Capabilities and limitations of numerical ice sheet models

Nina Kirchner

Conceptual understanding of different types of numerical ice models, i.e. zeroth order-, higher order-, and Full Stokes ice shelf and/or ice sheet models.

References

Nina Kirchner, Kolumban Hutter, Martin Jakobsson, Richard Gyllencreutz, Capabilities and limitations of numerical ice sheet models: a discussion for Earth-scientists and modelers, Quaternary Science Reviews, Volume 30, Issues 25–26, December 2011, Pages 3691–3704, ISSN 0277-3791, DOI: 10.1016/j.quascirev.2011.09.012

Comments

Numerical ice models use different approximations depending on the region where they are applied, e.g. ice sheet, ice shelf, or ice stream (here indicated by the arrow). In sufficient upstream (downstream) distance from the grounding line, pure ice sheet flow (ice shelf flow) is described by the zero order Shallow Ice Approximation SIA (zero order Shallow Shelf Approximation SSA). When the grounding line is approached, neither a pure SIA- nor SSA-regime prevails. Hence, a simple stitching of these approximations will lead to incorrect results in the transition zone. A more correct coupling of ice sheet flow and ice shelf flow can be achieved using so-called higher (typically second) order Shallow Ice and Shallow Shelf Approximations, SOSIA and SOSSA.