Guardian: From today, based on the best estimates available, we have eight years to head-off potentially uncontrollable climatic upheaval. What can happen in eight years? Quite a lot, actually. A world war can begin, and end. Two, in fact. Last month there was a lacklustre meeting on climate change in Poznan, Poland. It was talks about more talks set to come later this year in Copenhagen. But that’s all it was, talks. Now, on New Year’s Day, hangovers and environmental ennui could prove a …