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upper atmosphere

noun, Meteorology
the portion of the atmosphere above the troposphere.
Compare upper air.
Origin of upper atmosphere
1890-95 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for upper atmosphere
  • The charged particles are accelerated to high energies and stream into the upper atmosphere.
  • The deep ocean, of course, is every bit as unexplored and little understood as the upper atmosphere.
  • As he travelled, he set up instruments called magnetometers to measure electric currents in the upper atmosphere.
  • Some, however, are the result of collisions between cosmic rays and the gases of the upper atmosphere.
  • We can even live under water or in the upper atmosphere for a while, with suitable technology.
  • The agency's aim is to collect data on the distribution in the upper atmosphere of climate-affecting gases.
  • It involves pumping sulphur dioxide into the upper atmosphere.
  • In a future hydrogen economy, more hydrogen will escape into the upper atmosphere.
  • Some climate scientists want to put materials into the upper atmosphere to block out the sun.
  • The ionosphere is a region of the upper atmosphere that contains atoms ionized by radiation from the sun.
British Dictionary definitions for upper atmosphere

upper atmosphere

(meteorol) that part of the atmosphere above the troposphere
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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upper atmosphere in Science
upper atmosphere  
The part of the atmosphere above the troposphere. The upper atmosphere includes the mesosphere, the ionosphere, the thermosphere, and the exosphere. Temperatures in the upper atmosphere decrease with increasing altitude except in the thermosphere, where temperatures increase significantly with altitude, because the few molecules present receive intense solar radiation.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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