Rise of the Ellsworth mountains and parts of the East Antarctic coast observed with GPS

Abstract

[1] Using GPS observations from 1996 to 2011, we constrain postglacial rebound in Antarctica. Sites in the Ellsworth mountains, West Antarctica, are rising at ≈5 ± 4 mm/yr (95% confidence limits), as in the postglacial rebound model of Peltier, but ≈10 mm/yr slower than in the model of Ivins and James. Therefore significant ice loss from the Ellsworth mountains ended by 4 ka, and current ice loss there is less than inferred from GRACE gravity observations in studies assuming the model of Ivins and James. Three sites along the coast of East Antarctica are rising at 3 to 4 ± 2 mm/yr, in viscous response to Holocene unloading of ice along the Queen Maud Land coast and elsewhere. Kerguelen island and seven sites along the coast of East Antarctic are part of a rigid Antarctica plate. O'Higgins, northern Antarctic peninsula, is moving southeast at 2.3 ± 0.6 mm/yr relative to the Antarctic plate.