Rapid subglacial erosion beneath Pine Island Glacier, West Antarctica
نویسندگان
چکیده
[1] 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 , and suggest that a current erosion rate of 1 m a 1 is 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. Citation: Smith, A. M., C. R. Bentley, R. G. Bingham, and T. A. Jordan (2012), Rapid subglacial erosion beneath Pine Island Glacier, West Antarctica, Geophys. Res. Lett., 39, L12501, doi:10.1029/2012GL051651.
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