Glossary : Ultraviolet Radiation
The energy range just beyond the violet end of the visible spectrum.
Although ultraviolet radiation makes up only about 5 percent of all energy from the sun, it is the major energy source for the
stratosphere and mesosphere, playing an important role in both en
balance and chemical composition.
Most ultraviolet radiation is blocked by Earth's atmosphere, but some
solar ultraviolet makes it through and aids in plant photosynthesis and helps
produce vitamin D in humans. Too much ultraviolet radiation can burn the
skin, cause skin cancer and cataracts, and damage vegetation.
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