Leading article: Cameron's climate conundrum

In a way, the revolt in the Conservative Party against the conventional science of global warming redounds to David Cameron's credit. That so many prominent people in his party disagree with the leader's policy underlines his courage in defying the instincts of so many of his followers.

David Davis, who writes for The Independent today, is no longer a member of the shadow cabinet, but his doubts about his party's environmental policies are shared privately by many of those who are still members. Nor can Nigel Lawson, a former chancellor of the exchequer whose advice on economic subjects Mr Cameron values, be dismissed as a fringe obsessive.

The truth is that Mr Cameron has a fight on his hands. When he was filmed with huskies on a glacier long ago, his party was quiescent, willing after three defeats to pay any price for a leader that could win. But next week's Copenhagen summit has brought the issue to the fore, and the furore over leaked emails from the University of East Anglia has brought the Tory party's internet wing out in a rash.

The Independent professes itself rather baffled by climate-change sceptics. As with most conspiracy theories, the conspiracy theorists have failed to ask the one obvious question: Why? Why would more than 90 per cent of climate scientists invent the idea of global warming? But there are a lot of sceptics about, and they are over-represented among Conservatives.

That is why it is so significant that Mr Cameron has made green policies central to his modernisation of the party. We accept his sincerity on this issue, and admire his courage and willingness to stand firm against his party. The Tory party's opposition to a new runway at Heathrow is important. Beyond that, however, there remains a marshmallow quality to Mr Cameron's preparation for a genuinely green government.

The Labour Government under Gordon Brown, from a very lacklustre start, has begun to rise to the challenge of Copenhagen. How the prime-minister-in-waiting handles the challenge to his authority and develops his policies on climate change over the next six months is vital in informing the decision that the voters of Britain will soon be called upon to make.