The Java Climate Model aims to help bridge that gap, by enabling anybody on the web to experiment with climate models and policy options. Parameters are adjusted simply by dragging graphical controls with a mouse in a web browser, causing an instant response in several linked plots (including regional and per-capita emissions, carbon cycle, radiative forcing, global temperature, sea-level, regional climate maps, etc.) Thus the human-carbon-climate system is presented in a dynamic, mechanical way, so it’s easy to see “cause and effect” by “playing” with parameters. This is not another "data visualiser" but a complete model, yet fast and compact (downloadable in a few seconds, then also working offline).
To enhance credibility, the core calculation implements the same simple upwelling-diffusion carbon-cycle and climate models (fitted to AOGCM results), as used to make many of the smooth-curve plots in the recently published IPCC TAR (WG1). Although these U-D box models are conceptually simple, it has nevertheless been challenging to develop an instant response to moving controls. This was achieved using an efficient but exact eigenvector-matrix calculation method, originally developed by Jesper Gunderman for DEA-CCAT's earlier online web model. To check the accurate fit to the IPCC predictions, the SRES data tabulated in the report may be plotted alongside the model curves.
All model calculations are within one timestep loop, therefore climate-carbon and other biogeochemical feedbacks are easily incorporated. Deliberate climate-emissions policy feedbacks or "geocybernetics" may also be investigated. Despite efforts to explain models, many policymakers don't trust predictions and prefer to respond after observed changes. Some problems with a responsive approach to climate control are illustrated by formulae adjusting emissions according to recent temperature trends. The slow response from emissions to impacts leads to oscillations, exacerbated by misleading effects of temporary aerosol cooling. Nevertheless specified targets may be approached this way.
The Java model is also intended to enable feedback between people worldwide, and to broaden the discussion beyond english-speaking experts.
Therefore the code structure is internationalised, making it easy to translate all the labels and pop-up information into any language (including Chinese) This may also be useful within the UNFCCC context.
The model shown here is more an evolving “proof of concepts” than a finished product, Therefore much further development is anticipated. Please read the future development page.