October 25, 2011

The announcement last week of the results of the Berkeley Earth Surface Temperature (BEST) Project by project chairman Richard Muller has caused quite a stir. True believers in catastrophic anthropogenic global warming (CAGW) have greeted it as the final nail in the coffin of dissent. Why? Because it concludes—take a deep breath, now—that “Global warming is real.”

The only thing more stunning and frightening than the idiocy of equating “global warming” with “CAGW” is the failure of so much not only of the public, and not only of the media, but especially of the scientific community—well, okay, the already committed, true-believer “scientific community”—to recognize (admit? expose?) the rhetorical sleight of hand.

I will put the point bluntly, if a little technically: BEST is a classic case of ignoratio elenchi, the logical fallacy of arguing for a point other than the one contended, and pretending that by arguing for the one one has answered the other. Other ways of putting ignoratio elenchi are “irrelevant conclusion” and “irrelevant thesis.”

Here’s the situation. Thousands of brilliant scientists—physicists and chemists (atmospheric, solar, cosmic, and more specialists), geologists, meteorologists, climatologists, statisticians, economists, and more have been debating for about a quarter of a century whether the warming all agreed had occurred since the end of the Little Ice Age (roughly the mid-nineteenth century) was largely natural or largely manmade. They’ve been debating how much of that warming should be attributed to rising concentration of carbon dioxide in the atmosphere. They’ve been debating “climate sensitivity”—how much global average temperature will rise, after feedbacks, in response to a doubling of atmospheric CO2 concentration, and whether that amount of warming will be, on balance, beneficial or harmful to humanity and the rest of life on Earth. They’ve been debating the rate at which the world’s economy would grow in the future, and how much of the energy used to spur that growth would come from CO2-emitting sources, and how much warming would come from that growth. They’ve been debating whether more money and lives would be saved than lost by trying to reduce that warming by shifting from carbon-based to non-carbon-based energy sources. They’ve been debating even the nature of scientific inquiry itself—the role of modeling versus that of empirical observation, and the growth (lauded by some, condemned by others) of post-normal science.

And then, voila! In the midst of all that debate, over all those different questions that, together, constitute the debate over CAGW, the vaunted University of California, Berkeley, Professor Richard A. Muller stands up and says, “Global warming is real. End of debate.”

And people—I’ll list them again: the public, the press, and the true-believer scientific community—take him seriously!

Nothing heretofore in the CAGW debate has been more discouraging to advocates of reason than this. Forget about all the flaws inherent in BEST’s methodology, flaws pointed out by a large number of CAGW skeptics. Forget about the fact that Muller announced BEST’s results before the papers issuing from it went through peer review—a strategy environmental journalists by now should recognize for the stunt it is.

Forget about those things. The most stunning and disheartening thing is the demonstration this gives of the widespread incapacity to recognize when someone has conveniently changed the subject and then proclaimed victory.

Ignoratio elenchi. Okay, so it’s a Latin term. Get over it. Comprehend it, make it a normal part of your vocabulary, and be on guard for it.

And if, despite knowing that BEST is simply irrelevant to the CAGW debate, you’re still interested in its detailed errors, see critiques by, among others, Roger Pielke Sr., Anthony Watts here and here, William Briggs here and here, Douglas Keenan, Luboš Motl, and Richard Lindzen and David Douglass.