Welcome to CCSM

CCSM Model Support Policy

as of February 14, 2005

Code and Scripts

By CCSM we refer to the entire CCSM system and each component that it comprises. If components are also released in a stand-alone form (e.g. CAM), the stand-alone components will independently provide their own support policy.

CCSM has several release categories which are denoted by the numbering system CCSMx.y.z where "x" refers to a major release, "y" refers to substantive changes in functionality, and "z" denotes implementation changes which are not climate changing or which involve bug fixes.

CCSM code and scripts are supported for three years after the date of a major release or for six months after the next major release, whichever period is longer. Non-major releases do not have an effect on this time period. Released code, scripts and associated input datasets for major as well as non-major releases will be available on the web for that period.

Support for CSM1 has expired.
Support for CCSM2.0 and CCSM2.0.1 will continue until May 2005.
Support for CCSM3.0 will continue until at least June 2007.

CCSM will also provide periodic updates (i.e. patch distributions) of scripts and/or code that support the addition of new machines to CCSM3. These patch distributions will not have undergone the extensive testing associated with formal releases and will therefore not be supported. They will be provided for the benefit of the user community in order to more easily keep up with machine-specific improvements to CCSM3.

NOTE: CSEG is not planning any periodic updates during the spring of 2005.

CCSM will always ensure the availability of code/scripts and associated input datasets on the CCSM website.

Input Data

Input data files will accompany model source code and documentation for each release and correspond to the default data required by the run scripts provided with the release.

Machine Categories

Category 1: Fully Supported Machines (e.g. Climate Validated)
Category 2: Machines where CCSM passes restart test
Category 3: Machines where CCSM builds and might run
Category 4: Machines under consideration

NOTE: see http://www.ccsm.ucar.edu/support/mach_support.html.

The addition of new machines to, or removal of old systems from, the Category 1 class will be based upon the availability of future CCSM production capability.

Levels of Support

CCSM support will be machine-specific:

Category 1: active support will be provided for compiling and running code on Category 1 machines. Because of limited CCSM support resources, should a user encounter a problem on a platform that is functionally equivalent to a Category 1 machine, support will only be given if the user migrates his code to an actual Category 1 machine and demonstrates the problem there.

Category 2: support will be provided for compiling on Category 2 machines.

Category 3: support will be provided for compiling on Category 3 machines.

Category 4: no support will be provided.

How Support is Provided

The CCSM Software Engineering Group (CSEG) has implemented a new CCSM bulletin board addressing issues such as porting to unsupported machines, data inquiries and bug reports. CSEG monitors this forum as time and priorities permit and when appropriate notifies relevant CSEG members or CCSM liaisons of issues that need response.

All problems occurring in both "plain vanilla" CCSM and non-standard CCSM (i.e. modified code and/or datasets) should be posted on the CCSM bulletin board. CSEG will not have a staff member dedicated to monitoring the bulletin board. CSEG staff will monitor the bulletin board as time and priorities permit.

Non-standard CCSM can encompass the following scenarios;

The user is using build/run scripts other than the ones in the release;
The user has modified the released CCSM source code;
The user is using input/boundary data sets other than the ones in the release;
The user is using configurations of the system that have not been tested by CCSM (e.g. T5_gx3v5, T170_gx1v3).

Problems with non-standard CCSM will be dealt with on a case-by-case basis that will be up to the discretion of either the relevant CSEG liaison or CCSM scientific liaison.

When problems are resolved, the CCSM User's Guide, FAQ and CCSM bulletin board will be updated as time permits to reflect the resolution.

CCSM Project

The Community Climate System Model (CCSM) is a fully-coupled, global climate model that provides state-of-the-art computer simulations of the Earth's past, present, and future climate states.

CCSM is sponsored by the National Science Foundation (NSF) and the U.S. Department of Energy (DOE). Administration of the CCSM is maintained by the Climate and Global Dynamics Division (CGD) at the National Center for Atmospheric Research (NCAR).