It’s not just Bill Gates who’s suddenly looking less panicky and more sane on global warming. Nor just Michael Shellenberger, who in 2007 coauthored an apocalyptic book Break Through: From the Death of Environmentalism to the Politics of Possibility with Ted Nordhaus, nephew of Nobel Prize-winning economist William Nordhaus, and is now a scathing critic of climate hysteria. It’s also now Nordhaus the nephew who’s repudiating his own youthful alarmist views as “hyperbole”. We’re a bit late on this one because he first clearly explained his apostasy back in August. But he’s back at it, and it’s a powerful illustration not only of how people might move from confusion to clarity, but also of the fact that climate alarmism was never a hoax for the vast majority of advocates and followers, but a sincere error. As we ourselves said with what might have seemed bizarre optimism back in June, for all its apparent momentum climate alarmism was actually on the verge of collapse because it was becoming intellectually unsustainable. Evidently an increasing number of alarmists actually agree.

Incidentally William the uncle Nordhaus is famous for making the case for carbon taxes to reduce emissions, which politicians love. Though he also insisted that such taxes must replace a hoorah’s nest of regulations not sit on it, which politicians hate. Maybe he too will say actually it doesn’t really matter, there’s no crisis. Along with a great many others.

For now Nordhaus the nephew, like Gates, is still what one might call a social alarmist, renouncing hysteria while continuing to believe in man-made climate change and covering himself by expressing unease with dimwitted “right wing dismissals of climate change”. But now that admitting to doubts is becoming socially acceptable, give him a bit more time and he may well become fully one of us dreaded skeptics. And who knows who might be next, but we predict it will become hard to keep track as this trickle turns into a flood. Not of repentant scammers, but of people who have changed their mind and are no longer intimidated into silence.

In an updated Free Press version of his summer recantation, Nordhaus admits that:

“I used to argue that if the world kept burning fossil fuels at current rates, catastrophe was virtually assured. ‘The heating of the earth,’ Michael Shellenberger and I wrote in our 2007 book, Break Through, ‘will cause the sea levels to rise and the Amazon to collapse and, according to scenarios commissioned by the Pentagon, will trigger a series of wars over the basic resources like food and water.’ I no longer believe this hyperbole.”

What’s interesting, especially if you’re one of those prone to the language of “hoax” and “scam” and “grift” and “fraud”, is that Nordhaus does not explain why he decided to stop being an evil liar and go to the cops. He does admit to some unattractive PR decisions by the alarmists including this one:

“In the late 2000s, the climate advocacy community figured out that framing climate change as a future risk would not prove politically sufficient to transform the U.S. and global energy systems in the way that most believed necessary. And so the movement set about attempting to move the locus of climate catastrophe from the future to the present, framing extreme weather events not only as harbingers for future catastrophes, but as fueled by current climate change.”

But then he offers this key passage:

“The reason for my shift in opinion wasn’t only that [Roger Pielke Jr.] had produced strong evidence that undermined a key claim of the climate advocacy community. It wasn’t even witnessing Pielke’s cancellation, which was brutal. It was, rather, that I came to understand why you couldn’t find a climate change signal in the disaster loss data, despite close to 1.5 degrees of warming over the last century.”

Came to understand. Saw the light. As the bit about RPJ’s “cancellation”, the kind of slow then sudden process whereby you notice that your side is arguing in a nasty way and discomfort that builds until it crosses, yes, a tipping point and your Gestalt shifts, you see what you had not before, that it’s not because they’re so passionate, it’s because their underlying argument is wrong and they must use might as a substitute for right.

So here’s one of his reasons:

“what determines the cost of a climate-related disaster is not just how extreme the weather is. It is also how many people and how much wealth is affected by the extreme weather event, and how vulnerable they are to that event. Over the same period that the climate has warmed by 1.5 degrees, the global population has more than quadrupled, per-capita income has increased by a factor of 10, and the scale of infrastructure, social services, and technology that protects people and wealth from climate extremes has expanded massively. These latter factors overwhelm the climate signal.”

Duh, you might be tempted to say. But a lot of intelligent people don’t yet get it, and other intelligent people took a while to. So, again, Nordhaus isn’t deciding to stop lying. He’s changing his mind because the evidence has persuaded him. As with his second big reason:

“anthropogenic climate change is a much smaller factor at the local and regional scale than natural climate variability. Some climate scientists have pointed to anomalously high surface and ocean temperatures as evidence that warming may be accelerating, perhaps even faster than models have suggested. But even in the case where climate sensitivity proves to be relatively high, additional anthropogenic warming is an order of magnitude less than the oscillations of natural variability.”

Again not a crisis of conscience. A subtle but dramatic intellectual point. And he goes on to discuss how he clung to the tail of apocalypse, in a figuratively literal way. As he had put it in August:

“The sting, as they say, is in the tail, meaning so-called fat tails in the climate risk distribution.”

In case you don’t do statistics a lot, what he means is that even if the curve of probabilities is almost all down in the safe zone, there can be a very narrow set of possible outcomes going out to the right on the chart that are completely catastrophic and it’s not prudent entirely to discount them. Still, you keep thinking. And Eureka:

“But like the supposed collapse of the Amazon, once you look more closely at these risks they don’t add up to catastrophic outcomes for humanity.”

In his October piece he makes two further points we think worth quoting if only for mordant satisfaction on this question:

“Why do so many smart people – scientists, engineers, lawyers, and public policy experts, all of whom will tell you that they ‘believe in science’ – get the science of climate risk so badly wrong?”

The first reason for this phenomenon is embarrassing:

“highly educated people with high levels of science literacy are no less likely to get basic scientific issues wrong than anyone else when the facts conflict with their social identities and ideological commitments. Yale Law professor Dan Kahan has shown that people who are highly concerned about climate change actually have less accurate views about climate change overall than climate skeptics, and that this remains true even among partisans with high levels of education and general science literacy. Elsewhere, Kahan and others have demonstrated that on many issues, highly educated people are often more likely to hold stubbornly onto erroneous beliefs because they are adept at rationalizing their ideological commitments.”

Oh dear. And the second is worse:

“there are strong incentives to overestimate climate risk if you make a living doing left-of-center climate and energy policy. The capture of Democratic and progressive politics by environmentalism over the last generation has been close to total. Meanwhile, the climate movement has effectively conflated consensus science about the reality and anthropogenic origins of climate change with catastrophist claims about climate risk, for which there is no consensus whatsoever.”

Awkward, infuriating, and creating the temptation to rant and rave about plots. But when more and more people start explaining how they once believed something they now conclude is wrong, and outlining the intellectual path they took from error to lucidity, the logical conclusion is that they were mistaken, not malign, that it’s not a hoax but a confirmation of the key historical principle that ideas matter, and grifters and hoaxers are ephemeral and adaptable free-riders on big mistakes.