How long would it take Tybee Beach to turn into a scene like the many we've scene from the Asian tsunami?
"Worst case scenario, probably less than five minutes," said Chuck Watson, a Savannah man who makes his living in the disaster business.
He uses computer models to assess all kinds of environmental hazards. "Earthquakes, tsunamis, hurricanes, tornadoes, chemical spills, nuclear bombs, pretty much if it blows things up and knocks things over, whether it's human or natural, that's in my purview."
He says the computer models he and other scientists use are very accurate at predicting the outcome of natural events.
"They're pretty good. In fact within, about eight hours of the Sumatra quake...we did a projection that a hundred and twenty-eight thousand people would be killed immediately...if you plug in the right numbers, you get the right numbers out. So they're probably accurate to within ten or 15 percent."
In most cases, the models show some warning for coastal residents. A volcanic eruption in the Canary Islands would give us about nine hours. Another seismic event in the Caribbean, four or five hours.
Another scenario involves continental shelf, where sediment can collect. "There's material, sand and mud that accumulates at the edge of the continental shelf," said Watson. "Sometimes it breaks free. It's almost like a snow avalanche."
Computer models predict devastating tsunami waves could result in minutes from such an event, though Watson says the chances of the worst case are about ten or twenty thousand to one.
Watson maintains SatBlog, where you can read his analysis of this and other disasters.