CESM Models

CCSM4 Data Models


General Overview

The CCSM4 data models perform the basic function of reading external data, modifying that data, and then sending it to the driver via standard CCSM coupling interfaces. The driver and other models have no fundamental knowledge of whether another component is fully active or just a data model. In some cases, data models are prognostic and also receive and use some data sent by the driver to the data model. But in most cases, the data models are not running prognostically and have no need to receive any data from the driver.

The CCSM4 data models have been parallelized and share significant amounts of source code. Methods for reading and interpolating data have been established and can easily be reused. There is a natural hierarchy in the system. The data model calls strdata methods which then call stream methods. There are inputs associated with the data model, strdata, and streams to configure the setup. The stream methods are responsible for managing the input data. The information is then passed up to the strdata methods where the data is read and interpolated in space and time. The interpolated data is passed up to the data model where final fields are derived, packed, and returned to the driver.


  • Data Model v8 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.