Steven Levitt, Geoengineering, Side-Effects, and DDT

Levitt presented an idiot-proof version of his 'Superfreakonomics' geo-engineering on his blog today.

It's hard not to find his argument compelling, but now it's him who seems to be "willfully misreading" his critics, claiming they're not trying to answer the question: "what's the cheapest way to cool our planet", but rather:

“What is the ‘right’ amount of carbon to emit?” or “Is it moral for this generation to put carbon into the air when future generations will pay the price?” or “What are the responsibilities of humankind to the planet?”

By 'moral', I'm pretty sure the Al Gore's of this world mean, 'what real effects will it have on our environment, health, and lifestyle. But Levitt has twisted the environmentalists' argument into some sort of philosophical argument over whether humanity has the 'right' to leave a footprint on earth at all, an argument that has no bearing on our actual well-being. This puts it at odds with his 'rational', 'economic' way of thinking.

But what if Geoengineering doesn't turn out to be the silver bullet he think it will be? What if it turns out like DDT, that early mosquito incesticide for which a Nobel Prize was won, but then was eventually banned due to its unforeseen harms to the food chain and to real people? DDT was later banned after humanity's brief love affair with it.

If all Levitt wants is research into geoengineering, and it's really as promising as he claims, I don't think a lot of his critics see a problem with that. But as soon as he start to say we can rely on geoengineering in lieu of cutting carbon emission, it starts to seems like he's counting our chickens before they're hatched. How do we know the side-effects of geo-engineering won't turn out to be as bad as those of DDT? Pumping millions of tons of sulfur dioxide into the atsmosphere in particular, seems like something you'd want to be a bit circumspect about. I understand it's already done periodically by volcanoes, but is it really a sustainable long-term solution or just a quick fix to an underlying problem that will get steadily worse if we don't focus on the underlying cause?

I don't know the answer to this question, but I don't see how Levitt's complacency on geo-engineering justifies ditching carbon emissions regulation. What's nice about emissions regulation is 1) it addresses the problem at the source, and 2) it forces polluters to internalize the costs of their pollution, rather than just spilling whatever fumes into the atmosphere they find convenient, despite their effects on everyone else. Obviously, I understand how their higher costs will raise everyone else's fuel prices, etc..., but that just reflects the fact that we're all responsible for the emissions, not just the 'evil energy companies' that we buy our fuel from.