I've been getting lots of e-mail about my column on the environmental crisis of the moment, global warming.

 "John, we already have Geraldo to make an ass of himself -- that job is already taken. You (and your ilk) are adding to global warming by spewing this hot air from your pucker brush." Then came: "Boy when you sell out, you really sell out don't you ... What a sh-t bag you've turned into." And another writes: "All of the cow flatulence in the world can't equal the effect of the odiferous steam rising from the pile of bull---- that you lay down." Thank you, Mr. Thompson.

 The e-mails I got were quite similar, because they're based on the same critical web page -- sometimes "based on" as in "copied": One person even forwarded me my own photograph. The web page calls my column "misleading" because "studies by the United Nations Intergovernmental Panel on Climate Change (IPCC) in 1996 and 2001, and a 2001 National Academy of Sciences report, commissioned by the Bush administration, have recognized global climate change. The Pew Center on Global Climate Change and the Union of Concerned Scientists both also note a 'strong consensus' among climate researchers that global warming is a scientific reality."

 Sounds devastating, as if I had ignored basic science, but when I discussed Michael Crichton's argument that we needn't worry about global warming, I didn't deny that warming was a "scientific reality." Crichton doesn't deny it. The earth has warmed about one degree in the past 100 years. Climate changes . It always has. I reported on the real warming trend in my TV special, "Tampering With Nature." The real question is whether the warming is a "crisis," and whether trying to "fix" it will help or just wreck the lives of the poor.

 Still, by citing scientific reports, the critical web page implies that Crichton and I have the science wrong. It's a clever way to smear.

  As for the "Pew Center on Global Climate Change and the Union of Concerned Scientists," they belong more to the Left than to science. The key word in "Union of Concerned Scientists" isn't "Scientists" -- you don't need any particular degree or experience to join -- but "Concerned," and the concerns in question are decidedly left wing. Its own website reveals that it developed out of a campaign to make students think that strengthening the American military was an illegitimate use of technology.

 Stan Duncan, who at least bothered to paraphrase the smear site, complains, "You highlighted Crichton's view that climate scientists have an incentive to exaggerate global warming in order to win grants. But you did not mention that the inverse is true: Many global warming skeptics receive generous funding to downplay the problem -- for example, from energy companies with a stake in opposing regulation of fossil fuel emissions."

 Sounds like the skeptics are all doing it for money. But while some of those scientists do get money from the energy industry -- that is, from people who make their living providing products on which nearly everything we do depends -- it's nowhere near as "generous" as the millions the scaremongers collect. And the scientists tend to get the funding after their research led them to skepticism. Many get no industry funds. Suggesting corruption is a just another smear.

 The inspiration for the hate mail is a group called "Media Matters for America." The man behind it is David Brock. Brock first made his reputation fighting viciously for the right wing: He published a book called "The Real Anita Hill." Now he fights viciously for the Left.

 Thirty years ago this month, Newsweek reported: "There are ominous signs that the Earth's weather patterns have begun to change dramatically and that these changes may portend a drastic decline in food production -- with serious political implications for just about every nation on Earth. The drop in food output could begin quite soon, perhaps only 10 years from now." The headline? "The Cooling World." That's right: Just 30 years ago, scaremongers were telling us about global cooling . The alarmists never stop. Maybe the key issue isn't science. Maybe they just want us to be "concerned."

 John Stossel is co-anchor of ABC News' "20/20" and the author of "Give Me a Break," just released in paperback.