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Energy Density

A tornado is the most destructive natural storm. You might think that this also means that tornadoes are the strongest storms; that's not the case. In fact, a thunderstorm which produces a tornado can have 40,000 times more energy than a tornado! Then why are tornadoes so much more destructive than thunderstorms?

Tornadoes have a greater energy density than thunderstorms. They don't have as much energy but the energy they do have is packed into smaller spaces. Another way of thinking about this is with rocks and feathers. A bag of feathers might outweigh a rock, but put them both in water and the feathers will float while the rock sinks because the feathers are less dense. Tornadoes are so destructive because they strike a very small area.


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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA