Chris —

Thanks for your input. NAS is a great example. You have some other good points, too:

1. We will need a balance of mitigation and adaptation, if for no other reason than climate momentum. Even if we were magically to cut emissions to zero tomorrow, global temperatures, sea levels, storm tracks and the like would continue to evolve for decades. The trick is to balance mitigation costs vs. adaptation costs at the margin. I agree PERC’s recommended mix has way too little mitigation.
2. Do you have any serious studies you can link to support the contention that “global economic growth will turn negative before 2100”? Mainstream models do not predict that. In fact, the scariest models like RCP 8.5 are those that posit continued rapid economic growth as a main driver of rising emissions. I wrote about this a while ago. Comments? This is one case in which I’d love to see a good refutation of my argument.
3. The trickiest parts of administering a carbon tax are not fossil fuels, which, as you say, have point sources and relatively easy to meter carbon content. The harder parts include (a) border adjustments;(b) industrial non-fuel emissions like cement; (c) agriculture; and (d) properly crediting carbon removal and sequestration activities.