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

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

To understand the observations, the researchers ran computer simulations of heat transport in the upper atmosphere of a gas giant.

From Science Daily ● Jun. 11, 2026

Scientists interpret this as a genuine decrease in water because temperatures in the upper atmosphere are high enough to break water molecules apart into their constituent elements.

From Science Daily ● Jun. 11, 2026

We'd be skimming the upper atmosphere, so our orbit would rapidly decay.

From "The Martian" by Andy Weir