Last fall, in a series of posts about what I dubbed The Lomborg I made the case that Lomborg was misusing Cost-Benefit Analysis to say that cuts in CO2 emissions will cost more than they are worth. I also added that “I hope we will hear from some environmental economists on this” – and also get statements from those experts listed as signing off on the ” Copenhagen Consensus” – an expert group convened by Lomborg to rank priorities for addressing the major challenges of our time, based on their costs and benefits.
Not that I had anything to do with it but, shortly after that, Nature published a book review by Sir Partha Dasgupta – a well-known and respected economist, that reinforced my point. Which is that, even if you fully accept the tenets of neo-classical economics, Lomborg’s arguments are basically crap. And that’s without even going into the flaws in his argument about expected sea level rise (which has been repeatedly debunked but, without responding to any of his critics, Lomborg keeps repeating the same thing. This post is not a response to him but to all publications that have given him a platform.)
Now we also have some critical words from Gary Yohe – an economist who was a member of the IPCC, and also participated in Lomborg’s “Copenhagen Consensus” project, for which he wrote the principal climate paper, on which Lomborg’s conclusions are based. Responding to a Lomborg article in the Guardian, Yohe says:
But there’s just one problem: as one of the authors of the Copenhagen Consensus Project’s principal climate paper, I can say with certainty that Lomborg is misrepresenting our findings thanks to a highly selective memory.
Lomborg claims that our “bottom line is that benefits from global warming right now outweigh the costs” and that “[g]lobal warming will continue to be a net benefit until about 2070.” This is a deliberate distortion of our conclusions.
We did find that climate change will result in some benefits for developed countries, but only for modest climate change (up to global temperature increases of 2C – not the 4 degrees that Lomborg is discussing in his piece). But developed countries are relatively prepared to handle climate change’s effects – they tend to be in colder areas, and they have the infrastructure to mitigate severe depletion of resources like fresh water and arable land.
That is precisely why our analysis concluded – and Lomborg ignores – that climate change will cause immediate losses for developing countries and the planet’s most vulnerable, millions of whom are already facing challenges that climate change will exacerbate.
Downplaying the threat of climate change allows Lomborg to focus on his claim that “unlike even moderate CO2 cuts, which cost more than they do good, we should focus on investing in finding cheaper low-carbon energy.” He attributes this finding to our analysis as well, but again he overlooks a key element of our work.
Of course the world needs to make significant investments in cheaper, low-carbon energy. But making those investments without also implementing a constraint on emissions would fail to address the problem. …
To make things even more confusing, Roger Pielke in turn cherry picks Yohe’s remarks to say that he doesn’t see where Yohe’s conclusions differ from how they are represented by Lomborg, citing the Yohe et al analysis which concludes “[g]lobal warming will continue to be a net benefit until about 2070.” But he ignores Yohe’s qualification that that only applies to developed countries, and assumes temperature changes within two degrees by that time, rather than the four degree plausible scenario that Lomborg is reacting to, commented on in another Guardian article by Oliver Tickell. Since the expected temperature change by the end of the century under a business as usual scenario is 3.5 degrees, Roger can’t figure out the discrepancy, but if you click the links, you will find that Oliver Tickell was responding to a recommendation made by Bob Watson, the former chair of the IPCC and now Chief Scientific Advisor to the UK Department of Environment, Food and Rural Affairs, that the UK should plan for a 4 degree C change in temperature, which has a 20% chance of occurring by the end of the century.
As Lomborg notes, the IPCC projection is between 1.8 and 6, Celsius. The sea level rise projection is 18-59 centimeters. But he fails to note that the IPCC projections explicitly exclude consideration of “rapid dynamical changes in ice flow”, or melting of the Greenland and West Antarctic ice sheets. Lomborg’s basic pattern is to simply pick conservative or mid-range estimates, without any justification, and to ignore the qualifications. But there are many good arguments as to why the IPCC analysis, and science in general, tend to err on the side of being conservative to begin with. And there is a good argument why even the economic damage estimates such as those presented by Yohe et al are likely to be a serious underestimate, as was explained by Paul Baer, in his discussion of The worth of an ice sheet. All worthy of further comment.
For now, I would simply like to challenge all economists is to get on the bandwagon, and make as big of a fuss about Lomborg as they did about an infamous paper that added up the “values” of ecosystem services to $33 trillion…