The UN climate change conference in Montreal has ended with environmental activists claiming a limited breakthrough in tackling global warming. It was a marathon conference that stretched beyond its scheduled two week duration and 11th hour problems threatened to derail the entire process. It needed an all-night session to forge the two key components of the deal. Kyoto’s greenhouse gas limits will continue beyond 2012 even if no new deal has been reached by then, and America will join new global talks on climate change.Conference head Stéphane Dion said: “This represents a major victory for the global community. Now national governments will have the forum to exchange experiences and analyse strategic approaches, and to free our imaginations to find innovative solutions that I know we are capable of,” he said. The UN is saying that with 40 decisions agreed on for adoption the conference is one of the most fruitful it has ever organised. However major polluters like China, India, and America have made no commitment to Kyoto’s limits, and world output of greenhouse gases continues to rise. Even signatory countries are struggling to stay on target to make their cuts in output, so the immediate effects of the conference may be slight. Montreal’s importance may lie in the beginnings of a global consensus on the problem: that it really exists, and can and must be tackled.