Study of the dynamic state of ice shelves on the south-western Antarctic Peninsula by an interdisciplinary approach of remote sensing, fracture mechanics and modelling of ice dynamics

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This project aims to gain understanding of ongoing and potential changes of Wilkins and GeorgeVI ice shelves on the south-western Antarctic Peninsula. Both are located in an area of the supposed climatic limit of viability of ice shelves and have already shown considerable ice front retreat. The break-up events in 2008 on Wilkins Ice Shelf exemplified their potential of disintegration. We propose a multi-institutional, interdisciplinary approach including remote sensing, modelling of the ice dynamics and fracture mechanics with the aim to improve the understanding of the impacts of temperature increase on ice shelf stability. The remote sensing component will include the mapping of surface structures and fracture development over time for Wilkins Ice Shelf, as well as the derivation of surface velocity fields by SAR interferometry and feature tracking for both ice shelves, required as input datasets for modelling of fracture and ice dynamics. For this purpose, multi-temporal optical and SAR imagery will be used. The observed quantities will be interpreted in the context of ice dynamics and fracture mechanics. The glaciological modelling component includes a thermo-dynamical consistent dynamic model for ice shelf flow in shallow shelf approximation, which will be applied to both ice shelves. The model sensitivity to inflow speeds, thermal boundary conditions and grounded areas will be tested in order to gain understanding of the response to external changes. We specially focus on the incorporation of local features, e.g. rifts on Wilkins Ice Shelf, in the model. The fracture mechanic component of the project will focus on critical situations which damage the ice shelves and which lead to break-up events.