Ross Garnaut's report on climate change and emissions trading scheme is due tomorrow. It is expected to find that global warming is proceeding faster than projected, and that doing nothing will be far more costly than expected. Well we know that already.

The leaks indicate that the Garnaut's final report will emphasise that there are four categories of likely damage to the economy.Today's report, a draft whose final version is due in September, will quantify only one of these, the conventional macroeconomic cost that can be estimated by economic modelling.

The second category will be the effect on particular aspects of the country. Professor Garnaut has commissioned research into the medical consequences of climate change, including deaths from heat stress.The third category will be the cost of mitigating the effects of global warming. The fourth will be a survey of how climate change affects things Australians value for more than just economic reasons - the bleaching of the Great Barrier Reef, the inundation of the Kakadu wetlands, and the loss of the West Australian karri forests.