Weather
DK Publishing
VHS Tape
(DK Children, Aug. 1, 1996)
It surrounds us everyday effecting our moods and livelihoods, yet we can't control it and can hardly predict it. Sound like a riddle? The weather often seems that way as we learn more about frost, fog, hail, rain, snow, wind and thunderstorms in the Dorling Kindersley Eyewitness Video: Weather. It is the sun that drives the weather, and Aztec Indians used to offer tens of thousands of human sacrifices to assure that it would rise and set every day. Weather occurs in the troposphere, an eight-mile thick layer above us that is never still. As demonstrated in the video by the latest in computer animation and state of the art 3-D graphics, when the sun heats the troposphere the complex interaction between heat and gasses gives us weather. Among his many other contributions, Aristotle invented meteorology and we have been studying patterns in the weather ever since. Today, newscasts feature short-term weather forecasts, but long term forecasting has still eluded us. Some weather, such as rain, is essential to all life and rainmakers have been present in many cultures. There is no new water on our planet, it gets recycled in a process of evaporation and condensation which is outlined in the video, along with the various types of clouds, and the formation of thunder and lightning. Other fascinating facts are revealed: one bolt of lightning is a million volts strong and is five times hotter than the surface of the sun. When weather is pushed to the limits it can become a natural disaster, such as a tornado, hurricane or flood. We talk about it, study it, observe it and fear it, and over course of this thirty-minute video we will learn much more about it. After all, with eight to nine million lightning bolts hitting the planet every day, it is thought that the electrical activity of thunderstorms may have sparked the Earth to life.
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