Timing of the neoglacial onset on the North-Eastern Antarctic Peninsula based on lacustrine archive from Lake Anonima, Vega Island

• Published in: Global and Planetary Change
• Main Authors: Cejka, Tomas, Nyvlt, Daniel, Kopalova, Katerina, Bulinova, Marie, Kavan, Jan, Lirio, Juan M., Coria, Silvia H., Van de Vijver, Bart
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Economics; Physics; Antarctic; Antarctic Peninsula; Beak Island; Ross Island; The Antarctic; Vega Island; Antarc*; Ice cap; ice core; James Ross Island
• Online Access: https://hdl.handle.net/10067/1666070151162165141; https://repository.uantwerpen.be/docstore/d:irua:418

Abstract: To understand the complexity of the climate patterns in the Holocene, it is necessary to build detailed chronologies that provide a holistic picture of the individual climate periods occurring in the polar regions. In this regard, here we present a completely new, C-14-dated and synchronised multi-proxy chronology from the Lake Ananima (Vega Island, north-eastern Antarctic Peninsula) that provides a unique insight into the Late Holocene environment. In particular, we aim to interpret the substantial environmental and climatic change between the mid-late Holocene Hypsithermal and Neoglacial periods using various geochemical (total organic carbon, X-ray fluorescence spectroscopy), petrophysical (magnetic susceptibility, laser granulometry) and biological (diatom biostratigraphy) proxies. The termination of the mid-late Holocene Hypsithermal, characterised by overall warmer climate with favourable conditions for biogenic productivity, is followed by the regional-scale Neoglacial period, distinctive by the onset of climate deterioration, decreased siliciclastic input, suppressed biogenic (diatom) productivity and low organic content. Based on a principal component analysis, a multi-proxy record provides the precise timing of the Neoglacial onset in the Lake Anonima record at 2050 (2 sigma: 1990-2130) cal. yrs BP. Applying an adjacent and correlative ice-core (James Ross Island ice cap, r = 0.42), as well as a composite lake sediment (Beak Island, r = 0.49) chronologies, our research provides a refined timing of the Neoglacial onset for the north-eastern Antarctic Peninsula, which is determined to be 2070 +/- 50 yrs. BP. Moreover, the Neoglacial onset was compared with other studies from respective parts of the Antarctic Peninsula.