| Summary: | Ice shelves and ice caps constitute a great proportion of the glacial ice mass that covers 10% of the global land surface and is vulnerable to climate change. Large scale ice flow models are widely used to investigate the mechanisms behind the observed physical processes and predict their future stability and variability under climate change. This thesis aims at providing general remarks on the application of ice flow models in studying glaciological problems through investigating the evolution of an Antarctic ice shelf under climate change and the mechanisms of fast ice flowing events (surges) in an Arctic ice cap. In addition discussions of the equivalence of two significantly different expressions for the rate factor in Glen’s flow are also provided. Off-line coupling between the Lambert Glacier-Amery Ice Shelf (LG-AIS) drainage system, East Antarctica, and the climate system by employing a hierarchy of models from general circulation models, through high resolution regional atmospheric and oceanic models, to a vertically integrated ice flow model has been carried out. The adaptive mesh refinement technique is specifically implemented for resolving the problem concerning grounding line migration. Sensitivity tests investigating the importance of various parameters and boundary conditions are carried out in ice flow models with different approximations for Austfonna Ice-cap, Svalbard to investigate the surge event in one of its basins, Basin 3. Inverse modelling of basal friction coefficient is specifically implemented. A continuum to discrete multi-model approach is implemented for simulations of Basin 3. LG-AIS drainage system will be rather stable in the face of future warming over 21st and 22nd centuries. Although the ice shelf thins in most of the simulations there is little grounding line retreat. The change of ice thickness and velocity in the ice shelf is mainly influenced by the basal melt distribution. And the Lambert, Fisher and Mellor glaciers are most sensitive to thinning of the ice shelf south ...
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