Java Climate Model

Welcome to JCM5

Updated 10th October 2006

Experimental Release
Note: this version is almost finished, it is put online for testing, please check soon for update
Please give feedback to Ben Matthews

Launch JCM5 using Java Web Start:

Java Web Start starts JCM5 as an application, with an option to use a "safe mode" where JCM5 cannot access your disk. However you must use the disk-access mode to save output, or to use the new "persistence" feature.

Webstart will cache JCM5 locally, but should automatically check for updates if you are online. (this cache may be adjusted via your "Java Control Panel" (from windows, find inside control panel).
note: if you get an error saying that the jar files are not all signed by the same key, it may be because an old copy of JCM5 remains in this cache

Note: JCM5 requires Java 5 (=1.5), it will not work with any older versions.
You can get the JRE for free from Sun at

An alternative way to start JCM5 is to save the following files to your disk:

(please come back soon for updates)

From Windows or Mac, just click on JCM5.jar to run the model.
In Linux, use the command java -jar JCM5.jar (from the directory containing these files)
Note that a jar file is a type of zip archive, but it should *not* be unzipped to run JCM.

If you want to experiment with JCM5 source code, I recommend to install Netbeans together with JDK5, (free download from, then ask me about the current project setup.

[Old info: Apparently this is no longer necessary] (Note: for Mac OS 10.4+ (only), Java 5 is available from