Radiometric 81Kr dating identifies 120,000-year-old ice at Taylor Glacier, Antarctica

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Buizert, Christo, Baggenstos, Daniel, Jiang, Wei, Purtschert, Roland, Petrenko, Vasilii V., Lu, Zheng-Tian, Müller, Peter, Kuhl, Tanner, Lee, James, Severinghaus, Jeffrey P., Brook, Edward J.
• Format: Text
• Language: English
• Published: National Academy of Sciences 2014
• Subjects: Physical Sciences; Taylor Glacier; Antarc*; Antarctica; ice core
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4024921; http://www.ncbi.nlm.nih.gov/pubmed/24753606; https://doi.org/10.1073/pnas.1320329111

Past variations in Earth’s climate and atmospheric composition are recorded in accumulating polar meteoric ice and the air trapped within it. Ice outcrops provide accessible archives of old ice but are difficult to date reliably. Here we demonstrate 81Kr radiometric dating of ice, allowing accurate dating of up to 1.5 million-year-old ice. The technique successfully identifies valuable ice from the previous interglacial period at Taylor Glacier, Antarctica. Our method will enhance the scientific value of outcropping sites as archives of old ice needed for paleoclimatic reconstructions and can aid efforts to extend the ice core record further back in time.