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, or EF, scale.
Ted Fujita was a weather expert who developed a system to rate tornados in the 1970s. The EF scale involves wind estimates based on levels of damage to 28 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.
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 popular on television and 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.
A few years ago, an international team of scientists completed a tornado research project called VORTEX2. More than 100 researchers traveled throughout America’s Great Plains in 2009 and 2010. 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.
A film about the VORTEX2 project was released in 2011. The film includes never before seen images of tornadoes.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25