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OZONE HOLE RESEARCH
May 1985 British scientists reported a steep drop, over several years,
of austral springtime ozone in the atmosphere above Halley Station, Antarctica.
The report seemed to confirm dire predictions made a decade before that
man-made chemicals (principally chlorofluorocarbons,or
CFCs) might destroy protective stratospheric ozone.
Discovering the causes
By November 1985 NSF delivered ozone
sensors, along with balloons and helium,to
researchers at McMurdo and Amundsen-Scott South Pole stations so they
could measure the loss of ozone as a function of altitude.
Then NSF, the National Oceanic and Atmospheric Administration (NOAA) and
the National Aeronautics and Space Administration (NASA) rapidly put together
a comprehensive research team to discover the depletions cause.
The team, arriving at McMurdo in late August 1986, established beyond
doubt that the chemistry of the stratosphere above McMurdo was grossly
abnormal and levels of key chlorine compounds were greatly elevated. In
just two months this group learned most of what we know about the ozone
The next year NSF, NASA, NOAA and international partners conducted an
all-out assault on the problem, returning to McMurdo and flying instrumented
airplanes from Punta Arenas, Chile.
The results strengthened and confirmed the previous years work.
While this campaign was still going on, international negotiators meeting
in Canada produced the "Montreal Protocol," which phased out
production of CFCs in industrialized countries.
This treaty was the first to address the Earth's environment, and it changed
forever a multibillion-dollar industry.The
ozone hole was the first definitive demonstration that humans are capable
of affecting the entire global system.