100%

That's it. That's how much we need to reduce our CO2 emissions to avoid runaway global heating. But think about it - is the de-carbonisation of our economy such a bad idea?

You could question George Monbiot's figures, but in practice when Monbiot does the maths he's usually right, and eventually others follow. He came up with the 80% CO2 cut figure a year ago in his excellent book Heat, and this figure is now accepted as the current minimum cut the UK needs to aim for, and was even mentioned recently by Gordon Brown.

What's Gordon waiting for? Permission from the CBI?