Audio Transcript:

Lisa Mullins: Powerful storms such as Sandy threaten coastal defenses around the world. At the same time, sea levels are rising around the world, and all credible forecasts are for them to continue to rise. The only disagreement is over how fast that rise will be. Geophysicist Klaus Jacob has written extensively about rising sea levels and how they endanger global infrastructure. Jacob is a senior research scientist at Columbia University. He says the so-called "super levees" used in Japan offer important examples about the possibilities and the limits of using engineering to counter the forces of nature.

Klaus Jacob: A super levee is a very massive structure with very wide top where you can actually build a road on. The Japanese have built such super levees, in which, actually, highways run; and you can put even some businesses on that structure. So, the structure is not only a protection for the lowlands behind it; it becomes, actually, a place where livelihoods can take place. Not just for transportation, but you can have little shopping malls and other businesses along it.

Mullins: It sounds like putting a highway or a business on top of a dam.

Jacob: That's exactly what it is.

Mullins: So, how good are these super levees at guarding the infrastructure?

Jacob: They are good for a finite lifetime, and that's the problem with these engineered solutions as sea-level rise keeps going, because not only will the oceans get warmer and continue to expand, but also with a warmer atmosphere, ice will melt in Greenland and Antarctica that will flow into the ocean and contribute to sea-level rise. And therefore, sooner or later they cannot function as a protecting engineering structure. We have seen that already; for instance, when the levees and pumping systems were not kept u in New Orleans, we had Katrina Hurricane in 2005: a catastrophe.

Mullins: Let me ask you one other thing. This is about Bangladesh, a developing country which is particularly vulnerable, but also a place where there have been rather ingenious ways that local people have found to protect the infrastructure there.

Jacob: Bangladesh is a developing country that gets flooded from the typhoons from the ocean side and from the rivers from the other side. So, they have been ingenious: they've built levees and they've built shelters on the levees They come in two forms: some are designed in concrete structures where the entire village can go during a typhoon, or they come in form of trees on the levees where they can climb in the trees and survive a few hours in the trees before the waters recede. That is the cheap version of ingenious protection of the population.

Mullins: How relevant are all these solutions to what the United States is facing right now with Hurricane Sandy?

Jacob: They have two choices. One, we spend a few billions of dollars in any given city to protect us, or we will suffer from incurring a hundred billion dollars from a storm like this or stronger in the future.

Mullins: A hundred billion dollars from what kind of damage?

Jacob: From a hundred-year storm, you can expect damages on the order of fifty to a hundred billion dollars, not millions.

Mullins: Do you, yourself, Klaus, in closing here, see Hurricane Sandy not just as a disaster but also as kind of a wakeup call?

Jacob: While we had one wakeup call last year under the name of Irene, we got away with less than we will most likely incur from Sandy. The question is, "How many wakeup calls do we need in order to get out of our snoozing, sleeping, dreaming warning attitude?" We have to get into action. We have to set priorities and spend money. For every one dollar invested in protection, you get a return of four dollars of not-incurred losses.

Mullins: Thank you. Klaus Jacob, geophysicist and senior research scientist at Columbia University. Thank you again.

Jacob: You're welcome.