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5. Conclusions
Ultraviolet radiation is a small but significant portion of the
Sun’s output. Its effects on humans is neutral or beneficial in
small doses (Vitamin D formation), but exposure to higher levels
may produce a painful or even life-threatening sunburn. Chronic
exposure to ultraviolet radiation is associated with increased
aging of the skin as well as skin cancers and cataracts.
Stratospheric ozone protects us and many living things from high
levels of ultraviolet radiation. Unfortunately,
chlorofluorocarbons and similar compounds destroy stratospheric
ozone as demonstrated by the development of a dramatic seasonal
ozone hole over Antarctica. Fortunately, this was recognized in
a reasonably timely fashion, and these compounds are no longer
being manufactured or used to anywhere near their previous
levels; hopefully, they will not contribute further damage to
the ozone layer.
Where this will all end in the next 50 to 100 years and what
more we should be doing about it are interesting and important
questions far beyond the scope of this essay. Let us hope they
are properly answered in enough time for us to mitigate and
reverse any unintentional damage we have ignorantly done to our
protective atmosphere.
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