The ISMIP-HOM benchmark experiments performed using the Finite-Element code Elmer

Abstract

Abstract. The aim of this paper is to describe in detail how the benchmark tests ISMIP-HOM (Ice Sheet Model Intercomparison Project – Higher-Order ice-sheet Model) has been performed using the open-Source finite element code Elmer (http://www.csc.fi/elmer). The ISMIP-HOM setup consists of five diagnostic and one prognostic experiments, for both 2-D and 3-D geometries. For all the tests, the full-Stokes equations are solved. Some FE technical points, such as mesh characteristics, stabilisation methods, numerical methods used to solve the linear system and parallel performance are discussed. For all these setups, the CPU time consumption is analysed in comparison to the accuracy of the solution. Some general rules are then inferred that optimise the computing time versus the accuracy of the results.