Title Geometry and thermal regime of the King George Island ice cap, Antarctica, from GPR and GPS
Author Blindow, N.; Suckro, S.K.; Rückamp, M.; Braun, M.; Schindler, M.; Breuer, B.; Saurer, H.; Simoes, J.C.; Lange, M.A.
Author Affil Blindow, N., University of Münster, Institute for Geophysics, Munster, Federal Republic of Germany. Other: University of Bonn, Federal Republic of Germany; University of Freiburg, Federal Republic of Germany; Universidad Federal do Rio Grande do Sul, Brazil
Source Glaciology in the International Polar Year, prefaced by G.H. Gudmundsson. Annals of Glaciology, 51(55), p.103-109, . Publisher: International Glaciological Society, Cambridge, United Kingdom. ISSN: 0260- 3055
Publication Date 2010
Notes In English. 21 refs. CRREL Acc. No: 64004763
Index Terms geophysical surveys; glacial geology; glaciers; ice; ice cover; ice cover thickness; radar; remote sensing; surveys; temperature; thermal regime; Antarctica--King George Island; Antarctica; geometry; geophysical methods; Global Positioning System; ground-penetrating radar; ice caps; International Polar Year 2007-08; IPY 2007-08 Research Publications; King George Island; radar methods; satellite methods; Scotia Sea Islands; South Shetland Islands
Abstract King George Island is the largest of the South Shetland Islands, close to the tip of the Antarctic Peninsula. The annual mean temperature on the island has increased by 1°C during the past three decades, and the ice cap that covers the majority of the island is sensitive to climatic change. We present data from two field campaigns (1997 and 2007): 700 km of global positioning system (GPS) and ground-penetrating radar (GPR) profiles were collected on Arctowski Icefield and on the adjacent central part. The data were analysed to determine the surface and bed topography and the thermal regime of the ice. Average ice thickness is 250 m and maximum thickness is 420 m. The GPR profiles show isochrones throughout the ice cap which depict the uparching of Raymond bumps beneath or close to the ice divides. A water table from percolation of meltwater in the snowpack shows the firn-ice boundary at approx. 35 m depth. The firn layer may be temperate due to the release of latent heat. In the area below 400 m a.s.l., backscatter by water inclusions is abundant for ice depths below the water table. We interpret this as evidence for temperate ice. Scatter decreases significantly above 400 m. Ice temperatures below the water table in this part of the ice cap are subject to further field and modelling investigations.
URL http://www.igsoc.org/annals/v51/55/t55A070.pdf
Publication Type journal article
Record ID 300283