae, Equidae and Caprinae suggest colder and drier conditions relative to present-day. Paleoprecipitations were reconstructed from a modern-based transfer function using δ 13 C-values of apatite carbonate, then corrected for the low atmospheric pCO 2 value of the LGM. They ranged from ≈250 mm yr -1 on the Mediterranean façade, to ≈550 mm yr -1 on the Atlantic side. Setting the δ 18 O-value of the northeastern North Atlantic LGM-surface water to +0.8‰, based on Biscay Golf marine core studies, mean air temperatures inferred from 18 O-data in apatite calcite were close to 14-15 °C (Mediterranean) and 6 °C-10 °C (Atlantic), i.e., about 4-5 °C and 5-8 °C higher than pre-industrial temperatures, respectively. The two areas thus define distinct clusters of air temperatures and precipitation regimes with strong negative offsets vs the Present. These isotopically-reconstructed climate conditions indicate a strong control from proximal surface ocean/marine waters, in particular of mean annual air temperatures.