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Antarctica:
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Unequaled Extremes | Looking
for Life | Life in the Icebox | Of
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UNEQUALED
EXTREMES
On a planet of extremes, Antarctica has no equals. Indeed, it is a
triple-crown winner, simultaneously holding the records for planet Earth's
coldest, driest, and windiest place.
As NATURE's ANTARCTICA: THE END OF THE EARTH starkly illustrates, the
continent at the bottom of the world is covered by an immense ice sheet.
Over 95% of the continent is covered by layers of ice, immense bulks
sometimes almost three miles thick. An estimated 70% of the planet's
fresh water is locked up in those frozen crystals.
Despite all the water, however, Antarctica is technically a desert.
Less than two inches of precipitation fall a year, about the same as
in Africa's arid Sahara. And in Antarctica's Dry Valleys -- the continent's
largest ice-free region -- measurable precipitation is believed to have
been absent for two million years.
But while most deserts are hot, Antarctica is anything but. In fact,
the lowest temperature ever recorded on this planet was -129 degrees
Fahrenheit, documented in 1983 at the Russian Antarctic research base
in Vostok. One reason for the frigid climate is the Antarctic's legendary
Katabatic winds, masses of air that literally fall off the continent's
high inland plateau toward the sea at speeds of up to 200 miles per
hour. ("Katabasis" is Greek for "descent.") In some places, the wind
scours every crystal of snow and grain of sand from the surface, sculpting
rocks and ice into weird shapes and haunting towers.
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Not surprisingly, the combination of wind and cold makes Antarctica one
of the most inhospitable places on Earth. But as ANTARCTICA: THE END OF THE EARTH
shows, the creatures that live in this area, from penguins to seals to seabirds,
have figured out remarkable ways to survive. And even people have found methods
to establish small underground towns where they can stay warm enough to conduct
scientific studies, even in the dead of the polar winter.
But even these high-tech communities are at the whim of the weather, which
cuts them off from the rest of the world for months at a time. In 1999,
the world learned of a tense medical drama: one of the researchers stationed
in Antarctica, Dr. Jerri Nielsen, an American physician at the Amundsen-Scott
South Pole Station, discovered that she was suffering from cancer -- after
the last flight of the year had already taken off. She was left stranded,
without the medical supplies she desperately needed. In the frigid month
of August, cargo pilots had to make several dangerous flights to drop
the supplies to the surface, and the ill researcher was able to give herself
chemotherapy while waiting for rescue. But fierce winds and snowy white-outs
forced the pilots to abandon several efforts to evacuate her, until they
were finally able to airlift her out in October of 1999.
During such missions, the pilots get just "a half-hour on the ground --
if that," before engines and fuel lines begin to freeze, notes Arthur
Brown, a spokesman for the National Science Foundation, which runs the
polar base. Given such conditions, delays are "pretty much the drill until
the weather says 'Yep, it's OK you can go,'" adds another official.
Antarctica: The
End of the Earth Home
Unequaled Extremes | Looking
for Life | Life in the Icebox | Of
Time Machines and Icebergs | Resources
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