I only linked to the TCS article, because I couldn’t quickly find Dr. Ausubel’s actual work. Here’s a piece on Dr. Ausubel’s website:

http://phe.rockefeller.edu/BrainNotChange/

In case you have trouble interpreting it, it shows we’re currently at a hydrogen-to-carbon ratio of approximately 3-to-1. The extrapolation shows us crossing into a a “methane economy” (hydrogen-to-carbon ratio of 4-to-1) circa 2025-2030. And by 2100, the projected hydrogen-to-carbon ratio is 10-to-1.

Therefore, even if energy usage were to, for example, triple from 2000 to 2100, CO2 emissions would be slightly lower in 2100 than in 2000.

“Say, didn’t TCS “host” Glassman predict the Dow would hit 36,000 back during the tech boom?”

Yes, but that’s completely irrelevant. Jesse Ausubel is not in any way connected to TCS. Jesse Ausubel is the director of the Program for the Human Environment at Rockefeller University:

http://phe.rockefeller.edu/jesse/index.html

It’s clearly wrong, but Dr. Nakicenovic claims that it doesn’t have a substantial effect on the GDP/capita projections beyond 2040 (or maybe even 2030). See Figure 1 of this document:

http://crga.atmos.uiuc.edu/publications/ipcc-sres-revisited.pdf

In any case, the errors introduced by using MER vs PPP are absolutely dwarfed by the likelihood that virtually the entire economics profession (with only occasional exceptions such as Arnold Kling and Robin Hansen) will MASSIVELY underestimate world per-capita economic growth in the 21st century:

http://www.longbets.org/194

http://markbahner.typepad.com/random_thoughts/2004/10/3rd_thoughts_on.html

The Heartland Institute provides this analysis and comment by Ian Castles:

http://www.heartland.org/Article.cfm?artId=12088

“By how much did the IPCC overestimate the likely economic growth of poorer nations over the next century? For poorer nations as a whole to catch wealthier nations in economic output this century would require that average incomes on the entire continent of Asia increase over the next 100 years by a factor of 70 to 1 for the IPCC’s least-warming scenario, and 140 to 1 for its most-warming scenario.”

“Such dramatic economic growth by even a single country–let alone an entire continent–would be unprecedented, notes Castles. Examining growth rates in wealthier countries during their most dynamic periods of economic growth, Castles points out that ‘average real incomes in the United States increased by a factor of perhaps 5 to 1 in the nineteenth century, and average real incomes in Japan increased by a factor of almost 20 to 1 in the twentieth century.’”

Well, Ian Castles, I have surprising news for you: the per-capita GDP of the entire world is going to increase by a factor of ***1000*** during the 21st century.

That will make the errors introduced by MER vs PPP pale by comparison!

P.S. The ***real*** problem in the IPCC TAR analysis is not the projected rates of economic growth, but the ridiculous assumptions about how little the entire world is going to “decarbonize” in the 21st century. It is quite likely that, by the end of the century, the whole world will be operating on either a full hydrogen economy, or nearly full hydrogen economy (with some natural gas use). The idea that we will be burning substantially MORE coal in 2100 than we’re burning now…which is a nearly universal assumption throughout the IPCC TAR scenarios, is ludicrous. It’s completely unsupported by scientific analyses of technological trends, e.g. those performed by Jesse Ausubel:

http://www.techcentralstation.com/021803D.html

That claim is not at all false – but the IPCC scenarios and modelling exercise were more than just a review of the literature. And bad economics is still bad economics no matter how many times people have done it in the past. You may find the paper prepared by Professor Nordhaus for a recent IPCC conference on the topic illuminating: http://www.econ.yale.edu/~nordhaus/homepage/ppp_020805.pdf

Or are you saying that the claim that MER was used in most of the studies reviewed by the IPCC is false?

This is more-so a problem because issues of climate and policy cross so many areas of expertise. A climate scientist is not necessarily a good policy maker or economist. Hence the example of that old canard (by now) of Castles, Henderson, the IPCC and market exchange rates (MER) versus purchasing power parity (PPP). You had (maybe still have) climate scientists staunchly defending an economic proposition that is clearly wrong. There is a nice quote in the recently released House of Lords report on this:
“While the IPCC SRES does indeed make some use of PPP conversions, the IPCC acknowledges that it has used MER conversions in its main work, and it insists on the ‘methodological soundness of the use of MER for developing long-term emissions scenarios’. We found no support for the use of MER in such exercises, other than from Dr Nakicenovic of the IPCC.”