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Glossary

U

ultraviolet

Electromagnetic radiation resembling visible light, but of shorter wavelength. The eye cannot see UV, and much of it is absorbed by ozone, a variant of oxygen, at altitudes of 30-40 km


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ultraviolet radiation

The energy range just beyond the violet end of the visible spectrum. Although ultraviolet radiation constitutes only about 5 percent of the total energy emitted from the sun, it is the major energy source for the stratosphere and mesosphere, playing a dominant role in both energy balance and chemical composition.


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USAF

United States Air Force

USGS

United States Geological Survey