Bristol 24-7: After the disappointment of Copenhagen, many climate activists feel wholly dispirited about the world’s ability to prevent catastrophic global warming. But all is not yet lost, as one of Britain’s key climate experts made clear in a debate in the House of Lords on Friday. Lord Stern of Brentford, author of the influential 2006 Stern Review on the cost of tackling global warming, admitted the outcome of the Copenhagen climate change talks was “disappointing” and “chaotic” , but said …