CESM Models

CCSM4.0 The Complete Coupled System



The Community Climate System Model (CCSM) is a coupled climate model for simulating Earth's climate system. Composed of five separate models simultaneously simulating the Earth's atmosphere, ocean, land, land-ice, and sea-ice, plus one central coupler component, CCSM allows researchers to conduct fundamental research into the Earth's past, present, and future climate states.


  • CCSM4.0 User's Guide [html] [pdf]


Model Source Code

Copyright and Terms of Use

All CCSM source code is subject to the following Copyright Notice and Disclaimer.

Acquiring the Code

CCSM source code is distributed through a public Subversion code repository. This code can be checked out using Subversion client software, such as the command tool svn, or simply viewed with a web browser.

A short registration is required to access the repository. After registering, you will receive an email containing a user name and password that is necessary to gain access to the repository.

Acquistion of the code is more fully described in the CCSM4.0 User's Guide.

Version Summaries and Known Problems

The following table lists the available versions of code along with their test record and any known problems in the code.

Reporting a Problem

If you have any problems, please first read the User's Guide including the sections on FAQs and Use Cases. Please also refer to the CCSM Bulletin Board, which is in place to facilitate communication within the CCSM community. Finally, please also refer to the Known Problems entries that are provided with every release and release update. If questions or problems still exist, then please send an email to ccsm4-help@cgd.ucar.edu. Support questions will be answered as resources are available.