COP 21 at Paris: The issues, the actors, and the road ahead on climate change Amar Bhattacharya, Charles K. Ebinger, Charles Frank, Homi Kharas, Weifeng Liu, John W. McArthur, Warwick J. McKibbin, Joshua P. Meltzer, Adele Morris, Zia Qureshi, Katherine Sierra, Nicholas Stern, Amadou Sy, and Peter J. Wilcoxen Friday, November 20, 2015