A reader writes:

You've thrice now cited Jim Manzi's arguments about cap and trade, and this last one has really put me over the edge.

While Manzi's arguments on the surface of them look sound, Manzi has been basing his beliefs off two very, very flawed pieces of information. First, he continually cites "an EPA analysis of Waxman-Markey," which is an EPA analysis - of the wrong bill. If you look that analysis was done in April of the as of yet, very incomplete Waxman-Markey bill. Nearly two months of legislative tinkering have taken place since then, and the EPA has came out with a whole new analysis that models the final bill. I have not yet seen Manzi cite it that new analysis, meaning he either hasn't read the EPA analysis of the bill as it actually stands, or doesn't want to.

Second of all, Manzi uses the climate modeling of one Chip Knappenberger, who is a well known compatriot of the climate change denial crowd. Specifically, Manzi claims, based of Knappenberger's work, that Waxman-Markey would only have an effect of 1/10th of one degree. Unfortunately citing a climate-change denier on the effects of the cap and trade bill is about intellectually honest as citing a believer in a geocentric universe on astronomy. 

Also, Nate Silver's recent argument about the fallacy of using GDP to measure the effects of climate-change is right on. As well know, the third world contributes only a very small amount to the global GDP, and most of the third-world happens to also live in areas likely to be hit hardest by climate change. As he points out the 5% global effect of climate change on GDP is equal to the GDP of 81 of the world's poorest countries, or roughly 43% of the world population.

Finally, neither you or Manzi have properly submitted the cost of Waxman-Markey to a proper cost-benefit analysis. Manzi argues that 1% of the American GDP is huge in actual monetary terms - which is true. However, climate change is expected to ding the economy 3%, an even bigger number. As no one besides Knappenberger has so far as I know, done an analysis of the climate effects of the finalized Waxman-Markey, it's relative worth is up in the air. However if it is able to reduce the economic effects of climate change (or the international agreement we can bargain for based off of it) by 1%, then it's worth it.

I agree that Nate Silver, and other analysts, have made good points about GDP and global warming, but Manzi has explained why he used Knappenberger's analysis. I'm not a fan of Knappenberger's work, but I'd like to know how Manzi misused the model, if he did. And why have only critics of the bill done an analysis of the finalized Waxman bill? If the economic argument for the bill could be made, I'd think that climate advocacy groups would have made it by now. Maybe I missed it. I'd love to post it, if it exists.

(Graph via Krugman)


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