Friday, October 09, 2020

Can Anyone Do Arithmetic?

My current minor irritation is Gavin Newsom, governor of California. He keeps saying things that imply that California needs to reduce its CO2 output in order to reduce global warming in order to prevent future forest fires.

I think it dubious that warming, about a degree C in the U.S. (I don't have figures for California) over the past century plus, has anything to do with the forest fires, but put that aside. Total global warming since it started c. 1913 has been about 1.4°C. The IPCC believes the rate has increased — suppose it is now three degrees a century. The population of California is about 1/200th of the world population, the GNP about 1/40th of the world GNP. I don't have data on CO2, so will guess it is 1/50th of world CO2 output. If California cuts that in half, it reduces world CO2 output by about 1%. Over a century, that might reduce warming by something like .03°c. All calculations are back of the envelope approximations and I know that not all functions in the world are linear, but that's enough to give us some idea of the scale of the effect.

Actually, I'm not so much irritated at Newsom — I expect politicians to be demagogues. I'm irritated at the rest of the world, all of the media and all of the people who take blatant nonsense seriously either because it is says what they want to hear or because they cannot be bothered to do arithmetic.

Trump is a demagogue too, but at least people call him on it.


J. said...

The premise of Newman's argument is that every jurisdiction has a responsibility to do their part to fix the problem, not that their individual contribution alone is going to fix the problem.

Cathy Raymond said...

Ah, yes, they call Trump on demagoguery. But they do it to try to take him down, not because they give a damn about his errors, which shows in the way they sometimes distort what he actually does saw.

Alan d said...


David Friedman said...

Checking online figures for CO2 output, the U.S. produces about 14.5% of world CO2. California produces about 7% of US energy related CO2. If the percentage of all CO2, for which I didn't find a figure, is the same, that means California produces about 1% of world CO2, even less than I was guessing.

David Friedman said...

Has Newsom ever publicly said that the reductions he proposes for California will have no significant effect on climate change, except to the extent that they persuade many other jurisdiction to make similar reductions? I haven't seen anything along those lines. Everything I have seen seems designed to imply that the reductions themselves will matter.