Late-glacial chironomid-based temperature reconstructions for Lago Piccolo di Avigliana in the southwestern Alps (Italy)

• Published in: Palaeogeography, Palaeoclimatology, Palaeoecology
• Main Authors: Larocque, Isabelle, Finsinger, Walter
• Other Authors: Institut National de la Recherche Scientifique Québec (INRS), Institute of Plant Sciences, Universität Bern / University of Bern (UNIBE), Laboratory of Palaeobotany and Palynology, Universiteit Utrecht / Utrecht University Utrecht
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: Lateglacial; Temperature; Chironomids; Vegetation dynamics; pollen analysis; Italy; Europe; [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture; forestry; [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics; [SDV.BIBS]Life Sciences [q-bio]/Quantitative Methods [q-bio.QM]; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; [SDE.MCG]Environmental Sciences/Global Changes; [SDE.ES]Environmental Sciences/Environment and Society; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; NGRIP; Northern Sweden
• Online Access: https://hal.science/hal-01845800; https://doi.org/10.1016/j.palaeo.2007.10.021

International audience Chironomid headcapsules were used to reconstruct late glacial and early-Holocene summer temperatures at Lago Piccolo di Avigliana (LPA). Two training sets (northern Sweden, North America) were used to infer temperatures. The reconstructed patterns of temperature change agreed well with the GRIP and NGRIP δ18O records. Inferred temperatures were high during the Bølling (ca 19 °C), slowly decreased to ca 17.5 °C during the Allerød, reached lowest temperatures (ca 16 °C) during the Younger Dryas, and increased to ca. 18.5 °C during the Preboreal. The amplitudes of change at climate transitions (i.e. Oldest Dryas/Bølling: 3 °C, Allerød/Younger Dryas: 1.5 °C, and Younger Dryas/Preboreal: 2.5 °C) were smaller than in the northern Alps but similar to those recorded at another site in northeastern Italy. Our results suggest that (1) Allerød temperatures were higher in the southern Alps and (2) higher during the Preboreal (1 °C) than during the Allerød. These differences might provide an explanation for the different responses of terrestrial-vegetation to late glacial and early-Holocene climatic changes in the two regions. Other sites on both sides of the Alps should be studied to confirm these two hypotheses.