Title Deformation and failure of the ice bridge on the Wilkins Ice Shelf, Antarctica
Author Humbert, A.; Gross, D.; Müller, R.; Braun, M.; van de Wal, R.S.W.; van den Broeke, M.R.; Vaughan, D.G.; van de Berg, W.J.
Author Affil Humbert, A., University of Hamburg, Institute of Geophysics, Hamburg, Federal Republic of Germany. Other: Technische Hochschule Darmstad, Federal Republic of Germany; University of Kaiserslautern, Federal Republic of Germany; Utrecht University, Netherlands; British Antarctic Survey, United Kingdom
Source Glaciology in the International Polar Year, prefaced by G.H. Gudmundsson. Annals of Glaciology, 51(55), p.49-55, . Publisher: International Glaciological Society, Cambridge, United Kingdom. ISSN: 0260- 3055
Publication Date 2010
Notes In English. 11 refs. CRREL Acc. No: 64004756
Index Terms glacial geology; ice shelves; meteorology; remote sensing; weather observations; wind (meteorology); Antarctica-- Antarctic Peninsula; Antarctic Peninsula; Antarctica; failures; Global Positioning System; ice bridges; International Polar Year 2007-08; IPY 2007-08 Research Publications; satellite methods; Wilkins Ice Shelf; winds
Abstract A narrow bridge of floating ice that connected the Wilkins Ice Shelf, Antarctica, to two confining islands eventually collapsed in early April 2009. In the month preceding the collapse, we observed deformation of the ice bridge by means of satellite imagery and from an in situ GPS station. TerraSAR-X images (acquired in stripmap mode) were used to compile a time series. The ice bridge bent most strongly in its narrowest part (westerly), while the northern end (near Charcot Island) shifted in a northeasterly direction. In the south, the ice bridge experienced compressive strain parallel to its long axis. GPS position data were acquired a little south of the narrowest part of the ice bridge from 19 January 2009. Analysis of these data showed both cyclic and monotonic components of motion. Meteorological data and re-analysis of the output of weather-prediction models indicated that easterly winds were responsible for the cyclic motion component. In particular, wind stress on the rough ice melange that occupied the area to the east exerted significant pressure on the ice bridge. The collapse of the ice bridge began with crack formation in the southern section parallel to the long axis of the ice bridge and led to shattering of the southern part. Ultimately, the narrowest part, only 900 m wide, ruptured. The formation of many small icebergs released energy of ›125×106 J.
URL http://www.igsoc.org/annals/v51/55/t55A057.pdf
Publication Type journal article
Record ID 300290