The Cryosphere Discussions www.the-cryosphere-discuss.net 1994-0432 1994-0440 2 3 2008 10.5194/tcd-2-341-2008 http://www.the-cryosphere-discuss.net/2/341/2008/ http://www.the-cryosphere-discuss.net/2/341/2008/tcd-2-341-2008.html http://www.the-cryosphere-discuss.net/2/341/2008/tcd-2-341-2008.pdf 341 382 2008-05-23 Changes of Wilkins Ice Shelf over the past 15 years and inferences on its stability M. Braun matthias.braun@uni-bonn.de A. Humbert A. Moll Center for Remote Sensing of Land Surfaces (ZFL), University of Bonn, Germany Institute for Geophysics, University of Muenster, Germany The Wilkins Ice Shelf is situated along the Antarctic Peninsula, a region where seven ice shelves disintegrated between 1995 and 2002. This study combines various remote sensing data sets over Wilkins Ice Shelf, with the aim to detect its present and near-past dynamics as well as recent changes. The survey includes structural mapping, ERS-1/2 SAR interferometry and analysis of ICESat GLAS ice surface elevation data. Ice front retreat rates from 1986 to 2008 showed distinct break-up events, including a recent event in February 2008, where 40% of a bonding of the ice shelf to two islands broke off. Surface elevations have been used to study tidal effects, crack formation and to estimate the ice thickness over the floating area. The interferometric velocities cover the south-eastern part of the ice shelf as well as major tributaries and reveal maximum inflow speeds of up to 330 ma^−1. We show that drainage of melt ponds into crevasses were of no relevance for the break-up at Wilkins Ice Shelf. Buoyancy forces caused the rift formation before the break-up of February 2008. Additionally, the evolution of failure zones of the order of tenths of kilometres in length in pre-conditioned locations at ice rises could be shown. 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