Hans Joachim Schellnhuber, AKA John Schellnhuber, is climate advisor to German Chancellor Angela Merkel and founder and director of the respected Potsdam Institute for Climate Impact Research (PIK). He is Professor for Theoretical Physics at the University of Potsdam and heads the European Commission s Global Change Advisory Group and the advisory board of the European Climate Foundation. Schellnhuber spoke in one of the closing panels of the July 2015 conference on Our Common Future, attended by 2000 delegates from over 100 countries. Produced by TUC Radio.