A Three-Dimensional Time-Dependent Model of the West Antarctic Ice Sheet

Abstract

The area of West Antarctica which drains into the Ross Ice Shelf is examined for the purpose of understanding its dynamics and developing a numerical model to study its reaction to environmental changes. A high resolution 20 km grid is used to compile a database for surface and bedrock elevation, accumulation, and surface temperatures. Balance velocities Vb are computed and found to approximate observed velocities. These balance velocities are used with basal shear stress and ice thickness above buoyancy Z* to derive parameters k2, p and q for a sliddinq relation of the form Reasonable matching is obtained for p = 1, q = 2 and k2= 5 × 106 m3 bar−1 a−1. This sliding relation is then used in a first complete dynamic and thermodynamic velocity calculation for West Antarctica and for an improved simulation of the whole Antarctic ice sheet.