Isotopic signature of massive, buried ice in eastern Taylor Valley, Antarctica: Implications for its origin. Issue 1 (31st December 2022)

• Record Type: Journal Article
• Authors: Gardner, Christopher B.; Diaz, Melisa A.; Smith, Devin F.; Fountain, Andrew G.; Levy, Joseph S.; Lyons, W. Berry
• Is Part Of: Arctic, antarctic, and alpine research. Volume 54:Issue 1(2022)
• Page Start: 335
• Page End: 345
• Publication Date: 2022-12-31
• Subjects: Buried ice -- McMurdo Dry Valleys -- Last Glacial Maximum -- ice-cored moraine; Polar regions -- Periodicals; Alpine regions -- Periodicals; Alpine regions; Cold Climate; Arctic Regions; Electronic journals; Periodicals; 570.998
• DOI: 10.1080/15230430.2022.2102510
• Languages: English
• ISSNs: 1523-0430

Abstract

ABSTRACT: The coastal regions of the McMurdo Dry Valleys, Antarctica, contain deposits of the Ross Sea Drift, sedimentary material left from the Ross Sea ice sheet from the advance of the West Antarctic ice sheet during the Last Glacial Maximum. Much of this deposit is ice-cored, but data on the stable isotopic composition of water from this ice, which may contain a valuable climate archive, are sparse or incomplete. Widespread thermokarstic ground subsidence in this "coastal thaw zone" of the McMurdo Dry Valleys suggests that these potential records are rapidly being lost due to the melting of ground ice and permafrost. We collected samples of massive buried ice from the Ross Sea Drift in eastern Taylor Valley for δ 18 O-H2 O and δ 2 H-H2 O and measured a broad range of values (δ 18 O = −27.7 to −37.3 ‰; δ 2 H = −210 to −295 ‰). These buried ice deposits do not show evidence of alteration through sublimation or evaporation, plot along the local meteoric water line, and have values that indicate ice deposition under a colder climate than present conditions. We propose that this ice was sourced from the Ross Sea ice sheet during the Last Glacial Maximum and contains a valuable and accessible climate record.