In his regular column, BBC environment analyst Roger Harrabin looks at how the world's leading authority on climate science has been rocked by allegations of serious faults in its key report.
A BLEAK FORECAST?
Environmentalists are facing a bleak year ahead in the battle over climate change.
In the latest of a series of setbacks, the Chinese government is reported to be demanding that the climate change "Bible" - the report from the Intergovernmental Panel on Climate Change (IPCC) - should in future contain comments by climate sceptics, too.
It follows two severe political setbacks in the US and three allegations of serious faults in climate science itself.
In the US, the loss of the Massachusetts Senate seat almost certainly puts the nail in the coffin of Democrat hopes for a full climate bill this year.
The coffin lid was screwed shut by a controversial ruling by the Supreme Court last week that corporations should be afforded the same rights as individuals - and therefore should be able to spend as much as they want on advertising to attack politicians' plans. The fossil fuel industry is poised with banknotes at the ready.
It's just as rocky on the road of science.
Before Christmas came the first of a series of shocks: "Climategate", in which stolen e-mails purported to show scientists from the University of East Anglia (UEA) conspiring against their rivals.
It's normal behaviour in the laboratories of the world, several scientists told me. But many didn't read it that way. And the investigation into the affair will surely have serious consequences for the university and the process of climate science.
Then, as reported by the BBC News website, in December came an inexplicable blunder by the world's leading authority, the IPCC.
Its warning that Himalayan glaciers could disappear by 2035 was a huge mistake - but the IPCC said it was human error and should not undermine confidence in the rest of its 3,000-page report.
Now there have been new allegations over the weekend that the IPCC overstated the certainties of the link between rising temperatures and the costs of natural disasters - allegations the organisation strongly rebuts.
An eminent - and distressed - Oxbridge professor of natural sciences asked me at the weekend: "What's happening - how is science losing support of the public?"
Part of the answer lies with the media - particularly right-wing newspapers - which have been fuelling cynicism over government "green" taxes for some time.
So what happens now?
Xie Zhenhua, vice-chairman of China's influential National Development and Reform Commission, is reported by India's Business Standard to have demanded that the IPCC's next report should include contrarian views.
Some critics go further, calling for the IPCC chairman, Dr RK Pachauri, to resign (an offer he has declined) or even for the body to be disbanded altogether.
But governments will be loath to kill off the IPCC, which comprises hundreds of experts reviewing the work of thousands of experts, all supervised by government representatives.
With the IPCC's shortcomings laid bare, reform looks inevitable. But the body remains the guide to the complex and contested uncertainties of climate change - a phenomenon most scientists still consider a major threat to humanity.
The Prime Minister Gordon Brown said: "I think that the academic evidence as a whole leads to one conclusion - that we've got to take action against climate change. And, I don't think there was any disagreement amongst the major countries at Copenhagen that (if we) allowed temperature rise above two degrees centigrade by 2050 - it would be very serious indeed."
But even as he spoke, Mr Brown faced criticism from a different quarter on the same subject.
The World Development Movement says it has learned that the whole of the $1.5bn emergency finance promised by the government to help poor countries adapt to climate change will be stripped from the general overseas aid budget.
The Conservatives' David Cameron will not take succour from this latest problem for Mr Brown. Mr Cameron has re-branded his party as "vote-blue-get-green", but many of his back-benchers rank climate change as a very low priority. A couple of his Cabinet members are likely to be outright climate sceptics, and more may be driven that way if right wing newspapers continue chasing stories about the IPCC's failings.
All this is deeply baffling to mainstream climate scientists. With all the uncertainties about how much the climate will change in future, it is very widely accepted that humans have changed the climate and will change it more.