Earlier, I discussed my desire for a more thorough accounting of the impacts of climate change. It seems a recent government report has provided these estimates, at least for the US.
And good news – it's only a 10% reduction in GDP by 2100!
I know the news story says this would be a nightmare, says it's in opposition to Trump administration policies of deregulation, etc. etc.
But that's an amortized 0.1% GDP growth haircut over the intervening 82 years (approximate value over the range of 2-4% average annual GDP growth – this squares with the 72 rule-of-thumb too, if you don't want to pull up a spreadsheet). It would be hard to imagine an effective government anti-climate change policy being that cheap. To stop global warming, real sacrifices are needed, and going from 3.4% year over year growth to 3.3% is not a sacrifice on the same scale.
The level of sacrifice some people want Americans to experience – largely to benefit very poor third world countries – may actually be cheaper to buy with cash. Paying for it in long term GDP growth suppression has massive downsides. If the United States decided to stop global warming, it's very possible our effective foreign aid budget truly would be the majority of government costs (instead of being tiny and only having the reputation of being huge – is this a case where popular misconception captures a basically correct intuition?).
I continue to believe the more interesting costs are that of increased risks. I keep hearing about increased chances of mega-storms, mega-drought, etc. Where is the discussion of existential risk to human life? What's the chance more than 10% of the population dies suddenly? Those are the costs we can't just pay to avoid, and yet (somewhat inevitably) these costs never end up in the calculations.