Java Climate Model - Archive of older versions

"JCM5" 2005-2009

Since 2005 JCM became an application launched using Java5 and WebStart, and has been hosted here at

June 2011 Current version of JCM (also shared on SVN)
Feburary 2009 Prior to adding Copenhagen pledges
October 2008 Including new regional emissions data / effort-sharing projections for Swiss project on emissions pathways
March 2007 Core science updates (using IPCC AR4), partial documentation update, usability improvements
October 2006 Version for ABCI project including Aviation Emissions & Forcing
March 2006 Frames version, includes new LUC module, new methods for attribution of responsibility, and wiki-doc system
June 2005 Early experimental Java 5 version with only free-floating internal windows, includes new parallel worlds structure

Note: these all work ok from downloaded jar files, but webstart may stall loading earlier versions across a slow network. Old "current.jcms" setup files may also crash the startup

JCM 2002-2004

Until 2004 JCM was an applet embedded in a webpage, running on Java 1.1, and hosted at

Note: these will all be loaded in a new window, as they rely on java-javascript communcation between frames

December 2004
Only Source Code Stored
Used for analysis "optimisation under uncertainty", including optimisation, SRES extension,
results presented in Trieste workshop, and included in ClimnegII report
March 2004 The most complete, well-explained version of JCM4, with interactive documentation, popular for teaching
July 2003 Added probabilistic scripting for analysis of stabilisation under uncertainty,
results presented in Firenze and WCCC Moscow
December 2002 Added analysis of attribution of responsibility for ACCC, also experimental costs module
7 July 2002 On leaving KUP Bern, including atmospheric chemistry and forcing of all 33 gases, auto-stabilise temperature
still online at
January 2002 On leaving GRID Arendal, with clear explanations and GUI, also SRES scenarios
(used for

Note: you may get a problem opening these sequentially without closing the web browser - due to java static classes retained in memory!

2000-2001 - Chooseclimate interactive applet => JCM

July 2001 First version of "JCM" as proof of concept,
after work in Edinburgh adding other gases, solar+volcanos, sea-level rise, etc.
presented at IGBP Open-Science conference, later UNFCCC COP7 Marrackech
March 2001 Version on leaving Denmark, with help from Jesper Gundermann to incorporate UDEB heat and Hilda carbon models
November 2000 Multilingual version developed for Experimentarium, Denmark
May 2000 Chooseclimate interactive graphics - illustrating key decisions of C&C, vote to save the climate!
Note - press the stop button and choose the step-by-step intro!

The code here was designed for java version 1.0 and web browsers of 2000, so there may be some problems now!