"Mankind has had less effect on global warming than previously supposed, a United Nations report on climate change will claim next year.

The UN Intergovernmental Panel on Climate Change says there can be little doubt that humans are responsible for warming the planet, but the organisation has reduced its overall estimate of this effect by 25 per cent.

In a final draft of its fourth assessment report, to be published in February, the panel reports that the level of carbon dioxide in the atmosphere has accelerated in the past five years. It also predicts that temperatures will rise by up to 4.5 C during the next 100 years, bringing more frequent heat waves and storms.

The panel, however, has lowered predictions of how much sea levels will rise in comparison with its last report in 2001.

Climate change sceptics are expected to seize on the revised figures as evidence that action to combat global warming is less urgent."

How about the fanatics will have less "evidence" that Global Warming is the End Times.

But as a sceptic I would say that even the UN admits it's previous report was wrong. In this report they are trying to make case which is more acceptable. The problem is that 4.5 C isn't enough to cause Greenland [nevermind Antarctic] from losing it's ice. Of course it's not even vaguely possible the we will get a 4.5 C increase in global temperature within the next 100 years. Continuing:

"The IPCC report, seen by The Sunday Telegraph, has been handed to the Government for review before publication.

It warns that carbon dioxide emissions have risen during the past five years by three per cent, well above the 0.4 per cent a year average of the previous two decades. The authors also state that the climate is almost certain to warm by at least 1.5 C during the next 100 years."

I don't think 1.5 C increase is likely in the next 100 years, but it's closer than 4.5 C, perhaps later UN reports will conclude that the upper limit might be 1.5 C in next 100 years- or they simply give up on the idea of predicting global temperature 100 years from now- that would be more scientifically reasonable and probably more politically reasonable. The politically best course at moment seems to lie in making prediction for longer periods like say next 200 or 1000 years. And more scientific course of action would to try to make prediction in shorter periods- like say next year or regional predictions for say the next decade- this has the value of being able to be proven right or wrong and people might actually find some use to it [rather than simply foaming at the mouth like Al Gore likes to do].
http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/12/10/nclimate10.xml