Yesterday, Thomas Schelling gave a seminar on climate change here at the Center for Study of Public Choice. Schelling’s main argument was that lots of resources are going into predicting and understanding climate change but very little thought or resources are going into planning for adaptation.

If Washington, DC, Boston and Manhattan are to remain dry, for example, we are almost certainly going to need flood control efforts on the level of the Netherlands. It takes twenty years just to come up with a plan and figure out how to pay for these kinds of projects let alone to actually implement them so it’s not too early to beginning planning for adaptation even if we don’t expect to need these adaptations for another forty or fifty years. So far, however, nothing is being done. Climate deniers think planning for adaptation is a waste and many climate change proponents think planning for adaptation is giving up.

Schelling mentioned a few bold ideas. We can protect every city on the Mediterranean from Marseilles to Alexandria to Tel Aviv or we could dam the Strait of Gibraltar. Damming the strait would be the world’s largest construction project–by far–yet by letting the Mediterranean evaporate somewhat it could also generate enough hydro-electric power to replace perhaps all of the fossil fuel stations in Europe and Africa.

Schelling didn’t mention it but in the 1920s German engineer Herman Sörgel proposed such a project calling it Atlantropa (more here). In addition to power, damming the strait would open up a huge swath of valuable land. Gene Roddenberry and Phillip K. Dick were fans but needless to say the idea never got very far. A cost-benefit analysis, however, might show that despite the difficulty, damming the strait would be cheaper than trying to save Mediterranean cities one by one. But, as Schelling argued, no one is thinking seriously about these issues.

I argued that capital depreciates so even many of our buildings, the longest-lived capital, will need to be replaced anyway. Here, for example, is a map showing the age of every building in New York City. A large fraction, though by no means all, are less than one hundred years old. If we let the areas most under threat slowly deteriorate the cost of moving inland won’t be as high as one might imagine–at least if the water rises slowly (not guaranteed!). Schelling agreed that this was the case for private structures but he doubted that we would be willing to let the White House go.

If we are going to save cities, especially buildings not yet built, should we not start taxing land today that is under threat of future flood? Act now to mitigate future moral hazard problems. John Nye and Robin Hanson raised this issue. See Robin’s post for more.

It was an enjoyable seminar. At 94, Schelling remains sharp, provocative, and in command of the facts.