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In 1977, scientists
first detected that there was a hole in the ozone layer over Antarctica.
However, it was not until 1985 that British meteorologists confirmed it
with indisputable evidence. The ozone layer - the atmospheric layer which
blocks out 99 percent of the sun's ultraviolet rays, had developed a gaping
hole high over the North Pole.
Satellite data showed
that the Antarctic's ozone grew thinnest every October, with 40 percent
of the layer vanishing. Evidence also showed that 2.5 percent of the planet's
ozone had disappeared altogether. The implications were terrifying - ultraviolet
radiation can cause skin cancer, kill phytoplankton (the base of the
ocean food chain), damage crops, blind animals and cause other as yet
unforeseen disasters.
Scientists pointed
to man-made air pollutants called chlorofluorocarbons (CFCs) as
the cause. Scientists have calculated that every atom of CFC which rises
into the stratosphere could destroy 100,000 ozone molecules. In 1978,
the US government banned the use of CFCin aerosol spray cans, but manufacturers
continue to use CFCs in refrigerators, air-conditioners, industrial solvents
and plastic foams. And other countries still used them in spray cans.
On top of that, CFCs
were discovered to be a main cause of the newly discovered "greenhouse
effect", which causes solar heat to be trapped near the ground by airborne
pollutants. Scientists predict that within 50 years the earth's average
temperatures could soar to eight degrees as 1980 levels. There
are global fears that global warming will melt the ice caps and flood
coastal cities. The accompanying climactic change would also turn presently
fertile regions into deserts. In 1987, 53 countries signed the Montreal
Protocols, agreeing to eliminate CFC use by the year 2000. Production
elsewhere continues unstopped however, and the CFCs used years earlier
still remain in the atmosphere.
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