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Hurricane researchers are concerned that another Andrew-force storm might hit the U.S. any time now.
Are we more prepared this time around?
As this ScienCentral News video reports, new technology is helping scientists understand and forecast hurricanes like never before.
Fewer false alarms
While dropwindsondes may have provided earlier warning of just how strong Andrew would become and how much danger people were in, they are also valuable for their ability to help scientists decide when not to call for evacuations or warnings, like when Hurricane Michelle was striking Cuba in 2001.
"There was big concern here in south Florida, and NOAA and the Air Force had the planes out and we were releasing the dropwindsondes," says Michael Black, meteorologist at the National Hurricane Center. "And partly because of the data from these dropwindsondes, we were actually able to forecast the fact that it would not hit Florida, and we didnt have to put warnings up." But without the dropwindsondes, he says, they probably would have.
This has an enormous economic impact. Evacuations cost an estimated $1 million per mile evacuated, according to Black. He also notes that beyond the money saved by this improved technology, less false alarms means a less jaded the coastal population.
"You dont want to have the cry wolf syndrome, where people are evacuating and the storm doesnt hit," he says. "If that happens enough times, people will say, Look, Ive done this before and nothing happened; Im not gonna leave. And the real storm comes, the killer storm, and people are in harms way."
The discovery of wind peaks hundreds or thousands of feet above ground level surprised hurricane researchers, but they also gave an explanation for past storms that had confused scientists. In 1983 Hurricane Alicia hit Texas, and scientists were shocked that it did a lot of damage to high-rise buildings in Houston.
"Wind engineers looked at this and didnt really understand why there was so much damage," says Black. "They didnt know if it was because the buildings werent constructed properly. But we know now from these dropwindsondes that the winds at those levels were much stronger than they were down at the surface. So even a storm that is moving inlandHouston is quite a few miles inlandcan still have much stronger winds."
This revelation has spurred the National Hurricane Center to start a complete reanalysis of the Atlantic Hurricane Database, which dates back to 1851. It could also force certain cities to rethink their evacuation policies. New Orleans, for instance, has a "vertical" evacuation policythat is, people are encouraged to seek safety in tall buildings.
"They need to rethink that policy now," says Black, "and not put them up too high in the high-rises, where the high winds are."