Title Dynamics of the ice cap on King George Island, Antarctica; field measurements and numerical simulations
Author Rückamp, M.; Blindow, N.; Suckro, S.K.; Braun, M.; Humbert, A.
Author Affil Rückamp, M., University of Münster, Institute of Geophysics, Munster, Federal Republic of Germany. Other: University of Bonn, Federal Republic of Germany; University of Hamburg, Federal Republic of Germany
Source Glaciology in the International Polar Year, prefaced by G.H. Gudmundsson. Annals of Glaciology, 51(55), p.80-90, . Publisher: International Glaciological Society, Cambridge, United Kingdom. ISSN: 0260- 3055
Publication Date 2010
Notes In English. Includes appendix. 27 refs. CRREL Acc. No: 64004760
Index Terms climatic change; firn; geophysical surveys; glacial geology; glaciers; ice; glacier flow; meteorology; radar; surveys; temperature; weather observations; Antarctica- -Antarctic Peninsula; Antarctica--King George Island; air; Antarctic Peninsula; Antarctica; climate change; field studies; geophysical methods; ground-penetrating radar; ice caps; ice movement; International Polar Year 2007- 08; IPY 2007-08 Research Publications; King George Island; numerical models; radar methods; Scotia Sea Islands; South Shetland Islands; three-dimensional models
Abstract King George Island is located at the northern tip of the Antarctic Peninsula, which is influenced by maritime climate conditions. The observed mean annual air temperature at sea level is -2.4°C. Thus, the ice cap is regarded as sensitive to changing climatic conditions. Ground-penetrating radar surveys indicate a partly temperate ice cap with an extended water layer at the firn/ice transition of the up to 700 m high ice cap. Measured firn temperatures are close to 0°C at the higher elevations, and they differ considerably from the measured mean annual air temperature. The aim of this paper is to present ice-flow dynamics by means of observations and simulations of the flow velocities. During several field campaigns from 1997/98 to 2008/09, ice surface velocities were derived with repeated differential GPS measurements. Ice velocities vary from 0.7 m a-1 at the dome to 112.1 m a- 1 along steep slopes. For the western part of the ice cap a three-dimensional diagnostic full-Stokes model was applied to calculate ice flow. Parameters of the numerical model were identified with respect to measured ice surface velocities. The simulations indicate cold ice at higher elevations, while temperate ice at lower elevations is consistent with the observations.
URL http://www.igsoc.org/annals/v51/55/t55A080.pdf
Publication Type journal article
Record ID 300286