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

Far above the ground, the upper atmosphere has been cooling significantly for decades.

From Science Daily • May 14, 2026

This saw the capsule dip into the upper atmosphere, briefly climb again, then plunge back in so as to best cope with the heat, G-forces and splashdown accuracy needed.

From BBC • Mar. 31, 2026

As climate change shifts atmospheric conditions, experts warn that air travel could become bumpier: temperature changes and shifting wind patterns in the upper atmosphere are expected to increase the frequency and intensity of severe turbulence.

From BBC • Mar. 19, 2026

This region of the upper atmosphere is important because future astronauts will rely on it to transmit radio and navigation signals around the planet, much like communication systems on Earth.

From Science Daily • Mar. 14, 2026

As we began to penetrate the thin upper atmosphere, the sky out our windows began to change from the black of space to a tunnel of light.

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