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Energy Density

A tornado is the most intense force in nature. That doesn't mean it's the most powerful. In fact, a thunderstorm can be 40,000 times more powerful than a tornado. Then why aren't thunderstorms as dangerous as tornadoes? The answer lies in each storm's energy density.

A tornado may not have nearly as much energy as a thunderstorm, but the energy in the tornado is concentrated into a much smaller area. Imagine you have a hose and are watering a yard. You can spray five gallons of water over the whole yard and not really notice it. If you were to spray a couple gallons in one small section, you would probably flood and possibly start to erode it. That's because the water was very concentrated, like the energy in a tornado.

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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