Triple Pundit: Later this year ministers, scientists, diplomats and heads of state from more than 190 countries will convene in Paris for COP 21 with the ambitious goal of adopting a binding international treaty to limit greenhouse gas emissions from human activity. The enormity of that task can be distilled to one number: two. Climate scientists warn that a 2 degrees Celsius rise of average global temperatures from pre-industrial levels is a conservative maximum to avoid the most devastating impact of rapid climate...