Holman Jenkins on “global warmism”

Holman Jenkins, in his Wall Street Journal column today, coins a new term, “global warmism,” to describe the blind fealty which climate alarmism seems to command in certain circles, within which Al Gore is revered these days.

How this [Nobel Peace Prize] honor has befallen the former Veep could perhaps be explained by another Nobel, awarded in 2002 to Daniel Kahneman for work he and the late Amos Tversky did on “availability bias,” roughly the human propensity to judge the validity of a proposition by how easily it comes to mind.

Their insight has been fruitful and multiplied: “Availability cascade” has been coined for the way a proposition can become irresistible simply by the media repeating it; “informational cascade” for the tendency to replace our beliefs with the crowd’s beliefs; and “reputational cascade” for the rational incentive to do so.

Mr. Gore clearly understands the game he’s playing, judging by his resort to such nondispositive arguments as: “The people who dispute the international consensus on global warming are in the same category now with the people who think the moon landing was staged in a movie lot in Arizona.”

Here’s exactly the problem that availability cascades pose: What if the heads being counted to certify an alleged “consensus” arrived at their positions by counting heads?

It may seem strange that scientists would participate in such a phenomenon. It shouldn’t. Scientists are human; they do not wait for proof; many devote their professional lives to seeking evidence for hypotheses (especially well-funded hypotheses) they’ve chosen to believe.

Ideas, of course, have consequences, so the consequences of ideas that reinforce themselves because they’re accepted deserve to be met with special wariness. Fortunately, Jenkins points out, such self-reinforcement cannot go on forever when the ideas are wrong.

Public opinion cascades are powerful but also fragile–liable to be overturned in an instant when new information comes along. The current age of global warming politics will certainly end with a whimper once a few consecutive years of cooling are recorded. Why should we expect such cooling? Because the forces that caused warming and cooling in the past, before the advent of industrial civilization, are still at work.

Hopefully the breaking of this cascade will come sooner rather than later. Given that the -ism suffix doesn’t look so strange at the end of the phrase “global warming” and climate alarmists’ quasi-religious fervor these days, the global-warmism bubble may not have that much time left to burst before its driving force becomes, literally, a religion.