The outlet glacier of Basin 3 (B3) of Austfonna ice cap, Svalbard, is one of the fastest outlet glaciers in Svalbard, and shows dramatic changes since 1995. In addition to previously observed seasonal summer speed-up associated with the melt season, the winter speed of B3 has accelerated approximately fivefold since 1995. We use the Elmer/Ice full-Stokes model for ice dynamics to infer spatial distributions of basal drag for the winter seasons of 1995, 2008 and 2011. This "inverse" method is based on minimising discrepancy between modelled and observed surface velocities, using satellite remotely sensed velocity fields. We generate steady-state temperature distributions for 1995 and 2011. Frictional heating caused by basal sliding contributes significantly to basal temperatures of the B3 outlet glacier, with heat advection (a longer-timescale process than frictional heating) also being important in the steady state.
Arctic Centre, University of Lapland, Rovaniemi, Finland; VAW, Eidgenossische Technische Hochschule Zürich, ETHZ, Switzerland; Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, TAS, Australia; CSC - IT Center for Science Ltd., Espoo, Finland; Gamma Remote Sensing and Consulting AG, Gümligen, Switzerland; Danish Meteorological Institute, Copenhagen, Denmark; Department of Earth Sciences, Uppsala University, Uppsala, Sweden; College of Global Change and Earth System Science, State Key Laboratory of Remote Sensing Science, Beijing Normal University, Beijing, China
Recommended Citation:
Gladstone R,, Schäfer M,, Zwinger T,et al. Importance of basal processes in simulations of a surging Svalbard outlet glacier[J]. Cryosphere,2014-01-01,8(4)