Glossary : Ultraviolet Radiation
The energy range just beyond the violet end of visible light.
Although ultraviolet radiation constitutes only a small portion of the
total energy emitted from the sun, it is the major energy source for the
stratosphere and mesosphere, playing an important role in both energy
balance and chemical composition.
Most ultraviolet radiation is blocked by Earth's atmosphere, but some
solar ultraviolet gets through and helps plants to make foods and people to make vitamin D. Too much ultraviolet radiation can burn the
skin, cause skin cancer and eye problems, and hurt vegetation.
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