Stalagmite-inferred hydroclimate changes in northern Italy during Allerød/Younger Dryas transition
- 1Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan (jerry16787@gmail.com)
- 2High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), Department of Geosciences, National Taiwan University, Taipei 10617, Taiwan (hsunming.hu@gmail.com, river@ntu.edu.tw)
- 3Research Center for Future Earth, National Taiwan University, Taipei 10617, Taiwan
- 4CEPAM—Cultures et Environnements Préhistoire, Antiquité, Moyen Âge, CNRS, Université Côte d’Azur, 06300 Nice, France (veronique.michel@cepam.cnrs.fr)
- 5Laboratoire Géoazur, OCA, CNRS, IRD, Université Côte d’Azur, 06560 Valbonne, France
- 6HNHP, UMR 7194, MNHN, CNRS, UPMC, UPVD, Sorbonne Universités, 75013 Paris, France (pvalensi06@gmail.com)
- 7Musée de Préhistoire, 06690 Tourrette-Levens, France
- 8Department of Civilizations and Forms of Knowledge, University of Pisa, Via dei Mille 19, 56126 Pisa, Italy (elisabetta.starnini@unipi.it)
- 9Archaeological Superintendency of Liguria, Via Balbi 10, 16126 Genova, Italy
- 10Toirano Cave, Piazzale D. Maineri 1, 17055 Toirano, Italy; martazunino@tiscali.it
The Younger Dryas (YD), a 1200-year-long cooling event interrupting the warm Bølling-Allerød period, started from 12,870 ± 30 yr BP (2σ, before 1950 C.E.). Here we present decadal-resolved stalagmite BA18-2 multi-proxy records from Bàsura cave, northern Italy. The StalAge age-depth model with 8 U-Th dates with 2-sigma errors of ± 26-193 yrs shows that BA18-2 encompasses Allerød/YD transition, from 14,038 ± 92 to 12,090 ± 54 yr BP. Oxygen isotope data fluctuate between -7.16‰ and -3.68‰, with a clear 2.4‰ increase during the YD onset at 12,870 ± 30 yr BP. Stalagmite BA18-2 Sr/Ca and Ba/Ca linger from 0.060-0.085 mmol/mol and 6.4-9.1 µmol/mol, respectively, from 14,038 ± 92 to 12,681 ± 55 yr BP, ~ 2 centuries after the beginning of YD. A clear 160-year-long two-step increase in both Sr/Ca and Ba/Ca records started from 12,681 ± 55 yr BP, which is a 200-yr lag relative to the timing of BA18-2 oxygen isotope increasing trend. We argue that the oxygen isotope could be governed by temperature, moisture source, and/or rainfall amount; while, the Sr/Ca and Ba/Ca ratios predominantly reflect precipitation change. Our results might suggest asynchronous thermal and hydrological changes in northern Italy during the Allerøod/YD transition.
How to cite: Hsieh, C.-J., Hu, H.-M., Shen, C.-C., Michel, V., Valensi, P., Starnini, E., and Zunino, M.: Stalagmite-inferred hydroclimate changes in northern Italy during Allerød/Younger Dryas transition, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-4748, https://doi.org/10.5194/egusphere-egu23-4748, 2023.
