Topographic steering of enhanced ice flow at the bottleneck between East and West Antarctica

• Published in: Geophysical Research Letters
• Main Authors: Winter, Kate, Ross, Neil, Ferraccioli, Fausto, Jordan, Tom, Corr, Hugh, Forsberg, René, Matsuoka, Kenichi, Olesen, Arne, Casal, Tania
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2018
• Subjects: F800 Physical and Terrestrial Geographical and Environmental Sciences; Antarctic; East Antarctic Ice Sheet; Siple; Siple Coast; Southern Ocean; The Antarctic; Weddell; West Antarctica; Antarc*; Antarctica; Ice Sheet
• Online Access: https://nrl.northumbria.ac.uk/id/eprint/34189/; https://doi.org/10.1029/2018GL077504; https://nrl.northumbria.ac.uk/id/eprint/34189/1/Topographic%20steering.pdf; https://nrl.northumbria.ac.uk/id/eprint/34189/8/2018GL077504.pdf

Hypothesized drawdown of the East Antarctic Ice Sheet (EAIS) through the ‘bottleneck’ zone between East and West Antarctica would have significant impacts for a large proportion of the Antarctic Ice Sheet. Earth observation satellite orbits and a sparseness of radio‐echo sounding (RES) data have restricted investigations of basal boundary controls on ice flow in this region until now. New airborne RES surveys reveal complex topography of high relief beneath the southernmost Weddell/Ross ice divide, with three subglacial troughs connecting interior Antarctica to the Foundation and Patuxent Ice Streams and Siple Coast ice streams. These troughs route enhanced ice flow through the interior of Antarctica but limit potential drawdown of the EAIS through the bottleneck zone. In a thinning or retreating scenario, these topographically‐controlled corridors of enhanced flow could however drive ice divide migration, and increase mass discharge from interior West Antarctica to the Southern Ocean.