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You may be interested in a recent paper by Carleton et al., which addresses some of the issues you raise, such as the relation between temperature and income:

https://academic.oup.com/qje/article/137/4/2037/6571943

One takeaway from that paper is that there is a lot of uncertainty.

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I actually refer to Carleton et. al. in my critique of Rennert because they seem to have avoided two of the three problems I find with Rennert's calculation of the cost of temperature-related mortality and come up with a much lower figure.

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Here's something that seems to get lost as well: even if carbon dioxide production is as bad of externality as thought, consumption of energy is not an externality. It will always be the case that people will try to lower their gasoline, heating, cooling, and electricity bills. It becomes an even more important point when you realize that reducing energy consumption is correlated with so many other aims. Building a well insulated home isn't just good for lowering your bills. It's good for reducing noise and drafts. This is true of a lot of things too. I don't elect for paperless billing and pay my bills online to save paper. I do it so I don't have to keep track of files or go to the effort of mailing a check. I'm not interested in solar power because of the environment. I'm interested in solar because some of the nicest locations to live on lakes don't have utilities in place. I think I had heard you speak in a talk about how fast real estate is replaced, so maybe I'm touching on that point.

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A more general point along these lines is that how much an externality distorts decision-making depends in part on how much of the cost is not an externality. If I receive 90% of the benefit of doing something I will make the right decision unless the cost is between 90% and 100% of the benefit since if it is more than 100% I won't do it and shouldn't and if it is less than 90% I will do it and should. I make the wrong decision only if it isn't very wrong because benefit is only a little larger than cost.

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OK, I have to say it, with regard to your first and second paragraphs: you seem to have an awful lot of confidence in your own beliefs about climate change, and you are no more of a climate scientist than I am. You might well maintain that you have evaluated the evidence for yourself, but I haven't seen signs that you've read really widely on the topic. You appear to know somewhat more than the average true believer, whose "evidence" is basically "this is what people in my tribe believe", but on the other hand, so does everyone else I'll take the time to interact with on the subject.

I'm not saying you are wrong, though I wouldn't rate the chances of you being right at more than 10%. I don't have the search skills or the academic journal access to have very specific opinions myself, except for the obvious - most people communicating on this topic have strong motivations *other than* a desire to develop the most accurate possible understanding and predictions. In *some* cases, they *also* have a strong desire to find and present truth.

What I see from you always looks like cherry picking sources with a goal of convincing others of what you already "know" - climate change is no biggie, and may in fact be advantageous overall. What I see from other sources mostly looks like similar pre-informed attempts to convince people of the opposite, which is one reason I continue to subscribe to your blogs - at least you point out different sources, and (as in this case) sometimes produce critiques of sources others are treating as gospel truth.

With regard to your final paragraph - science proceeds by producing and correcting errors. Bad predictions aren't a sign that the process as broken - they are an opportunity for someone to make their name by critiquing the errors, and producing better predictions. Or to attempt this, and instead produce even more egregious results; science doesn't move forward in a straight line.

I don't expect *Nature* or its reviewers to be particularly good *at economics.* AFAIK, that's mot their field. If that article is in fact an amateurish attempt at cross-discipline work by people lacking much experience in one of the relevant disciplines - which is what it sounds like from your description - that sounds like the normal scientific publication process at work.

I was finding similar crap in 1979 as an undergraduate, reading medical journals on the subject of psychological disorders. (Some of those MDs demonstrated less knowledge of psychology than an undergraduate psych major was expected to demonstrate in their essays.) Eventually people figured out a lot more about the biology/medicine underlying the specific psych conditions I was writing about, though they still aren't fully understood or entirely reversible. But it took a fair amount of time, not moving perceptibly during my four years as an undergraduate.

I think it's a good sign that people are even trying to make financial predictions about climate change, and doing so at even a slightly more granular level than "more carbon improves growth of some crops, therefore all will be wonderful" or "some current agricultural zones will become unusable, therefore we're all going to starve".

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I don't need expertise in climate science, because I accept the conclusions of the body of the IPCC report, and it is reasonably clear on internal evidence, especially the Summary for Policy Makers, that inasmuch as the report is biased it is biased in the opposite of my direction.

That would be relevant to a comment on my earlier post, but my first two paragraphs in this post have nothing to do with whether my beliefs about climate are correct, they are an argument for why other people should repose less confidence in their beliefs. The evidence I offer is not about climate change but about population growth.

Neither the authors nor the reviewers of _Nature_ have to be good at economics to realize that medicine is getting better and that better medicine results in fewer people dying from medical problems. Nor to realize that the increased income they are predicting in their model will make people better able to protect themselves against bad weather.

Do you think that someone who calculates costs for the next three centuries while ignoring the effect on costs of technological change is merely ignorant of economics? Isn't that an error that should be obvious to anyone who thinks about the question for more than five minutes, especially someone with the job of evaluating the paper?

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This sentence is somewhat unclear; I think it could benefit from a comma after "at" -- "...the costs they look at, there are other..."

"My point is not that Rennert’s figure for the cost of carbon is too high; although the authors exaggerate the costs they look at there are other costs that they do not include in their calculations, possibly because they had no way of putting numbers on them."

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