A sub-centennial, Little Ice Age climate reconstruction using beetle subfossil data from Nunalleq, southwestern Alaska

• Published in: Quaternary International
• Main Authors: Forbes, Véronique, Ledger, Paul, Cretu, Denisa, Elias, Scott
• Other Authors: De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Memorial University of Newfoundland = Université Memorial de Terre-Neuve St. John's, Canada (MUN), Department of Archaeology, University of Aberdeen, University of Aberdeen, Department of Geography, Royal Holloway, Royal Holloway University of London (RHUL), Institute of Arctic Alpine Research University of Colorado Boulder (INSTAAR), University of Colorado Boulder, This research was funded through an Arts and Humanities Research Council grant (AH/K006029/1) awarded to Drs. Rick Knecht, Charlotta Hillerdal and Kate Britton, the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 703322 awarded to Dr. Véronique Forbes, and two NERC Radiocarbon Facility grants (NF/2015/1/6 and NF/2015/2/3) awarded to Drs. Rick Knecht and Paul Ledger., European Project: 703322,H2020,H2020-MSCA-IF-2015,WARFLY(2016)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: Little ice age; Alaska; Yup'ik; Mutual climatic range; Palaeoclimate; Coleoptera; [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; The ''Y''; Yukon; Kuskokwim
• Online Access: https://hal.archives-ouvertes.fr/hal-02280483; https://hal.archives-ouvertes.fr/hal-02280483/document; https://hal.archives-ouvertes.fr/hal-02280483/file/1-s2.0-S1040618219301089-main.pdf; https://doi.org/10.1016/j.quaint.2019.07.011

International audience There is myriad evidence that global warming is exerting a profoundly disruptive influence on the lifeways of modern native (Yup'ik) communities living in the Yukon-Kuskokwim (Y-K) delta of southwestern Alaska. Yup'ik subsistence is intimately tied to seasonal change and the ability to accurately predict the availability of plant and animal resources. It therefore seems reasonable to suggest that periods of climatic instability such as the Little Ice Age (LIA) may have had a deleterious effect on Yup'ik communities in the past. However, at present there are no palaeotemperature records that document the localised climatic changes of the last millennium in the Y-K Delta region. This lack of data hinders our understanding of the archaeological record from the site of Nunalleq, which is situated at the heart of the delta and was occupied during the LIA. To address this oversight, this paper presents the results of a Coleoptera (beetle) based climate reconstruction from a peat profile in the vicinity of Nunalleq to investigate the magnitude of Late Holocene climatic changes. Using the Mutual Climatic Range (MCR) method, we reconstruct mean summer and winter temperatures from the mid-15th to late-19th centuries. The results indicate that the past environments of Nunalleq were characterised by a climate significantly cooler than the present. The earliest definitive evidence for Little Ice Age cooling dates from the late 16th century, when mean summer temperatures were at least 1.2ᵒC below the modern mean. Temperatures appear to have remained lower than modern until the early 19th century. The coolest Nunalleq record – 1.3ᵒC below the modern mean summer temperatures – is centred on AD 1815, after which there is evidence for climatic amelioration. These data present differences with observations from other regions of Alaska and underline the importance of more local palaeoclimate reconstructions, particularly when interrogating the relationships between past climatic and social change.