Claude Prépetit had seen it coming in his figures. He had done the calculations, in millimeters and in centuries, he had calculated the pressure that was building up beneath his feet, and he had estimated the energy that would eventually be discharged. And when the earth finally did shake, and falling concrete ceilings, stone walls and wooden beams killed at least 170,000 people within the space of 40 seconds, that was when Prépetit thought to himself: "This is it -- this has to be a seven."

He had predicted an earthquake with a magnitude of about 7.2 points on the Richter scale, and the actual quake measured 7.0. For years, he had taken precise measurements and performed careful calculations, and he had done his job exceedingly well. When the earthquake struck, he was sitting at home in front of his computer. He jumped up and took shelter in the doorframe, because good doorframes are more capable of standing up to an earthquake than walls, something that Prépetit knows well. In fact, as the Haitian government's official seismologist, he knows everything about earthquakes.

In those 40 seconds, his brother-in-law and some of his friends died. Shortly afterwards, his father-in-law also died. Prépetit survived. After having spent years warning about the possibility of an earthquake striking Haiti, he can hardly be blamed for what happened there. Prépetit, a tall man with a wrinkled face who is wearing sneakers, now says, quite calmly, that the earth beneath Port-au-Prince will shake again, but first it will happen farther to the north. The next quake, according to Prépetit's calculations, will be even stronger, probably measuring about 7.6 on the Richter scale. He predicts that it could happen in 20 years' time, give or take a few years.

Prépetit has divided Haiti into risk zones, based on information his staff has compiled and applied to a map of the country. Seismologists looking at the map can immediately recognize that the most dangerous place in the country is the capital. "We have to make this clear to people, and they have to understand it," says the scientist. "A lot of people have to get out of here."

Nightmare City

The Haitian capital may be tomorrow's deathtrap, but it is currently today's nightmare. The bodies still lying in the wreckage are decomposing in the heat, while the survivors simply step over them. Looters are clearing out the ruined buildings, hunted by police officers on motorcycles wielding pump guns. The hungry survivors fight over every bag of rice tossed down from the trucks of international aid organizations.

The United Nations estimates that 75 percent of the city will have to be rebuilt, and that well over 500,000 people are now living in the streets. The more fortunate of the newly homeless have plastic tarps, mattresses or wooden boards to build tents for themselves. The drone of American Blackhawk helicopters can be heard overhead. The Haitians have been promised $2 billion (€1.43 billion), both for the immediate disaster relief effort and to pay for the reconstruction of the country and its capital. Now the question is how to go about it. There are two possible approaches, one dangerous and the other audacious.

The Haitians could rebuild the capital to look more or less the way it did before the quake, except with more stable official buildings, naturally. That would be enough -- until the next major earthquake. Or they could use Prépetit's map, embark on a bold exodus from Port-au-Prince and build a new capital elsewhere. The latter approach would resemble what the Brazilians did in 1960, when the government moved to the newly built city of Brasilia, deep in the country's interior.

Significant Data

In 2001, Prépetit's prediction that the fate of Port-au-Prince is to be destroyed again and again was confirmed when a group of French seismologists came to the island, bringing along state-of-the-art instruments. Prépetit helped them distribute 30 measuring stations around the country. Then the scientists waited, monitoring their instruments, and eventually the equipment began spitting out data. Using the data, the seismologists could calculate how much energy will be released when there is a sudden shift in the two tectonic plates that come together near the capital, the kind of shift that is likely to happen repeatedly. The only problem is that no one can predict when these shifts will take place. Should Prépetit have spoken up more loudly? And even if he had, could he have convinced the government to do anything? "Resettling hundreds of thousands of people is very expensive and very difficult. Haiti is a poor country. And besides, I didn't know when it was going to happen. What if it hadn't happened for another 30 years?" But now Prépetit wants to talk, and he wants people to listen to what he has to say.

An earthquake already destroyed the city once before, in 1751, and the survivors rebuilt Port-au-Prince. The next major quake came in 1770.