A new research has claimed that the sounds which are a prelude to tornadoes can be useful in predicting the time and location of their attack. The scientists have conducted a few experiments to narrow down the reason for those mysterious rumbles. The knowledge will help improve the warnings issued for storms.
A new study about the reasons for rumbling before the storms was presented in Seattle at the Annual Meeting of the American Physical Society’s Division of Fluid Dynamics. The sounds are below the hearing limit of a human ear.
Dr. Brian Elbing from Oklahoma State University and his team were behind the research. According to them the existence of the rumble has been known for decades, but differentiating the sounds of a tornado and other weather characteristics has been difficult. The lack of understanding of the reason has been a big problem. They also feel a renewed interest in the subject and the study will be useful for hilly areas.
The team experimented with a microphone fitted in a dome that has four openings. The microphone used was capable of capturing low- frequency sounds. Three of such domes were arranged at a distance of 60 meters from each other in an equilateral triangle. The setup allowed the researchers to filter out the wind sounds, offering them an idea about the size of the tornado and the direction. A sound frequency of 10Hz indicated a small tornado while the frequency of 1Hz indicated a very large one.
Elbing and his team picked up an audio clue of a tornado which was not even received by the radar. They observed the signals 8 minutes before the formation of the twister in Oklahoma recently. Four minutes before the tornado hit, a clear signal was also detected. The setup detected the Oklahoma tornado from a distance of 12 miles. But once the technique is advanced, it will be able to work over larger distances.
According to tornado expert Dr. Harold Brooks from US National Oceanic and Atmospheric Administration, a large-scale experiment needs to be undertaken and many questions should be answered before an accurate approach is utilized. Dr. Brooks was not associated with the experiment done by Elbing and his team.
Tags : Tornado, Tornado Sound,