From steady state to Full Stokes - strategies in modelling paleo-ice sheets

Evan Gowan
Alfred Wegener Institute
Bremerhaven, Germany


Abstract:

Modelling ice sheets on time scales of thousands to tens of thousands of years is challenging, due to, among other things, significant uncertainties in past ice sheet behaviour, and increasing computational time when increasing the accuracy of ice physics. In this presentation, I show some of my recent work on determining the configuration and behaviour of past ice sheets. I first present a reconstruction of the western Laurentide Ice Sheet in North America using a series of time steps with steady state, plastic rheology ice. These reconstructions are based on attempting to fit observations of glacial isostatic adjustment, including modern day uplift, glacial lake shoreline tilts, and relative sea level change. Secondly, I present some preliminary results and complications of attempting to couple the shallow ice approximation and Full Stokes equations using the Ice Sheets Coupled Approximation Levels (ISCAL) for a Svalbard centred ice sheet.