Global warming: The folly of certainty

Global warming: The folly of certainty

Larry Jones is driving the minivan across the Utah desert on Highway 163, with Sally in the passenger seat and the two kids dozing in the back. According to the map they are approaching the town of Pawoopsie. The radio is on, tuned to a Pawoopsie station that plays country music, but the reception isn't very good. Suddenly the music cuts off and an announcer's voice comes in: "static--one sixty-three--static--Pawoopsie--static--bridge collapsed--static--highway patrol says--static", and then nothing but static.

Sally sits up. "Did he say that the highway bridge in Pawoopsie collapsed?"

Larry shrugs. "I don't know."

"It sounded like that's what he was saying."

"I don't know; too much static."

"Aren't we getting close to Pawoopsie?"

"Yeah, should be a couple more miles."

Larry, don't you think you should slow down?"


"Well, if the bridge has collapsed . . ."

"Are you sure that the bridge has collapsed?"

"No, but . . ."

"Then why should I slow down?"

Here's the thing about that story: it's not at all hard to understand. You can tell it to 100 people, and 99 of them will realize that Larry Jones is being stupid. It doesn't take a brilliant mind to figure out that when you're hurtling toward possible catastrophe, only a fool would refuse to slow down and start paying attention.

Unfortunately, when it comes to the current debate about climate change, the scientific community has somehow worked itself into the position of implicitly assuming that the public are too stupid to understand that story. We have been treating the public as though they are a large mass of Larry Joneses. That's a blunder, and one that has cost us big time.

The debate about climate change, as it is currently conducted, focuses mainly on this question: Are we certain that the Earth is going to warm to a dangerous degree in the near future? Climate scientists have been struggling very hard to convince us all that they are certain, or at least nearly certain, but haven't succeeded all that well.

But that's really not the right question at all. To think that is the right question is to behave like Larry Jones. The right question is: Are we confident that the Earth is *not* going to warm to a dangerous degree in the near future?

If we're not confident of that, we'd be idiots not to at least slow down and start making serious plans.

I don't believe that people are too stupid to understand that logic.

And the thing is, this is a much stronger basis for argument. Certainty is inherently hard to achieve when it comes to climate predictions. Climate depends on lots of variables in complicated ways, and many of them have not been measured with much precision. But if we stop talking about certainty and simply focus on the odds, then the situation clears greatly. There may be a few semi-plausible models that fail to predict serious warming, but the majority of models -- and the models that have the greatest acceptance in the community -- certainly do. Even if a skeptic prefers the models that don't predict warming, can the skeptic really be *sure* that they are the correct ones?

If one isn't sure, then to argue against any action at all is to behave like Larry Jones. A skeptic need not believe that we must immediately destroy the world's economy by shutting down our use of fossil fuels -- it would be just as stupid for Larry Jones to jam down the brakes in the middle of the freeway as to do nothing -- but even a skeptic must see that prudence calls for slowing down, getting as much information as we can, and making contingency plans.

Image: Modified from photo by Marc Averette

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