Description

SICOPOLIS (SImulation COde for POLythermal Ice Sheets) is a 3-d dynamic/thermodynamic model that simulates the evolution of large ice sheets and ice caps. It was originally created by Greve (1997a,b) in a version for the Greenland ice sheet. Since then, SICOPOLIS has been developed continuously and applied to problems of past, present and future glaciation of Greenland, Antarctica, the entire northern hemisphere, the polar ice caps of the planet Mars and others.

The model is based on the shallow ice approximation for grounded ice, the shallow shelf approximation for floating ice (e.g., Greve and Blatter 2009) and, optionally, hybrid shallow-ice–shelfy-stream dynamics for ice streams (Bernales et al. 2017). It is coded in Fortran and uses finite difference discretisation on a staggered (Arakawa C) grid, the velocity components being taken between grid points. A variety of different thermodynamics solvers are available, namely the polythermal two-layer method, two versions of the one-layer enthalpy method, the cold-ice method and the isothermal method (Greve and Blatter 2016).

The coding is based on a consequent low-tech philosophy. All structures are kept as simple as possible, and advanced coding techniques are only employed where it is deemed appropriate. The use of external libraries is kept at an absolute minimum. In fact, SICOPOLIS can be run without external libraries at all, which makes the installation very easy and fast.

Required model forcing:

• Surface mass balance (precipitation, evaporation, runoff).
• Mean annual air temperature above the ice.
• Eustatic sea level.
• Geothermal heat flux.

Main output (as functions of position and time):

• Extent and thickness of the ice sheet.
• Velocity field.
• Temperature field.
• Water-content field (temperate regions).
• Age of the ice.
• Isostatic displacement and temperature of the lithosphere.

References:

• Bernales, J., I. Rogozhina, R. Greve and M. Thomas. 2017.
  Comparison of hybrid schemes for the combination of shallow approximations in numerical simulations of the Antarctic Ice Sheet.
  Cryosphere 11 (1), 247-265.
• Greve, R. 1997a.
  A continuum-mechanical formulation for shallow polythermal ice sheets.
  Phil. Trans. R. Soc. A 355 (1726), 921-974.
• Greve, R. 1997b.
  Application of a polythermal three-dimensional ice sheet model to the Greenland ice sheet: Response to steady-state and transient climate scenarios.
  J. Climate 10 (5), 901-918.
• Greve, R. and H. Blatter. 2009.
  Dynamics of Ice Sheets and Glaciers.
  Springer, Berlin, Germany etc., 287 pp.
• Greve, R. and H. Blatter. 2016.
  Comparison of thermodynamics solvers in the polythermal ice sheet model SICOPOLIS.
  Polar Sci. 10 (1), 11-23.
• SICOPOLIS website: http://www.sicopolis.net/
• Changelog: http://tinyurl.com/commit-logs-sico-trunk/

Copyright

Copyright 2009-2017 Ralf Greve
(with contributions by Jorge Bernales, Heinz Blatter, Reinhard Calov, Thorben Dunse, Ben Galton-Fenzi, Thomas Goelles, Philipp Hancke, Nina Kirchner, Sascha Knell, Alex Robinson, Tatsuru Sato, Malte Thoma, Roland Warner)

License

SICOPOLIS is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

SICOPOLIS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with SICOPOLIS. If not, see http://www.gnu.org/licenses/.