The Earth beneath is constantly changing shape due to phenomena such as earthquakes, glacial melting and even the tides. Small deformations in the Earth’s surface (of the millimetre or even sub-millimetre scale) can now be measured due to the advent of precise GPS positioning technologies. In recent years, the theories underpinning these deformations have lagged behind the observations, necessitating the development of advanced numerical models capable of simulating Earth-scale deformation.  Seismic data indicates there are large variations in the viscosity of the mantle beneath Antarctica. This variability can affect the accuracy of models such as the Glacial Isostatic Adjustment (GIA), which are used to correct satellite measurements of ice mass change.

Focusing on ongoing deformation of Antarctica, this project will further develop advanced three-dimensional large strain finite element models of the Earth, incorporating heterogeneous structural properties and viscoelastic behaviour to examine deformation associated with one or more of these major forcings: 

• Earthquake processes and their effect on Antarctica’s ice shelves;
• Glacial melting;
• Tidal waves – either direct gravitational forcing or due to the changing mass of the
• Heating and cooling of the Earth over days and seasons and years.

Models will be compared with precise GPS or GNSS coordinate time series.