upper atmosphere

American  

noun

Meteorology.

1. the portion of the atmosphere above the troposphere.

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upper atmosphere British  

noun

1. meteorol that part of the atmosphere above the troposphere

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upper atmosphere Scientific  

1. 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.

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Etymology

Origin of upper atmosphere

First recorded in 1890–95

Example Sentences

See Examples For:

upper atmosphere

Ballistic missiles travel into the upper atmosphere or space before plunging back down toward a target, but not all are capable of maneuvering.

From The Wall Street Journal ● Jul. 25, 2026

Cherubim and his colleagues developed a theoretical model predicting that the upper atmosphere of LHS 1140 b would contain large amounts of helium slowly escaping into space.

From Science Daily ● Jul. 21, 2026

But the only gas discovered in the atmosphere so far is helium, probably in the upper atmosphere, which on its own would not support life.

From BBC ● Jul. 17, 2026

Typically, winds in the upper atmosphere can weaken or disperse gravity waves before they reach such heights.

From Science Daily ● Jun. 3, 2026

As we entered the upper atmosphere, there was a five-minute period in which we were “blacked out”; that is, we couldn’t talk on the radio.

From "Flying to the Moon: An Astronaut's Story" by Michael Collins