Guardian: Two papers on carbon emissions published in the scientific journal Nature last week were ground-breaking: they show us how much carbon dioxide we can produce if we’re to have a reasonable chance of preventing two degrees of global warming. It’s a completely different approach from the UN’s and national governments’. They set targets for reductions by a certain date but have nothing to say about the total amount of carbon we can release. One of the papers, by Myles Allen and others, …