The aim of this work is to present a phenomenological constitutive flow model
for polar ice derived from so-called mesoscopic considerations and its consistent implementation into an  appropriate finite element scheme. A systematic investigation of the development of texture in isothermal
polar ice is presented.
From the viewpoint of numerics the flow of ice is considered as a stationary
free surface Stokes flow fully coupled with the development of its texture.
Boundary conditions at the free surface are accomodated in the course of the
computation to the actual flow situation. It turned out that the choice of the velocity boundary conditions at the bottom (bed-rock) is the crucial point in modelling induced anisotropy of free surface flow.