For years here at IER I have been warning Americans that the “consensus science” in the peer-reviewed economics literature doesn’t at all support aggressive political action in the name of fighting climate change. For example, back in 2014 I used the latest climate report from the UN in order to show that the UN’s (then) preferred climate target of 2° Celsius didn’t make sense. Similarly, last fall when William Nordhaus won the Nobel Prize for his pioneering work on climate economics, I mentioned the awkward fact that his life’s work quite clearly repudiated the UN report that came out the same weekend as Nordhaus’ award.
Now because I’m an economist, I understandably focus on the economics literature. But anybody with eyes can see that the claims of immediate climate crisis have been oversold in the natural sciences, as well.
This was obvious in a recent article in the New York Times, written by PhD physicist Sabine Hossenfelder. The title of the piece is, “Is Climate Change Inconvenient or Existential? Only Supercomputers Can Do the Math.” Already this is surprising: could it really be true that climate change is merely inconvenient?! I mean, the BBC is telling us that we don’t have 12 years to act—as Alexandria Ocasio-Cortez (falsely) claimed the UN reports tell us—but in fact we only have 18 months to save the planet. So did the NYT editors screw up with that title?
Nope, the NYT headline is fine. Here is a longer excerpt from the piece by Hossenfelder:
But we don’t know how to solve [the equations modeling the climate system]. The many factors that affect the climate interact with one another and give rise to interconnected feedback cycles. The mathematics is so complex, the only way scientists know to handle it is by feeding the problem into computers, which then approximately solve the equations.
The Intergovernmental Panel on Climate Change based its latest full report, in 2014, on predictions from about two dozen such computer models….While similar in methodology, the models arrive at somewhat different long-term predictions. They all agree that Earth will continue to warm, but disagree on how much and how quickly.
…
In this situation, the best we can do is improve computer models to obtain more accurate, approximate solutions. It is knowledge we urgently need: As Earth continues to warm, we face a future of drought, rising seas and extreme weather events. But for all we currently know, this situation could be anywhere between a mere annoyance and an existential threat. [Bold added.]
The above excerpt—and remember, this is coming from a physicist whose article was vetted by the NYT—is absolutely shocking, in the context of U.S. political debates over climate change. If President Trump or Senator Inhofe had made equivalent remarks, the internet Thought Police would quickly pounce on such “unscientific” denialism.
And yet, the so-called “lukewarmer” position is actually the most defensible, in terms of mainstream climate science. Do not fall for rhetorical tricks when alarmists claim that “we’ve known for over a century that carbon dioxide-induced climate change is real,” because the basic chemistry and physics is not in dispute. As scientists like Judith Curry, and my Cato co-authors Pat Michaels and Chip Knappenberger have been telling the public, the immediate effect of carbon dioxide will not lead to disaster. The predictions of catastrophe are derived from controversial “feedback effects” that arise in certain models, but not in others. The various models are all consistent with the laws of physics, but—as the NYT piece explains—our computers currently have to cut corners, because the climate system is so complex.
Conclusion
I’m not a (physical) scientist, and I don’t even play one on TV. But as a professional economist, I can quite confidently report that the economic models of climate change do not come in the same ZIP code as supporting the aggressive policies touted by recent UN reports. And, as a recent NYT article from a PhD physicist admits, even the physical scientists aren’t agreed that disaster looms. Indeed, climate change might very well just be a mere inconvenience. This type of revelation doesn’t by itself tell us the proper government policy response, but it does tell Americans which vocal activists they should immediately tune out, because they’ve been caught bluffing.
