Articles | Volume 6, issue 4
Geosci. Model Dev., 6, 1299–1318, 2013
Geosci. Model Dev., 6, 1299–1318, 2013

Model description paper 22 Aug 2013

Model description paper | 22 Aug 2013

Capabilities and performance of Elmer/Ice, a new-generation ice sheet model

O. Gagliardini1,2, T. Zwinger3, F. Gillet-Chaulet1, G. Durand1, L. Favier1, B. de Fleurian1, R. Greve4, M. Malinen3, C. Martín5, P. Råback3, J. Ruokolainen3, M. Sacchettini1, M. Schäfer6, H. Seddik4, and J. Thies7 O. Gagliardini et al.
  • 1Laboratoire de Glaciologie et Géophysique de l'Environnement, UJF-Grenoble, CNRS – UMR5183, Saint-Martin-d'Hères, France
  • 2Institut Universitaire de France, Paris, France
  • 3CSC-IT Center for Science Ltd., Espoo, Finland
  • 4Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan
  • 5British Antarctic Survey, Cambridge, UK
  • 6Arctic Centre, University of Lapland, Rovaniemi, Finland
  • 7Uppsala University, Uppsala, Sweden

Abstract. The Fourth IPCC Assessment Report concluded that ice sheet flow models, in their current state, were unable to provide accurate forecast for the increase of polar ice sheet discharge and the associated contribution to sea level rise. Since then, the glaciological community has undertaken a huge effort to develop and improve a new generation of ice flow models, and as a result a significant number of new ice sheet models have emerged. Among them is the parallel finite-element model Elmer/Ice, based on the open-source multi-physics code Elmer. It was one of the first full-Stokes models used to make projections for the evolution of the whole Greenland ice sheet for the coming two centuries. Originally developed to solve local ice flow problems of high mechanical and physical complexity, Elmer/Ice has today reached the maturity to solve larger-scale problems, earning the status of an ice sheet model. Here, we summarise almost 10 yr of development performed by different groups. Elmer/Ice solves the full-Stokes equations, for isotropic but also anisotropic ice rheology, resolves the grounding line dynamics as a contact problem, and contains various basal friction laws. Derived fields, like the age of the ice, the strain rate or stress, can also be computed. Elmer/Ice includes two recently proposed inverse methods to infer badly known parameters. Elmer is a highly parallelised code thanks to recent developments and the implementation of a block preconditioned solver for the Stokes system. In this paper, all these components are presented in detail, as well as the numerical performance of the Stokes solver and developments planned for the future.