RIMBAY – a multi-approximation 3D ice-dynamics model for comprehensive applications: model description and examples
- 1Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Bussestrasse 24, 27570 Bremerhaven, Germany
- 2Bavarian Academy of Sciences, Commission for Glaciology, Alfons-Goppel-Str. 11, 80539 Munich, Germany
- 3Laboratoire de Glaciologie, Département des Sciences de la Terre et de l'Environnement (DSTE), Université Libre de Bruxelles (ULB), CP 160/03, Avenue F.D. Roosevelt, 1050 Bruxelles, Belgium
Abstract. Glaciers and ice caps exhibit currently the largest cryospheric contributions to sea level rise. Modelling the dynamics and mass balance of the major ice sheets is therefore an important issue to investigate the current state and the future response of the cryosphere in response to changing environmental conditions, namely global warming. This requires a powerful, easy-to-use, versatile multi-approximation ice dynamics model. Based on the well-known and established ice sheet model of Pattyn (2003) we develop the modular multi-approximation thermomechanic ice model RIMBAY, in which we improve the original version in several aspects like a shallow ice–shallow shelf coupler and a full 3D-grounding-line migration scheme based on Schoof's (2007) heuristic analytical approach. We summarise the full Stokes equations and several approximations implemented within this model and we describe the different numerical discretisations. The results are cross-validated against previous publications dealing with ice modelling, and some additional artificial set-ups demonstrate the robustness of the different solvers and their internal coupling. RIMBAY is designed for an easy adaption to new scientific issues. Hence, we demonstrate in very different set-ups the applicability and functionality of RIMBAY in Earth system science in general and ice modelling in particular.