Jonathan Gilligan, Associate Director for Research, Vanderbilt Climate Change Research Network and Associate Professor, Department of Earth and Environmental Sciences, at Vanderbilt University, has written in with some
interesting questions on the thought experiment I posted earlier today. With his permission I reproduce his email below, along with my replies.
Dear Roger,
A couple of years ago, you wrote a very nice paper reviewing the prospective cost of air capture technology. You post today on your blog arguing that decisions whether to accelerate decarbonization of the energy supply don't depend in any practical way on climate science.
If you have time to think about them and reply, I would like to ask three related questions:
(1) Do you similarly think that decisions whether to spend lots of money researching and developing air-capture technology don't depend on climate science?
REPLY: The decision to deploy air capture technology certainly depends upon a judgment that we should "tune" atmospheric carbon dioxide levels to some precise value. My view is that air capture is not a technology that would be deployed any time soon, but we may wish to develop it to keep our options open decades hence. This judgment is based on the possibility that we may want to have a back-up plan in canse conventional mitigation does not work out and we wish to adopt a "brute force" approach.
So, any decision to deploy air capture will certainly require a judgment that doing so is beneficial, and this would come from information produced by climate science. Just as we will want to invest in air capture research in coming decades, so too will we want to invest in continued climate science research. The state of climate science today is already sufficient to justify investing in air capture research.
My post today was about accelerating decarbonization, and to start on that path, we need not depend upon climate science, and those steps make sense for reasons well beyond science. Just because we can justify accelerated decarbonization without depending on climate science does not mean that we may not wish to rely on climate science for future decisions.
(2) Do you think decisions how much foreign aid to give LDCs to help them adapt to climate change depend on climate science? I can see arguments either way: much of the adaptation aid would help reduce vulnerabilities to current natural hazards, as you have pointed out many times; but on the other hand, the magnitude and timing of the aid could be very different if we were looking at sea-level rise displacing 18 million Bangladeshis in the next 50 years vs. no real change from current circumstances in the coming century.
Just so I'm clear: when I talk of the relevance of climate science, I'm talking mostly about what we know today---that AGW is real and that within the envelope of possible/plausible futures, there are truly catastrophic outcomes, although the science can't assign meaningful probabilities to those outcomes and (as you and Sarewitz have argued) is unlikely over the next decade to improve its predictive power significantly. Despite what you write, I can't help concluding that this limited scientific understanding is indeed very relevant to energy and adaptation policy because the quasi-irreversible nature of climate change (unless we quickly perfect air capture) would strongly affect the speed with which we choose to act.
REPLY: No. I do not think that adaptation funding should in any way be tied to climate science. The reason for this is that is virtually every location that experiences climate impacts, climate (and projected future changes in climate) is far less important than the societal factors that drive losses. Simply focusing resources on the places that are most vulnerable to impacts will have large benefits irrespective of how the future evolves over the next half century or so.
Consider your Bangladesh example. Bangladesh is projected to gain land area by 2050. But whether it does or does not I think is less relevant than the certainty that Bangladesh is a poor country with considerable exposure to climate events. Developing adaptive capacity in Bangladesh makes sense on its own merits. As I have argued, with Dan Sarewitz and others, adaptation policies can stand on their own, and recently with Mike Hulme and Suraje Dessai, such polices do not depend upon accurate climate predictions.
(3) Could research on public opinion test your hypothesis and perhaps settle some disagreements surrounding it? It seems to me that many questions about or disagreements over your hypothesis on the relevance of climate science come down in large part to empirical questions of what matters to voters and decision-makers. Do you know whether anyone's doing good public opinion research to test whether voters' (or their elected representatives') support for decarbonizing energy (or the related hypotheses about support for air capture or adaptation) depend on questions pertaining to climate science? And would such research be relevant to the questions you raise?
REPLY: A good part of Chapter 2 of my new book makes the case that there is ample political will for action on climate change, and has been for more than a decade. Public support in the US has been remarkably consistent over that time, even with its periodic ups and downs. At the same time, the public has grown increasingly skeptical about the claims made about climate science, believing that it has been exaggerated by climate scientists. Yet, support for action remains strong. There is plenty of polling data to back up these claims, which I cite in the book. And there is also literature which suggest that appeals to alarm or fear just "won't do it."
There is also a much broader literature on the public understanding of science which argues that knowledge of particular scientific facts does not compel particular actions. See this review article, for instance. So I think that the work in this area provides a compelling body of theoretical and empirical reasons to suggest that support for climate policy depends far less on climate science than many in the debate actually might think.
Thanks for your time and attention.
Thank you as well!
Best regards,
Jonathan