President Barack Obama addresses the opening ceremony of the World Climate Change Conference 2015 (COP21), on November 30, 2015 at Le Bourget, on the outskirts of the French capital Paris. World leaders opened an historic summit in the French capital with 'the hope of all of humanity' laid on their shoulders as they sought a deal to tame calamitous climate change. AFP PHOTO / JIM WATSON / AFP / JIM WATSON (Photo credit should read