Deep thoughts by Paul Krugman — Spending billions of dollars to fight global warming even if we have no idea if those billions will do anything to prevent global warming is the same as deciding whether or not to carry an umbrella on a rainy day:
So, a few thoughts on uncertainty and climate policy. You might not know this from some discussion, but this has been a major research topic
— Paul Krugman (@paulkrugman) May 2, 2017
See for example here: https://t.co/yMY0M76v6y Much of the discussion gets technical, but I think you can get the gist pretty easily
— Paul Krugman (@paulkrugman) May 2, 2017
Suppose it might rain heavily today. The forecast is uncertain, as forecasts are, although meteorologists do their best.
— Paul Krugman (@paulkrugman) May 2, 2017
So should I bring an umbrella? If I do, and it doesn't rain, I've borne an unnecessary cost. If I don't, and it does, I get soaked
— Paul Krugman (@paulkrugman) May 2, 2017
So two questions. One is probabilities: how likely is that rain. The other is costs: how heavy is that umbrella, how bad being drenched
— Paul Krugman (@paulkrugman) May 2, 2017
Climate change is the rain; climate policy the umbrella. What do we know?
1. Climate change could be really, truly, civilization-ending bad
— Paul Krugman (@paulkrugman) May 2, 2017
2. Mitigation policy is NOT hugely costly. We have lots of evidence and experience: pollution control done well not at odds with growth
— Paul Krugman (@paulkrugman) May 2, 2017
And the usual record is that market-based stuff — cap&trade or taxes — ends up much cheaper than expected. Check history of acid rain
— Paul Krugman (@paulkrugman) May 2, 2017
Oh, and renewable technology has made action even cheaper than optimists imagined. So uncertainty is NOT a reason to do nothing
— Paul Krugman (@paulkrugman) May 2, 2017
On the contrary, it makes the case for climate action stronger. Anyone saying otherwise either hasn't thought it through or has an agenda
— Paul Krugman (@paulkrugman) May 2, 2017
Case closed!
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