ABC News had a special report Wednesday night (August 31, 2006) on the end of the world. I caught little more than the last segment, which focused on what was presented as the greatest threat to human existence: global warming.

Among the claims that were repeated multiple times (by Al Gore and others) were that there was no scientific debate over whether the cause of global warming was humans. Not only did ABC liken those scientists who did not accept this orthodoxy to Holocaust deniers and to scientists who claimed that cigarettes were not associated with cancer, but ABC actually showed witness after witness for tobacco companies claiming that tobacco did not cause cancer, as if it were not enough merely to mention the analogy in passing. (Query whether that airtime could have been devoted to at least one reputable expert who disagreed with ABC's smugly certain experts?)

ABC showed experts claiming that the reason that scientific dissenters were unwilling to accept the orthodox opinion is that they were being paid by major polluters to take those positions.

ABC also reported increased hurricane activity as if it were an established scientific fact that there were now more hurricanes and that they were caused by global warming.

ABC trotted out various group studies about the impending environmental disaster, as if ABC was unaware of just how inaccurate group environmental predictions had been in the 1970s and 1980s.

Last, ABC's experts seemed quite confident that global warming could be solved by human changes, as if the main question were a lack of will. The ABC report never considered whether the drastic GNP losses associated with steps that would be predicted to make a significant difference would cause more death, poverty, and destruction than the likeliest global warming scenarios.

I was struck by how different ABC's report was than Alex Beam's latest Boston Globe column on "MIT's Inconvenient Scientist," Richard Lindzen:

In the debate over climate change, [Stanford climatologist Stephen] Schneider said [to reporters 10 years ago], there simply was no legitimate opposing view to the scientific consensus that man-made carbon emissions drive global warming. To suggest or report otherwise, he said, was irresponsible.

Indeed. I attended a week's worth of lectures on global warming at the Chautauqua Institution last month. Al Gore delivered the kickoff lecture, and, 10 years later, he reiterated Schneider's directive. There is no science on the other side, Gore inveighed, more than once. Again, the same message: If you hear tales of doubt, ignore them. They are simply untrue.

I ask you: Are these convincing arguments? . . . What am I not supposed to know?

Here's the kind of information the "scientific consensus" types don't want you to read. MIT's Alfred P. Sloan professor of meteorology Richard Lindzen recently complained about the "shrill alarmism" of Gore's movie "An Inconvenient Truth." Lindzen acknowledges that global warming is real, and he acknowledges that increased carbon emissions might be causing the warming--but they also might not.

"We do not understand the natural internal variability of climate change" is one of Lindzen's many heresies, along with such zingers as "the Arctic was as warm or warmer in 1940," "the evidence so far suggests that the Greenland ice sheet is actually growing on average," and "Alpine glaciers have been retreating since the early 19th century, and were advancing for several centuries before that. Since about 1970, many of the glaciers have stopped retreating and some are now advancing again. And, frankly, we don't know why." . . .

I decided to check out Lindzen for myself. He wasn't hard to find on the 16th floor of MIT's I.M. Pei-designed Building 54, and he answered as many questions as I had time to ask. He's no big fan of Gore's, having suffered through what he calls a "Star Chamber" Congressional inquisition by the then senator. He said he accepted $10,000 in expenses and expert witness fees from fossil-fuel types in the 1990s, and has taken none of their money since.

He's smart. He's an effective debater. No wonder the Steve Schneiders and Al Gores of the world don't want you to hear from him. It's easier to call someone a shill and accuse him of corruption than to debate him on the merits. . . .

For no apparent reason, the state of California, Environmental Defense, and the Natural Resources Defense Council have dragged Lindzen and about 15 other global-warming skeptics into a lawsuit over auto-emissions standards. California et al. have asked the auto companies to cough up any and all communications they have had with Lindzen and his colleagues, whose research has been cited in court documents.

"We know that General Motors has been paying for this fake science exactly as the tobacco companies did," says ED attorney Jim Marston. If Marston has a scintilla of evidence that Lindzen has been trafficking in fake science, he should present it to the MIT provost's office. Otherwise, he should shut up.

"This is the criminalization of opposition to global warming," says Lindzen, who adds he has never communicated with the auto companies involved in the lawsuit. Of course Lindzen isn't a fake scientist, he's an inconvenient scientist. No wonder you're not supposed to listen to him.

Several aspects of this comparison of stories were striking to me.

First, I found Lindzen's claim that "the evidence so far suggests that the Greenland ice sheet is actually growing on average" to be shocking--and (in my ignorance) implausible after everything I've read or heard in the press (including in ABC's report). Obviously, I'm not an expert, but I'd like to see Lindzen's support for this claim.

Second, Lindzen must be speaking metaphorically, rather than literally, when he claims that scientific dissent is being criminalized.

Third, I thought it questionable for ABC to present as evidence of man-made global warming an increase in category 4 hurricanes. Our weather satellites are much better than they were 30 years ago (thus missing fewer large storms), our wind recording instruments are much more widely dispersed, and the annual natural variation in big storms must be large. It is good that scientists are beginning to explore in the scholarly literature whether there might be more storms today, but for ABC to present both the supposed phenomenon and its possible cause as if they were established seemed to me to go too far--especially since it was presented along with saying that anyone who disagreed with the science they presented was like a holocaust denier or a denier of a link between cigarettes and cancer.

Fourth, from the public debate it appears that the number of reputable scientific experts who think that global warming may not be primarily man-made is small but not trivial. No historical expert believes that the holocaust did not occur. Some climate experts do not think that the evidence that global warming is primarily man-made is yet persuasive (and a few even doubt that any uncommon warming is occurring). Thus ABC's analogy to holocaust denial is inapt.

Arguments that the scientists who disagree with ABC's experts are being paid by polluters to say what they are saying is irresponsible and false if Lindzen is telling the truth. Paying someone 11 years ago to be an expert witness does not mean that he is being paid now to express opinions discussing data, some of which were compiled long after he was paid for his expertise. Generally, scientific experts are hired because of their pre-existing opinions, not the other way around.

Further, as Michael Crichton argues in Aliens Cause Global Warming, science does not work by consensus. It is based on evidence. Those scientists who try to intimidate other scientists, such as some of ABC's experts, show such little respect for the norms of science that it is hard to take their scientific opinions as seriously as they probably merit. Heavy-handed attempts to bludgeon dissident scientists into submission does not advance the cause of science, even if (as seems more likely than not to me) those doing the bludgeoning are probably correct about the main cause of global warming. And, of course, even if much of the orthodox view of global warming eventually turns out to be correct, the cure for global warming may be worse than the disease.