An interesting turn overall in the afternoon Science Skeptics forum: speakers moved from chilling analyses of future climate catastrophe to a frankly optimistic presentation that the solutions may yet be found.

Drs. Prothero and Fagan presented historical trend lines that are fairly terrifying if you follow the logical extension of their climate graphs. But Dr.Gregory Benford addressed possible innovations—methods by which humankind can take charge of the earth’s climate on purpose, instead of just screwing it up by accident. We’re trying to track him down for a podcast that will explain his most fascinating proposal – broadcasting “UVB Chaff” into the upper atmosphere to deflect ultraviolet radiation.

After a break, Jonathon Adler challenged government’s ability to participate productively in regulating the market (see separate post) and Dr. Gregory Arnold set out a quite optimistic description of how carbon trading may well engage the private sector in helping to find the best and most cost effective mechanisms to reducing greenhouse gas production. His, conclusion, though, was still a little frightening: the Kyoto targets are laughably inadequate and, so far, it is impossible to engage the U.S. government even in that lame attempt. Alas.

The final speaker of the afternoon was Dr. Paul MacCready, whose company AeroVironment is an exciting innovator in alternative energy transportation solutions. Check out his website.