"But the unpleasant reality is that if climate change is going to be as bad as the believers say - and it must be said that mounting evidence is not on the sceptics' side - then buying a few eco-friendly lightbulbs for the villagers of Assam will be little more than the environmental equivalent of going to confession."

Carbon credits in its current form is not a solution on the scale we need. It is similar however to the pollution credit system free market economists (mostly republicans) started pushing in the late 80s. In theory it was a good idea because it set a ceiling on total pollution and allowed the free market to determine the most efficient way to acheivce pollution abatement. What appears to be lacking in the carbon credit system is a ceiling on carbon emissions.