Articles | Volume 9, issue 5
Geosci. Model Dev., 9, 1673–1682, 2016
Geosci. Model Dev., 9, 1673–1682, 2016

Model description paper 03 May 2016

Model description paper | 03 May 2016

ICESHEET 1.0: a program to produce paleo-ice sheet reconstructions with minimal assumptions

Evan J. Gowan1,2,3, Paul Tregoning3, Anthony Purcell3, James Lea4,1,2, Oscar J. Fransner5, Riko Noormets5, and J. A. Dowdeswell6 Evan J. Gowan et al.
  • 1Department of Physical Geography, Stockholm University, Stockholm, Sweden
  • 2Bolin Center for Climate Research, Stockholm, Sweden
  • 3Research School of Earth Science, The Australian National University, Canberra, Australia
  • 4School of Environmental Sciences, University of Liverpool, Liverpool, UK
  • 5Department of Arctic Geology, The University Center in Svalbard (UNIS), Longyearbyen, Norway
  • 6Scott Polar Research Institute, Cambridge, UK

Abstract. We describe a program that produces paleo-ice sheet reconstructions using an assumption of steady-state, perfectly plastic ice flow behaviour. It incorporates three input parameters: ice margin, basal shear stress and basal topography. Though it is unlikely that paleo-ice sheets were ever in complete steady-state conditions, this method can produce an ice sheet without relying on complicated and unconstrained parameters such as climate and ice dynamics. This makes it advantageous to use in glacial-isostatic adjustment ice sheet modelling, which are often used as input parameters in global climate modelling simulations. We test this program by applying it to the modern Greenland Ice Sheet and Last Glacial Maximum Barents Sea Ice Sheet and demonstrate the optimal parameters that balance computational time and accuracy.

Short summary
We present a program that can create paleo-ice sheet reconstructions, using an assumed basal shear stress, margin location and basal topography as input. This allows for the quick determination of relatively realistic past ice sheet configurations without reliance on highly uncertain factors such as climate and ice dynamics. This is ideal for modelling Earth deformation due to the loading of ice sheets. The subsequent ice sheet configurations can be used as an input for climate modelling.