After the April 2011 severe weather outbreak, we learned that tornadoes behave differently in the South than in the plains. Researchers at the University of Mississippi's National Center for Physical Acoustics have developed low-cost, high-fidelity technology that could help better detect tornadoes by using special microphones.
"These are microphones designed primarily for very low frequency sound, frequencies below what humans can hear," explains Senior Research Scientist Dr. Roger Waxler.
Most of us can't hear sounds below 20 Hertz. But studies have proven that tornadoes emit frequencies much below this level from as far away as 20 miles because they're less prone to interference than high frequencies. These sound waves have been picked up by the microphones in western states.
"There's a focus now to look at the Southeast both because of the tornado damage that's been done and also because it's hilly," adds Waxler. "It's a different environment."
The microphones will be set up in arrays, most of them under domes to reduce wind noise. They've been set up in five other areas in northern Alabama and southern middle Tennessee with five more to go including the one in Georgia. It's the only one planned to be near the Chattanooga area.
The microphones can't replace radars which relay storm information quicker than sound, but if the microphones work in our part of the county they'll be an added tool to help the National Weather Service get even further ahead of the storms to issue warnings.
"If this works, how quickly can we actually make detection and get a warning out," is the challenge, says Waxler.
Walker County Public Relations Director Joe Legge is glad this is happening in his area.
"Walker County is very excited to play a part no matter how big or how small," says Legge.
While the technology was developed at Ole Miss, the microphones are manufactured by a company in Tupelo, Mississippi. The research is fully funded by NOAA (National Oceanic and Atmospheric Administration) and costs Walker County tax payers nothing.
Waxler expects the rest of the microphones to installed by the end of March. They'll measure data for about two months.