A commentor asks what I think is wrong with Bjorn Lomborg. Here's my answer, from the archives:
Skepticism Toward the Skeptical Environmentalist: Archive Entry From Brad DeLong's Webjournal : I cannot be the only economist who was disappointed by Bjorn Lomborg's column in the New York Times on Monday, August 26 . Lomborg makes a number of good points: it is definitely the case that we are pumping enough CO2 and other greenhouse gases into the atmosphere to warm the earth; that many of our environmental problems are the diseases of poverty, early industrialization, and the absence of democracy; that the Kyoto Protocol would be hideously expensive; that it would delay the warming trend for a decade at most; that projected temperature rises up to 2100 are bearable; and that it would almost surely be better to spend the resources that would be sucked up by the Kyoto Protocol on third-world public health and infrastructure instead.
But as I read I kept waiting for another shoe to drop, and it did not. It seemed to me that Bjorn Lomborg's argument was radically and dangerously incomplete. It seemed to me that there were three more critical points that Bjorn Lomborg desperately needed to make, but did not. And because he did not it seemed to me that the net effect of his piece was not to reveal wisdom, but to darkeneth counsel.
So let me make these three missing points:
First, climatologists' model-based central projections of the effects of global warming over the next century are just that: model-based central projections. There is enormous uncertainty about what will happen. It might be the case (although most scientists would bet heavily against it) that our pumping CO2 into the atmosphere will have little effect on climate--that the CO2 will be quickly absorbed into the oceans and terrestrial biosphere (making gardening much easier), and that any residual warming will be largely balanced out by the cooling effects of industrial soot. It is likely to be the case that the central projection of a 4 to 5 degree Fahrenheit warming over the next century will be roughly accurate. It might be the case that something horrible might happen--bubbles of methane trapped beneath the sea floor being liberated to greatly increase the greenhouse effect, global warming disrupting the Gulf Stream and causing a local cooling in Europe that would give Rome the climate of Oslo and produce 400 million Europeans anxious to move someplace else. The central projection of the effects of global warming over the next century looks bearable, but the extreme possibilities may well not be. Any approach to dealing with global warming that does not create the capability for massive and swift action should things be worse than currently expected is fatally flawed.
Second, those who will suffer from global warming are largely in the global south. If global warming does (say) increase the magnitude of major typhoons and does raise the sea level a bit, by the latter part of this century more than 100 million people in the Ganges delta will be at risk of drowning if a high tide accompanies the storm surge of a major typhoon in the Bay of Bengal. The managers and shareholders of companies like Halliburton that will gain from inaction on global warming are a different and distinct group from the tropical peasants who stand to lose their health and their lives. Any claim that "instead of Kyoto we should be doing X" has to be accompanied by a plan to actually do X. Otherwise, the claim that inaction on global warming enhances world welfare is likely to be very false indeed, as it is hard to believe that on the scale of human happiness higher incomes in the global north will outweigh nastier, more brutish, and shorter lives in the global south. It is one thing to say that the resources the Kyoto Protocol wants to use to fight global warming could be used to provide first-class public health and economic infrastructure to the global south. It is another to say that these resources, instead, will be used to get every American household a second DVD player and every tenth American household a power boat.
Third, global warming produced by a fossil fuel-burning civilization may be bearable and managable up to the end of the twenty-first century, but the warming trend is unlikely to stop there. Humanity will have to move to greenhouse gas-free industry at some point unless you want to see temperatures rising not by five but by ten or fifteen degrees. We need to start doing the research and industrial development now so that countries developing in 2050 can be offered an attractivge choice of greenhouse gas-free technologies as they industrialize. We don't want the climate in the twenty-second century to be shaped by an industrial China that in 2080 is still burning its brown coal, do we? So Lomborg's argument has to be a call not for inaction, but for rightly-directed action on global warming--which means a lot more money spent starting today on developing the technological alternatives we will need to have available for the end of the twenty-first century.
How do these three points change Lomborg's argument? He may well still be right that inaction on control of greenhouse gas emissions over the next twenty years is the best policy--but that claim needs a footnote warning that we need now to build the institutions and technologies necessary to take swift action if it turns out that things are worse than expected. He may well be right that the resources that Kyoto would suck up would do more for human welfare if spent creating a more human world by boosting public health and economic infrastructure--but that claim needs to be accompanied by a plan to make sure that these resources are devoted to their best alternative use in the global south. "Would" cuts no ice here. "Will" does.
And, most disappointing of all, is Lomborg's failure to even mention the importance of technological development. If it is the best policy to wait for a technological fix to the problem of global warming, then we need first to fix our technology so that it will be able to do what we ask of it when we need it.
It's not my field of expertise, but as a card-carrying economist I can't help but think that Lomborg is probably right when he condemns Kyoto as a low-value use of our precious wealth--as something that would be largely ineffective at fighting global warming and also so expensive as to foreclose options to do other things that would be more useful. Lomborg's flaw, however, is that he doesn't spell out what the "other things" we should be doing are. And that's what he needs to do if he wants to advance the ball.