March 02, 2010
Daily Caller Interview with Ted Nordhaus
Mike Riggs at the Daily Caller include several quotes from me in an article about climate skepticism. So as to avoid any confusion about my views on the subject, I post below the full text of the extended email correspondence from which Riggs pulled the quotes:
Mike Riggs: Do you see skepticism as a rational reaction to recent news about "climategate," inaccurate studies in the 2007 IPCC report, or criticisms of Dr. Phil Jones?
Ted Nordhaus: You have to ask yourself what you mean by skepticism. Are you talking about skepticism about the relationship between CO2 and global temperatures? Skepticism about whether temperature trends over the last decade are consistent with the predictions of climate models? Skepticism about the relationship between present day natural disasters and global warming? These skepticisms are not the same thing. One can accept the relationship between CO2 and global temperature increases and be skeptical of the predictions of climate models. One can accept that CO2 is warming the planet and even accept many of the predictions of climate models and still be skeptical of the claims that global warming is driving rising disaster losses in the present.
Both sides in the climate debate have conspired to conflate what are many different findings and conclusions from what are many different sciences into a single thing called climate science and then reduce the world to those who accept or deny it. So I think it is fair to say that some skepticism is more rational than other skepticism. I think that the evidence that CO2 is in fact contributing to the warming of the planet is very strong. I think that there is in fact great uncertainty about exactly what that contribution is in relation to other natural and anthropogenic factors (e.g. land use changes, etc.) and that there are huge bandwidths of uncertainty in the predictions of climate models. We should be skeptical of claims, by scientists and non-scientists alike, that we can predict with certainty what is going to happen. We have known since the beginning everything we needed to know to decide that we ought to decarbonize our economies. There are multiple reasons to do this many unrelated to climate change. Whether the right atmospheric number is 350 or 450 or 550 is irrelevant to the fact that prudence would suggest that we decarbonize our economies as rapidly as practicable. Climate science has had nothing more to offer us on these questions for two decades and the continued effort to seek answers to what are essentially political problems through science has been an immense distraction and increasingly a circus.
If the question is public opinion, I think that one should not take any of the polling too literally. The public has always actually understood that there was a lot of uncertainty in climate science and the way that pollsters try to reduce that to "do you believe in climate change" or not or various variations on that question does the public and our understanding of public opinion on the subject a great disservice. For two decades, publics around the world, including the American public, have typically supported action to address global warming by large majorities so long as those actions did not seem too costly or draconian. No amount of new science is likely to change that one way or another. Most folks are willing to accept that climate science is telling us we should do something about global warming so long as that something involves something they basically support doing anyway and they are skeptical of climate science to the degree that climate science is telling them to do something they don't want to do. The declines in acceptance of climate science among Americans predate the current controversy and probably have a lot more to do with economic fears and the rising unpopularity of cap and trade than with any close reading that most Americans are doing of climate science.
MR: Do you think skepticism is just another version of denialism? Is it more or less intellectually rigorous?
TN: As per my earlier response, there is a lot to be skeptical about without denying the basic relationship between CO2 and global temperatures. So you really need to define your terms. If you said that denialism entails denying any significant relationship between CO2 and global temperatures while skepticism revolves around more specific claims about what the long term sensitivity of global temperatures to CO2 is, what the positive and negative feedbacks will be, what the regional and localized climate impacts will be, what the impact upon human populations will be, then yes, I would say that skepticism is more intellectually rigorous. But you really need to define what these various terms, which are more often than not used interchangeably, actually mean.
MR: Do you think environmentalists will be able to work with skeptics in a way that they can't work with denialists?
TN: Again, you have to define your terms. I think there are many people who have been attacked for being skeptics or even deniers who are quite ecologically minded and support a range of far reaching efforts to reduce carbon emissions, transition to low carbon sources of energy, and protect human populations from the impacts of extreme weather and natural disasters. You can be quite skeptical about many of the claims made by environmentalists and prominent climate scientists like James Hansen and still support all of these efforts. So I think environmentalists would be well served to drop the climate science loyalty oaths and figure out how they can work with folks who may not share their assessment of what climate science may be telling us but do support a range of efforts that would have the effect of decarbonizing our economy whether the worst fears about global warming turn out to well founded or not.
MR: Someone else I spoke with also pointed out that the British press has covered climate change much differently than the American press. I know some of that has to do with proximity (U. of East Anglia, for example), but access aside, do you think that Americans would feel differently about climate change if they were reading tabloidy/sensationalist climate coverage?
TN: Probably not. I don't think most Americans are paying that much attention. I think Americans will by and large continue to support efforts in principle to reduce carbon emissions even if they question climate science. But that support will be highly conditioned upon the perceived costs.
MR: Re skeptics: You described several versions, and I think the one I'm going with is the one you described most generously. (..."what the positive and negative feedbacks will be, what the regional and localized climate impacts will be, what the impact upon human populations will be...")
Working off that definition, do you think that more could be done by environmentalists to invite these types of people into conversation? Ellen Goodman famously compared gw deniers to holocaust deniers in 2007, and I think most folks on all sides of the issue would be reluctant to call that helpful.
TN: Yes, the holocaust denier charges are not helpful. There's a pretty big qualitative difference between asserting that 6 million Jews were not exterminated in the holocaust and saying that you don't think CO2 causes global temperatures to increase. Ironically, I think that environmentalists could find lots of common ground even with deniers if they would let go of some of their own orthodoxies. A pretty fair share of deniers are rabidly in favor of nuclear power, the most viable present technology we have to create large amounts of CO2 free energy. So you could start there. But if the only answer in the view of greens is legally binding CO2 caps then they are going to have a hard time enlisting the support of denier or a lot of skeptics. A lot of the craziness about the science has actually come from greens attempting tar anyone who questions cap and trade or similar regulatory strategies to mandate reductions of emissions as anti-science deniers. But there are many reasons to question those policies that have nothing to do with one's assessment of climate science. So enlisting skeptics will require greens to rethink how they want to approach the problem and there has been little evidence to date of openness on that question.