Circumpolar deep water upwelling is a primary source of 10Be in Antarctic continental shelf sediments

• Published in: Global and Planetary Change
• Main Authors: Jeromson, Matthew, Fujioka, Toshiyuki, Fink, David, Simon, Krista, Smith, James, Hillenbrand, Claus-Dieter, Kuhn, Gerhard, Post, Alexandra, Sanchez-Palacios, Tona, Blaxell, Marcello, Enge, T. Gabriel, White, Duanne
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier B.V. 2024
• Subjects: Antarc*; Antarctic; Ice Sheet; Ice Shelf
• Online Access: https://doi.org/10.1016/j.gloplacha.2024.104424; https://researchportal.murdoch.edu.au/esploro/outputs/journalArticle/Circumpolar-deep-water-upwelling-is-a/991005650570007891; https://researchportal.murdoch.edu.au/view/delivery/61MUN_INST/12160406930007891/13160577410007891

Beryllium-10 (10Be) has been proposed as a potential proxy for investigating ice shelf presence and absence, or meltwater discharge in coastal polar environments. However, the sources and distribution of atmospherically produced meteoric-10Be in the Antarctic marine realm are yet to be fully characterized, making any inferences about its concentration in sediments challenging. We present a dataset of 9Be and 10Be concentrations, and 10Be/9Be ratios in seafloor surface sediments from the Antarctic continental shelf - including from sub ice shelf cores - to assess the sources and processes contributing Be-isotopes to ice-sheet proximal marine settings. We show that upwelling waters (e.g. Circumpolar Deep Water) are a significant source of 10Be to continental shelf sediments. This limits the use of 10Be/9Be as a proxy for ice shelf environment or meltwater discharge, but instead provides a potential proxy for reconstructing Circumpolar Deep Water incursions onto Antarctic continental shelves.