I’d like to thank Cato Unbound for convening such an extended exchange of views on how to deal with climate change, and for giving me a platform for expressing my views on this subject. I’d also like to thank Joseph Romm, Indur Goklany, Michael Shellenberger, and Ted Nordhaus for their extensive efforts in considering and responding to my essay and subsequent comments. It’s always inspiring to me to see people who’ve devoted so much time, work, and intellect to analyzing hard problems.
Mr. Romm and I in particular have disagreed quite directly about the likely impacts of carbon dioxide emissions, and I’ll just refer interested readers to the series of detailed exchanges between us, and ask them to draw their own conclusions. Rather than use this closing comment to respond to the last round of replies by each contributor (it seems kind of unfair that I would get both “first ups” and “last licks,” as we used to say in Little League), I’d like to try to establish what I think is common ground between us. I think that vigorous but respectful and fact-based disagreement is almost always a precondition for practical progress on complicated issues, but that ultimately some consensus needs to be achieved to get anything done.
It seems to me that all contributors believe that anthropogenic global warming is real and poses a serious risk. We all agree that an R&D program of the type that I have proposed is a component of a solution, and I hope that we all can get behind this idea. I think that we would all support adaptation to weather problems that may arise as a wise investment of resources. Most adaptation measures have the advantage that, in comparison with R&D or mitigation efforts, they can be executed in fairly short order and only in response to problems as they become manifest, and hence would likely have very attractive cost-benefit ratios. Finally, I think that we would all agree that the ongoing efforts to analyze physical and economic trade-offs involved in various proposals through the IPCC and similar bodies are valuable and should be supported. (In fact, I would like to see such processes incorporate case-by-case analyses of the kinds of incremental R&D/technology-deployment ideas that Messrs. Shellenberger and Nordhaus have proposed). Improved science, along with increased structure and rigor in the debate of its implications, should enable further progress.