Ridley himself was once a believer in warming, but disillusioned by so much of what he saw close-up in the climate-change community he has partly left the faith. Here's his explanation:
[T]he great thing about science is that it’s self-correcting. The good drives out the bad, because experiments get replicated and hypotheses put to the test. So a really bad idea cannot survive long in science.Ridley now describes himself as a "lukewarmer:"
Or so I used to think. Now, thanks largely to climate science, I have changed my mind. It turns out bad ideas can persist in science for decades, and surrounded by myrmidons of furious defenders they can turn into intolerant dogmas.
This should have been obvious to me. Lysenkoism, a pseudo-biological theory that plants (and people) could be trained to change their heritable natures, helped starve millions and yet persisted for decades in the Soviet Union, reaching its zenith under Nikita Khrushchev. The theory that dietary fat causes obesity and heart disease, based on a couple of terrible studies in the 1950s, became unchallenged orthodoxy and is only now fading slowly.
What these two ideas have in common is that they had political support, which enabled them to monopolise debate. Scientists are just as prone as anybody else to “confirmation bias”, the tendency we all have to seek evidence that supports our favoured hypothesis and dismiss evidence that contradicts it—as if we were counsel for the defence. It’s tosh that scientists always try to disprove their own theories, as they sometimes claim, and nor should they. But they do try to disprove each other’s. Science has always been decentralised, so Professor Smith challenges Professor Jones’s claims, and that’s what keeps science honest.
What went wrong with Lysenko and dietary fat was that in each case a monopoly was established. Lysenko’s opponents were imprisoned or killed. Nina Teicholz’s book The Big Fat Surprise shows in devastating detail how opponents of Ancel Keys’s dietary fat hypothesis were starved of grants and frozen out of the debate by an intolerant consensus backed by vested interests, echoed and amplified by a docile press.
This is precisely what has happened with the climate debate and it is at risk of damaging the whole reputation of science. The “bad idea” in this case is not that climate changes, nor that human beings influence climate change; but that the impending change is sufficiently dangerous to require urgent policy responses.
These scientists and their guardians of the flame repeatedly insist that there are only two ways of thinking about climate change—that it’s real, man-made and dangerous (the right way), or that it’s not happening (the wrong way). But this is a false dichotomy. There is a third possibility: that it’s real, partly man-made and not dangerous. This is the “lukewarmer” school, and I am happy to put myself in this category. Lukewarmers do not think dangerous climate change is impossible; but they think it is unlikely.There's much more at the link. His catalog of scandals among climate-change promoters, his comparison of the treatment of those who dare commit climate-change heresy with the way Islamists treat "heretics," and the egregiously sloppy science that underlies much of the popular discourse on climate-change are well-worth reading. Here's a good example to conclude with. Ridley begins it by citing some recent claims by politicians about the threat of global climate change:
I find that very few people even know of this. Most ordinary people who do not follow climate debates assume that either it’s not happening or it’s dangerous. This suits those with vested interests in renewable energy, since it implies that the only way you would be against their boondoggles is if you “didn’t believe” in climate change.
“Doubt has been eliminated,” said Gro Harlem Brundtland, former Prime Minister of Norway and UN Special Representative on Climate Change, in a speech in 2007: “It is irresponsible, reckless and deeply immoral to question the seriousness of the situation. The time for diagnosis is over. Now it is time to act.” John Kerry says we have no time for a meeting of the flat-earth society. Barack Obama says that 97 per cent of scientists agree that climate change is “real, man-made and dangerous”. That’s just a lie (or a very ignorant remark): as I point out above, there is no consensus that it’s dangerous.No wonder Ridley fears for the reputation of science.
So where’s the outrage from scientists at this presidential distortion? It’s worse than that, actually. The 97 per cent figure is derived from two pieces of pseudoscience that would have embarrassed a homeopath. The first was a poll that found that 97 per cent of just seventy-nine scientists thought climate change was man-made—not that it was dangerous. A more recent poll of 1854 members of the American Meteorological Society found the true number is 52 per cent.
The second source of the 97 per cent number was a survey of scientific papers, which has now been comprehensively demolished by Professor Richard Tol of Sussex University, who is probably the world’s leading climate economist. As the Australian blogger Joanne Nova summarised Tol’s findings, John Cook of the University of Queensland and his team used an unrepresentative sample, left out much useful data, used biased observers who disagreed with the authors of the papers they were classifying nearly two-thirds of the time, and collected and analysed the data in such a way as to allow the authors to adjust their preliminary conclusions as they went along, a scientific no-no if ever there was one.
The data could not be replicated, and Cook himself threatened legal action to hide them. Yet neither the journal nor the university where Cook works has retracted the paper, and the scientific establishment refuses to stop citing it, let alone blow the whistle on it. Its conclusion is too useful.