A low probability event

The Annual Meeting of the American Public Health Association is scheduled for New Orleans this November. I'm planning to be there. We may have to change our plans.

This is from an American Public Media documentary that aired earlier this year:

When emergency management officials think about the worst natural disasters that might befall America, San Francisco is always on the list. They say there's a 70 percent chance that a major earthquake will hit that city in the next 30 years and potentially cause thousands of deaths. But they say there's another disaster that could be far worse—and many people don't know about it. The chances that this tragedy will happen are much lower, but the death toll would be staggering. Government officials are trying to figure out if there's any way to prevent it.

The improbable disaster is that a Category 5 hurricane would strike New Orleans. The city lies below sea level, protected by a system of levees and continually drained by enormous, electrically powered pumps. A direct hit from a powerful hurricane will cause the Gulf of Mexico to surge over the levees, inundating New Orleans and surrounding communities to depths of up to 20 feet. The flooded, powerless pumps will stop. The water will have nowhere to go. The city will be destroyed.

This situation has been exacerbated by human activities that changed the flow of the Mississippi into the Gulf, resulting in the continual erosion of marshlands. Over time, this has brought the coast steadily closer to the city, reducing the natural barriers that protect the Big Easy and making the prospect of horrific damage more lkely.

It is now 10:00 am on Sunday, August 28. Hurricane Katrina in the Gulf of Mexico is now a category 5 hurricane, with maximum sustained winds of 160 MPH -- one of the most powerful storms in history. The National Hurricane Service predicts a direct hit on New Orleans, some time early Monday morning. It may not happen -- predictions of hurricane tracks are imprecise, and the storm could also weaken unexpectedly. Nevertheless, that highly improbable event is, as of this moment, very probable. News coverage, by the Associated Press and even the New Orleans Times-Picayune, has been oddly nonchalant. The city is under an evacuation order, and the authorities are predicting flooding, but the possible extent of the calamity is never mentioned.

While we can still hope that the worst will not occur, it is already time to try to draw some lessons from this situation. People are not well-equipped psychologically to deal with prospects of radical discontinuity. Whatever we may learn intellectually, our behavior, both individually and collectively, is much more powerfully shaped by the assumption that our environment will continue to be essentially as it has been. Recent decades in the U.S. have seen massive development on hurricane-prone beaches, and in low-lying areas around New Orleans. The risk to metropolitan New Orleans has long been known, but nothing has been done about it. People just don't seem to accept the prospect of a novel disaster as real.

As we confront the possibility of a worldwide, killer influenza pandemic (discussed briefly here by YT and far more extensively over the months by Revere at Effect Measure, we reflect sadly on this non-intelligently designed human trait. Let's try once again not to learn the hard way.