July 2000

Taming Tornadoes

Meteorology

By David Graham

During an average year in the United States, some 800 tornadoes injure more than a thousand people. A California physicist believes it is possible to use blasts of microwave energy from a satellite to diffuse developing tornadoes before they can wreak their damage.

Bernard Eastlund, president of Eastlund Scientific Enterprises in San Diego, Calif., proposes using microwaves to heat the cool, rainy downdrafts that form a tornado. According to modeling by Eastlund on supercomputers at the University of Oklahoma's Center for Analysis and Prediction of Storms, about 100 million watts of energy added to the descending air column could disrupt a downdraft that otherwise might spawn a tornado.

Federal Emergency Management Agency (FEMA) physicist Paul Bryant, an expert on tornadoes, thinks Eastlund's idea is practical. "He's got a good concept and has demonstrated in computer models that you can arrest a tornado," Bryant says. Bryant, who is FEMA's adviser to NASA on its efforts to mitigate natural disasters, says the International Space Station would be an ideal vehicle for an initial test that would involve diffusing developing waterspouts over remote sections of ocean.

Not everyone thinks that's a great idea. Dan McCarthy, a tornado expert at the National Oceanic and Atmospheric Administration's Storm Prediction Center in Norman, Okla., cautions that diffusing tornadoes might open a meteorological Pandora's box. "I'd be real careful in trying," McCarthy says. "You may set off another area of thunderstorms elsewhere."