Protesting too much

Seems to me the global-warming folks just keep hurting their own cause, and weakening their own argument, with two silly tactical mistakes.

The first is that they exaggerate their evidence. The second is that they bully their opponents. Both tend to be signals that they aren't as sure of themselves as they'd like you to think they are.

You've watched other people do this same sort of thing. You've listened to people argue for the theory of evolution with the same kind of false gusto, acting as if they have museums full of missing links and heaping scorn on anyone who doesn't join their choir.

But we should be honest and point out that it's not just liberals who do this sort of thing. I've watched Bible-believing Christians pretend loudly that they have all sorts of detailed evidence for exactly how the end times are going to unfold-and then seen them dismiss their fellow believers as pagans when they don't buy into their theories. Sadly, their behavior weakens their case even for what is true.

In fact, we all tend to do this sort of thing. Is your argument a little weak on facts? Well, don't worry. Just exaggerate the facts you've got, and raise your voice a little.

Associated Press did this just last week, in a story by reporter Seth Borenstein. The sensationalistic headline screamed: "Climate report warns of droughts, starvation, disease." The lead paragraph thundered on: "The harmful effects of global warming on daily life are already showing up, and within a couple of decades hundreds of millions of people won't have enough water, top scientists will say next month at a meeting in Belgium."

The AP story then goes on-not at first with words like "might" or "could"-but with flat pronouncements and firm declarations, to offer a terrifying and draconian picture of the future: "Tens of millions of others will be flooded out of their homes each year as the Earth reels from rising temperatures and sea levels. . . . Tropical diseases will spread. By 2050, polar bears will mostly be found in zoos, their habitats gone. Pests like fire ants will thrive."

Later in this terrifying picture of the future, AP begins to temper its account by saying people "could" face starvation, "could" face water shortages, and that half of Europe's plant species "could" be vulnerable, endangered, or extinct by 2100. But by the time the story backs off even that little bit, the tone is already established and the context is set. This is no longer something up for debate or discussion. This is a settled matter.

Trouble is, of course, that even the people writing the study that AP is reporting on can't get together on what they're predicting-and I don't refer here just to picky details. All the current hullabaloo stems from a series of four reports coming this year from the "Intergovernmental Panel on Climate Change," a UN-sponsored group of scientists from around the world. But that very IPCC is notable for having quietly adjusted one of its main predictions earlier this year: In 2001, the IPCC was saying that within the next few decades, we should expect to watch the oceans of the world rise by as much as 35 inches. In this year's IPCC reports, that forecast has been reduced to just 16.5 inches. And both those prognostications are supposed to be taken seriously in the context of Al Gore's warning in his famous movie that the oceans are likely to rise by no less than 10 feet!

Is global warming real? Almost certainly. Is there room for honest skepticism about its extent, its causes, and the best ways to counter it? Both the volume and the tone of the experts suggest they want to allow no such room.

And that's just the point. When voices get raised, when the facts get exaggerated, and when you're told repeatedly that the discussion is already over-that's a very good time to say in a measured tone: "Wait a minute. I still have a few more questions I'd like to ask."