Exactly a fortnight from today, the United Nations climate change conference opens in Copenhagen. Its purpose is (or was) clear: to agree a successor to the Kyoto Protocol, which expires in 2012.
Under Kyoto, all those developed nations that ratified the treaty (all, in practice, except the US) agreed to cut their carbon emissions to 5 per cent below 1990 levels by 2012. The successor treaty, to be agreed at Copenhagen, was intended to secure a cut in global emissions, from the developed and developing world alike (and China has now overtaken even the US), of 50 per cent below 1990 levels by 2050, leading to more or less total decarbonisation by the end of the century.
As Gordon Brown declared in his Guildhall speech only a week ago, Copenhagen must "forge a new international agreement ... [which] must contain the full range of commitments required: on emissions reductions by both developed and developing countries, on finance and on verification".
This is a pretty tall order; and, needless to say, nothing of the sort will be agreed. Even if the Kyoto 5 per cent cut is achieved, it will be only because the developed world has effectively outsourced a large part of its emissions to countries, such as China and India, without Kyoto constraints. Not only is 50 per cent rather more severe than 5 per cent, but (except in the unlikely event of world industry migrating to Mars) a global target removes the escape route of outsourcing emissions.