Tim Worstall, writing at the Adam Smith Institute, notes the tendency of climate scientists to think their expertise extends to macroeconomics:
… What we're getting is people who claim expertise in one part of the problem insisting that said expertise gives them power to determine what should be the answers to other parts of said problem.
Tim’s motivation for this is that Michael Mann, a noted climate scientist, had an op-ed in The Guardian about the Keystone XL pipeline (leave aside why an American climatologist would need to write in a British newspaper about a pipeline the Canadians want). Anyway, here’s Mann:
Now that the State Department has just released a final environmental impact report on Keystone XL, which appears to downplay the threat, and greatly increases the odds that the Obama administration will approve the project, I feel I must weigh in once again. [emphasis added]
The simple fact is this: if Keystone XL is built, it will be easier to exploit fossil fuel reserves large enough to drastically destabilize the climate. …
Again, leave aside why the State Department is doing environmental impact reports. Worstall advocates taking Mann at his word: he’s a climatologist and he thinks this is a big deal within his area of expertise.
… Why must you weigh in again? You're a climate scientist. You work on temperature reconstructions. What on earth do you know about the economics of the oil industry?
And that's what our problem is here. Again, leave aside whether you believe Mann's science or not. Let us just, for the sake of argument, accept it for the moment. Excellent: so he's identified a problem, one that we should think carefully about. The same could be true of all sorts of people who have contributed to the IPCC reports. But the climate scientists are not the people we should be listening to on what we do next. For they've no expertise, not even any knowledge, of the subject that is crucial to what we do actually do next.
Economists know a great deal about what we should do next: Stern, Nordhaus, Greg Mankiw, in fact a goodly portion of the entire profession, would say that you whack on a carbon tax and you're done. …
This is another case of a continuing meme on this blog: Why Is Macroeconomics So Hard? (here’s 151 links on why macro is hard).
One of the main factors is the license taken by people without expertise to publicly express their opinions about macroeconomics.
Does anyone else get that this is just … weird?
I’ll tell you another area where people feel free to do this: sex education in schools.
And don’t you feel strange when you listen to the depth of emotion imparted in the opinions of people who have no special expertise in this area?
But we don’t think it’s weird when climatologists discuss macroeconomics.
And yet, I’m a macroeconomist, and I’ve even taught time series to Ph.D. students in environmental engineering at a highly regarded university who were hugely interested in climate problems … and for the most part I keep my mouth shut.
Here’s some totally basic economics that Mann should be aware of. First, the temperature is less sensitive to carbon dioxide than smokers are to the price of cigarettes. Second, carbon dioxide is less sensitive to economic growth than smokers are to the price of cigarettes.
Both of those have to work together to justify this climatologists economic position: that restricting economic growth is what we need to address temperature.
So reducing temperature by reducing economic growth is not just like getting smokers to reduce smoking by raising the price of cigarettes (say with a tax).
Instead, it's like the cigarettes themselves smoke cigarettes (you know ... cig's-cigs ;)
And you're going to get the cigarettes to stop smoking their cigarettes by getting humans to stop smoking the smoking cigarettes by taxing them enough on the cigarettes that smoke too.
Sheesh. This is worthy of the theological debates in Monty Python’s Life of Brian.