Abstract:

Accurate projections of mass loss from the Antarctic Ice Sheet depend on precise modelling of ice flow. Ice flow is routinely modelled as a non-Newtonian fluid using a power law called Glen’s flow law, but this approach neglects the inherent direction-dependent viscosity of ice. This simplification leads to a discretised ice-sheet model that is both computationally efficient and numerically stable, capable of modelling entire ice sheets. However, model intercomparison projects have revealed large discrepancies between ice-sheet models and uncertainty in future sea level projections. In this talk, I will present an overview of model developments in the area of anisotropic ice-flow modelling, an alternative to Glen’s flow law that accounts for the evolution of the crystal orientation of ice, offering a more accurate representation of ice dynamics. I will present 3D simulations of coastal regions of Antarctica, comparing modelled crystal orientation with observations of ice crystal structure obtained from quad-polarimetric radar data.