Prompted by PB I read Gambling with Civilization by Paul Krugman, which is a review of The Climate Casino: Risk, Uncertainty, and Economics for a Warming World by William D. Nordhaus. I haven’t read the latter.
The Climate Casino is in no sense the work of someone skeptical about either the reality of global warming or the need to act now. He more or less ridicules claims that climate change isn’t happening or that it isn’t the result of human activity. And he calls for strong action: his best estimate of what we should be doing involves placing a substantial immediate tax on carbon, one that would sharply increase the current price of coal, and gradually raising that tax, more than doubling it by 2030
And so I want to know, “how strong is this strong action”? A carbon tax is good, obviously, but Shirley Nordhaus is a touch more specific than “sharply increase the current price of coal”, so why can’t Krugman be? K continues Some might consider even this policy inadequate… to which the obvious answer is: “how can I possibly know whether its adequate or not, you bozo, unless you tell me how big this tax is?”
it turns out that the rate at which you discount the distant future doesn’t make much difference to optimal policy
Well, that’s fascinating, and rather surprising. Especially given all the fuss over Stern’s numbers – an insight like that would be a major change to the discourse. Obviously K will go on and tell us how this comes about. Ha ha, fooled you – or more likely I didn’t – K just notes this point and moves on. WTF?
K says that N says “there will be mounting costs as the temperature rise goes beyond 2°C”. Again, this is irritatingly vague, and it isn’t clear if there are costs, but they go up sharply post-2°C, or if small net benefits turn into costs post-2°C. Perhaps its not desperately important: the focus is on large changes; and anyway, N isn’t trying to say anything startlingly original at this point. K/N both agree that the std.textbook_method for dealing with emissions is pricing emissions, and are happy with “a carbon tax and/or cap-and-trade”. N says direct regulation is a poor choice; K acknowledges that, but then in his own voice half-argues for regulating coal-fired power stations, on the grounds of political feasability. I’m dubious, as before.
What’s our target for limiting T rise? [Note that there is some dissonance between that question and a carbon tax, which K doesn't mention, so I don't know if K does.] “The scientific rationale for the 2°C target is not really very scientific” says N, but you can sense that K doesn’t really like this.
K wonders who is the target for N’s book. As he says, all the sane folk already agree, and the wackos aren’t about to be convinced by rational argument. There is, of course, a failure in self-referentiality there, because one could say exactly the same thing of K’s review. Given his disappointing vagueness about rather important details, its clearly not intended for the numerate.