Welcome to Java Climate Model

Latest version 24th March 2004
(link to older versions)
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    Meanwhile, below is a short introduction to JCM.


    Intro / Concept

    We have some choice about future climate change, it is not fate.

    However these choices are not easy. The climate-human system has many complex interacting components, so we need models to help us explore and balance the risks. Yet the ultimate 'integrated assessment model' is the global network of people's heads, so climate models must connect better with people.

    JCM is based on scientific formulae from IPCC-TAR, and can replicate key TAR predictions. It is also evolving further to investigate new research questions.

    Yet JCM is also very easy to use. Drag the arrows (policy options or scientific uncertainties), and see the effect instantly.

    In JCM everything is connected, from emissions to impacts (or sometimes, the other way). Try the "flowchart" and click on plots or modules to find the interactions.

    There are ~20 panels and many ways to arrange them. Please experiment with plot and layout menus at the top. To see more or less curves, controls and options, use the complexity menu.

    JCM is intended as a tool for global dialogue, so the model already has translations in ten languages (menu at the top)! Gradually, this is being extended to the documentation.

    JCM has extensive documentation to help you explore the topic. Clicking on a plot, menu, or arrow control, will summon specific pages (the "help" button at the top of the model switches this effect on/off). This documentation adjusts according to the current setup of the model. You can also use the search tool, or the menus introducing the topic from a variety of conceptual approaches.

    If you want to use JCM offline, you can download a package (see the link from "technical" menu -after the doc has loaded).

    JCM is not a simple one-message tool. Indeed, it has been used in climate negotiation games to demonstrate widely varying points of view, and to help explain apparent contradictions in climate science. But the fundamental message remains - together, and within limits, we can choose our future climate.

    If you like JCM and have suggestions for improvements, please write to ben2@chooseclimate.org

    Note, this documentation frame is resizable (just drag the dividing bar).


    Old versions of JCM
  • 24th december 2002
  • 8th july 2003