Learning from Lomborg
By Bryan Caplan
There’s a reason why Bjorn Lomborg has been rewarded for writing The Skeptical Environmentalist with a pie in the face. The book’s good, very good – and that’s bound to anger the touchy, gloomy Greens he’s debunking.
The book has few big surprises for me – I’ve been reading the late great Julian Simon for years. (I never met him, though. Let that be a lesson to you to meet everyone you’d like to meet while there’s still time). But few does not mean zero. Lomborg’s most subjectively striking claims:
1. Trees don’t on net produce oxygen.
In the 1970s we were told that rainforests were the lungs of the Earth… But this is a myth. True enough, plants produce oxygen by means of photosynthesis, but when they die and decompose, precisely the same amount of oxygen is consumed… Even if all plants, on land as well as at sea, were killed off and then decomposed, the process would consume less than 1 percent of the atmosphere’s oxygen.
My 4th-grade teacher told me the “lungs of the Earth” story, and I’ve believed it during the subsequent quarter decade. But Lomborg’s claim seems pretty cut and dried. Is he wrong?
2. Indoor air pollution kills about as many people as outdoor air pollution.
In part because “we spend by far most of our time indoors and because our homes have become more tightly sealed since the oil crisis because we insulate them better”:
[I]n the U.S. indoor air pollution is estimated to cause between 85,000 and 150,000 deaths a year compared to between 65,000 and 200,000 deaths caused by outdoor air pollution.
This result is particularly interesting for economists because indoor air pollution is not a negative externality. The people who breathe the air pay for its quality. Reading this makes me want to open my windows more often. And maybe I should have installed a radon vent for my basement after all.
My big question: Is Lomborg’s autobiography for real? Lomborg says he had no sympathy for Simon’s views before he started this line of research:
“I’m an old left-wing Greenpeace member… Honestly, we expected to show that most of Simon’s talk was simple, American right-wing propaganda.”
I don’t have any reason to doubt his story, except that I doubt all stories of this sort. But I would really like a neutral party to check it out.
Who cares? It goes to credibility. If a Danish statistician with strong Green leanings looked at the data and wrote this book, I’m going to get a lot more confident in my environmental optimism. Otherwise, I’ll stay about where I started.