Rapid subglacial erosion beneath Pine Island Glacier, West Antarctica

• Published in: Geophysical Research Letters
• Main Authors: Smith, A.M., Bentley, C.R., Bingham, R.G., Jordan, T.A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2012
• Subjects: Glaciology; West Antarctica; Pine Island Glacier; Antarc*; Antarctica; Ice Sheet; Pine Island
• Online Access: http://nora.nerc.ac.uk/id/eprint/18799/; https://nora.nerc.ac.uk/id/eprint/18799/1/2012GL051651.pdf; https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2012GL051651

We present measurements of ice thickness, gravimetry and surface elevation on Pine Island Glacier, West Antarctica, separated by a period of 49 years. At one station, on the main trunk of the glacier we measured a surface elevation lowering with no significant change in ice thickness. We interpret these as indicating subglacial erosion of 31.8 ± 13.4 m at this location, at a mean rate over the measurement period of 0.6 ± 0.3 m a−1, and suggest that a current erosion rate of ∼1 m a−1is possible. Our results emphasize that locally, basal processes can have a significant effect on ice sheet changes, particularly where fast-flowing ice has an easily erodible bed.