CICE

CICE has several interacting components: a thermodynamic model that computes local growth rates of snow and ice due to vertical conductive, radiative and turbulent fluxes, along with snowfall; a model of ice dynamics, which predicts the velocity field of the ice pack based on a model of the material strength of the ice; a transport model that describes advection of the areal concentration, ice volumes and other state variables; and a ridging parameterization that transfers ice among thickness categories based on energetic balances and rates of strain. Additional routines prepare and execute data exchanges with an external flux coupler, which then passes the data to other climate model components such as POP. For more details, including a full set of references, see the model documentation.

Download

Source Code LACC-06-012

The CICE code is freely available under a CopyRight agreement. The code is available as a tarfile, below, or from our subversion (svn) repository via the "Browse Source" button above. The tarfile may not be completely up to date; the repository source may not be fully tested.

CICE version 4.0 (22 MB, updated 8 Dec 2008)

Regarding "Browse Source": The trunk and branches are considered development code and are password-protected. The tag directory contains the most up-to-date version of the released code and is freely accessible,  http://oceans11.lanl.gov/svn/CICE/tags/release-4.0. If you wish to collaborate with us on CICE development issues and require access to the password-protected areas, please contact Elizabeth Hunke.

Documentation

Lists of publications either about CICE (supporting documentation) or using the code are available here.

 CICE Documentation and User's Guide (pdf)

Data

Atmospheric forcing data for 1997 are also available. These data files are designed only for testing the code and are not necessarily the best observational data. Please do not publish results based on these data sets.

 1997 atmospheric data (446 MB compressed; 681 MB uncompressed)

Bug and Feature Tracking

If you need to report bugs or request features, first check the outstanding tickets. If it doesn't exist there already, submit a new ticket from the New Ticket tab above.

If you would like announcements about releases and other CICE information, you can subscribe to the cice-users list. To subscribe, send an e-mail to listmanager@… with the message "subscribe cice-users". We will have to confirm your request before you are officially added.

Release Notes

August, 2008

This model release is CICE version 4.0. It replaces CICE 3.14, which was released in August 2006. Although the model physics is similar to that of version 3.14, the code has changed substantially. Most notably, the infrastructure has been overhauled for subblocking, where the grid is first divided into blocks of grid cells that are distributed across processors for optimal load balancing. Padding cells outside the physical domain allow uneven domain decomposition. For single processor runs, subblocking may still improve performance because all-land blocks are eliminated.

Other improvements include

• an optional multiple-scattering radiative scheme
• a basic melt pond parameterization
• a passive ice age tracer; new tracers can be added easily
• multiple snow layers
• a zero-layer thermodynamics option
• alternative coupling strategies (not computing the surface temperature and wind stress, for example)
• the World Meteorological Organization definition of ice thickness categories
• support for global tripole grids
• support for regional grids with open boundaries
• block distribution via space-filling curves
• support for netCDF grid files or all-binary I/O
• dynamically allocated file units
• more history fields and namelist options
• the divergence computed from the momentum equation and the divergence implied by the remapping can be made identical, and
• coupling is now assumed to occur at the beginning/end of the timestep, rather than in the middle of the thermodynamics, simplifying the code considerably.

Updates Since Original Release

December 2008

Frequently Asked Questions

FAQ