Assessing the continuity of the blue ice climate record at Patriot Hills, Horseshoe Valley, West Antarctica

• Published in: Geophysical Research Letters
• Main Authors: Winter, Kate, Woodward, John, Dunning, Stuart, Turney, Chris, Fogwill, Christopher, Hein, Andrew, Golledge, Nicholas, Bingham, Robert, Marrero, Shasta, Sugden, David, Ross, Neil
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2016
• Subjects: F800 Physical and Terrestrial Geographical and Environmental Sciences; Bia; Horseshoe Valley; Patriot Hills; West Antarctica; Antarc*; Antarctica; Ice Sheet
• Online Access: https://nrl.northumbria.ac.uk/id/eprint/26004/; https://doi.org/10.1002/2015GL066476; https://nrl.northumbria.ac.uk/id/eprint/26004/3/Winter_et_al-2016-Geophysical_Research_Letters.pdf; https://nrl.northumbria.ac.uk/id/eprint/26004/1/2015GL066476R_revised_manuscript.docx

We use high resolution Ground Penetrating Radar (GPR) to assess the continuity of the Blue Ice Area (BIA) horizontal climate record at Patriot Hills, Horseshoe Valley, West Antarctica. The sequence contains three pronounced changes in deuterium isotopic values at ~18 cal ka, ~12 cal ka and ~8 cal ka. GPR surveys along the climate sequence reveal continuous, conformable dipping isochrones, separated by two unconformities in the isochrone layers, which correlate with the two older deuterium shifts. We interpret these incursions as discontinuities in the sequence, rather than direct measures of climate change. Ice-sheet models and Internal Layer Continuity Index plots suggest that the unconformities represent periods of erosion occurring as the former ice surface was scoured by katabatic winds in front of mountains at the head of Horseshoe Valley. This study demonstrates the importance of high resolution GPR surveys for investigating both paleo-flow dynamics and interpreting BIA climate records.