Durban summit must accept degrees of responsibility

Two degrees Celsius. That increase in global temperatures has become synonymous with "dangerous climate change". Lobbyists haggle over it, scientists build models around it and Greens wring their hands over it. So it is dispiriting to learn, with the next round of United Nations negotiations under way in Durban, South Africa, that many climatologists feel it is a target we are almost certain to miss. (Editorial)