Marc Gunther has a couple offbeat global warming investment ideas. I haven't figured out how to make portfolio investments in lobbyists, my brain locks up when I postulate them as an asset class.
I skimmed "The Population Ecology of Gucci Gulch, or the Natural Regulation of Interest Group Numbers in the American States" looking for ideas, nothing.
The IPCC's Working Group III is meeting this week in Bangkok, they will release the Summary for Policymakers on Friday at the 26th session of the IPCC traveling fun show (these folks sure fly around a lot, Brussels earlier this month, Valencia in November).
This summary, mitigation, will be the one to look at for investment themes, although following IPCC s.o.p., the actual report will be tweaked to conform to the summary and won't be released until October. I'm not kidding about that last bit, summary first, adjust report to fit.
See "Appendix A to the Principles Governing IPCC Work" http://www.ipcc.ch/about/app-a.pdf
"Changes (other than grammatical or minor editorial changes) made after acceptance by the Working Group or the Panel shall be those necessary to ensure consistency with the Summary for Policymakers or the Overview Chapter."