KATHERINE COLE: In the United States, the force of a tornado is judged by the damage to structures. Scientists inspect the damage before they estimate the severity of a tornado. They measure tornadoes on the Enhanced Fujita scale or the EF scale.
Ted Fujita was a weather expert who developed a system to rate tornados in the nineteen seventies. The EF scale is a set, or collection, of wind estimates. They are based on levels of damage to twenty-eight different kinds of structures and other objects. Tornadoes that cause only light damage are called an EF-zero. Those with the highest winds that destroy well-built homes and throw vehicles great distances are called an EF-five.
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BOB DOUGHTY: Some people make a sport out of watching and following tornadoes. They are called tornado chasers or storm chasers. Their work can be seen in the extreme weather videos that are increasingly popular on television and on the Internet.
Some chasers do it just because it is their idea of fun. Others do it to help document storms and warn the public. Still others are part of weather research teams.
Recently, an international team of scientists completed a tornado research project called VORTEX2. More than one hundred researchers traveled throughout America’s Great Plains in two thousand nine and two thousand ten. They used weather measurement instruments to collect scientific information about the life of a tornado. The goal of the project was to examine in detail how tornadoes are formed and the kinds of damage they cause.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25