Just over six months since Britain's political party leaders were jostling to convince voters how serious they were about climate change, the issue seems to have all but disappeared off the radar screen. Prime Minister Tony Blair has called climate change "the world's greatest environmental challenge," while Conservative opposition leader Michael Howard used similar terms: "Climate change is one of mankind's greatest challenges." Surprisingly for such a major issue, it received short shrift in election manifestos, appearing well down the Labour manifesto, below most domestic issues, and got just one paragraph in the Conservative party screed. Labour acknowledged the importance of climate change and said it remains committed to its goal of a 20% cut in carbon dioxide emissions. "A 60% reduction by 2050 remains necessary and achievable," it added. But renewables got the briefest of mentions: "We will continue to develop renewable energy sources." For the Conservatives, renewables appeared in the context of guaranteeing security of energy supplies: the Tories say they will support development of a broad range of technologies. On election platforms neither of the major parties gave climate change a mention. Jonathan Poritt from the Sustainable Development Commission, the body which advises government, calls their silence on the issue "grotesque" and a dereliction of duty. "How can it be that the single most important challenge we face is not important enough to feature in election campaigns?" he asks.