'We face climate disaster'

The Government's chief scientist today set out an "apocalyptic vision" of global warming bringing back the conditions which drove the dinosaurs to extinction.

Professor Sir David King told a House of Lords committee that urgent action was needed "within the next few years" to avert the threat of sudden and severe climate change.

He claimed that last summer's heatwave was a man-made event and a warning sign of worse to come.

And he defied Downing Street by repeating his charges that global warming is a bigger threat than terrorism, and that Washington is failing to tackle the problem.

On a recent trip to America to talk about the threat of global warming, Sir David was warned by Downing Street to limit his contact with the media.

A memo from a No10 aide was leaked to a journalist in Seattle, where the scientist was delivering a lecture.

Today, Sir David told the peers that the level of carbon dioxide in the atmosphere was probably the highest it had been for 65 million years, since the Palaeocene epoch when most dinosaurs became extinct.

He said the era saw a "massive reduction" in life on earth and added: "The Antarctic was the best place to be at that time. The rest of the world was virtually uninhabitable."

He also delivered a thinly-veiled attack on President George Bush by praising the effort which individual American states were making to curb their carbon dioxide emissions, in the absence of a ruling from Washington.

And he accused American oil giant Exxon of funding lobbyists who are trying to undermine the consensus on global warming by suggesting that scientists are divided on the nature of the problem.

Sir David said: "This is the biggest issue for us to face this century.

"It's man-made. The science is done. It's complete. It's a matter of political understanding. I personally have little doubt that unfortunately, as time moves on, the global warming events such as the very high temperatures in Europe over the past summer and the flooding two years before will occur more frequently, and the understanding of what's driving these will become more apparent.

"And I think nations across the world will understand... that action has to be taken."

In the past few centuries, carbon dioxide in the air has risen from 270 to 370 parts per million and is still on the increase, Sir David said.

He predicted that if the level reached 550 parts per million, the polar ice caps would melt and the Gulf Stream current would be reversed, plunging Europe into a new ice age while the rest of the globe overheated.

To avoid that threat, he said, the level needed to be stabilised at 450 parts per million.