You want to
talk about world records, Antarctica is the land of extremes. It is
the coldest, windiest,
and highest continent anywhere on earth. With
an average elevation about 7,544ft/2,300 meters above sea level it is
the highest continent. Even though it is covered in ice it receives
some of the least amount of rainfall, getting just slightly more rainfall
than the Sahara Desert, making it the largest desert on
earth. Most people have the misconception that a desert is a hot, dry,
sandy, lifeless place, but the true definition of a desert is any geographical
location that receives very, very little rainfall. Even though there's
ice on the ground in Antarctica, that ice has been there for a very
long time.
Antarctica is
the only continent that has never had an indigenous population of humans
because it has always been such an extreme environment. Just the boat
ride getting to the continent is over the most treacherous seas anywhere
in the world. The inaccessibility of the place and the lack of reliable
food and means for constructing shelter has kept humans away for thousands
of years. But the new technologies developed over the last 200 years
made it possible for people to reach these icy shores to explore and
study the Antarctic for the first time in human history.
Since there
are no people who claim Antarctica as their homeland, exploration of
the continent has been shared by all nations of the world. Scientists
from all over the world - Russia, Japan, the United States, United Kingdom,
Australia, New Zealand, South America, and many others - come to this
place in an internationally cooperative agreement to study the truly
unique qualities of Antarctica. Many scientific stations have been constructed
on Antarctica to provide shelter and supplies for scientists doing field
work there.
Meet
a scientist who's been to Antarctica - even went diving under the ice!
Some scientists
actually live on Antarctica for part of the year to conduct their research.
Very few scientists stay there more than six months at a time. The sun
rises and sets only once a year at the South Pole, which means there
are six months of daylight, followed by six months of darkness. During
the winter when there is no sun, the Antarctic becomes an even more
hostile place to be - colder than cold, BONE-CHILLING cold, and no daylight.
Can you imagine living in darkness 24 hours a day? That would almost
be like living out in space! Hey.....
The World's Biggest Laboratory
At first, the
scientific value of studying the Antarctic was just for the sake of
understanding this strange place. Recently, scientists have theorized
that the conditions in the Antarctic are similar to those on Mars. Because
of the similarities exploration of the Antarctic has taken on a new
meaning for the search for signs of life in the most extreme environments.
Antarctica is not only fascinating itself, but serves as an excellent
laboratory for studying the effects of space travel, developing new
technologies for exploring other planets and finding extraterrestrial
(yeah, alien) life.
Many, many fascinating
things have been discovered in the Antarctic that have challenged some
of our most basic ideas about what life on earth means. Some really
cool factoids:
Deepest
Earth Depression: The lowest point on earth is located
in the basin of the Bentley Subglacial Trench. At -2,555 meters (8,325
feet) below sea level it is the world's lowest elevation not under
seawater. It is not accessible because it is buried under the thickest
ice yet discovered.
90%
of the ice on earth is located in
Antarctica. There is so much ice there you could carve
up a block of ice the size of the Great Giza pyramid for every human
being on the planet! 98% of Antarctica is covered in ice.
Marine
Life: Some species of fish that live
in the waters around Antarctica are specially adapted to life in near-freezing
waters. Most living creatures on this planet have
hemoglobin
in their blood, which gives it that red color we all know so well.
These particular species of fish, however, have extremely low levels
of hemoglobin in their blood. So low that their blood isn't even red!
They also have natural antifreeze in their bodies to protect them
from freezing to death. (Even if you're a fish and the water in all
the cells of your body freezes and turns to ice crystals, you die.
'Nuff said). If you were to catch one of these fish and cut it open
the blood, gills and all the organs would be WHITE.
Weather:
Yes, the Antarctic has the coldest temperatures on the earth, but
that shouldn't surprise you. (Coldest reported temperature ever was
-89.4°C/-129°F.) What most people don't know is that the
South Pole has the clearest, calmest weather anywhere on earth. Most
of the wickedly high winds that everyone associates with the cold
and the ice of the Antarctic are around the edges of the continent
at the shores. These winds are so fast and so fierce they are world-famous
and they have a special name, too - katabatic
winds - and they can blow with hurricane force up to 304kmh/190
mph!
Believe it or
not with all the ice in the Antarctic, there is very little actual snowfall
or
precipitation. It does snow on the ice during the austral winter,
but measured on an annual basis the Antarctic is as dry as the Sahara
Desert.
Antarctic Ice
- The Ultimate Cool
Many scientists
study Antarctic ice because it is more than just ice. It has accumulated
over time, layer upon layer, building up over the millennia to create
a type of sedimentary rock. Yes, rock. Ice crystals can be considered
a type of mineral, and glacial ice is composed of crystals of the "mineral"
water. Just like sedimentary rock is created over time by the repeated
layering of particles of clay or sand, glacial ice builds up over millions
of years by the build up of snow that never melts.
Scientists drill
down deep into the ice with a drill that works kind of like a cookie
cutter, only it cuts out some really deep cookies of ice. These
core samples
contain many layers of ice that represent what the earth's atmosphere
was like at the time each layer of ice was formed. By studying the layers
of ice in the core samples scientists can learn about how the earth's
atmosphere has changed over geologic time.
In the winter
time the ocean around Antarctica freezes for thousands of miles in all
directions. This vast expanse of ice surrounding the already immense
Antarctic ice sheet covers over eleven million square kilometers.
The annual freezing of the ocean around Antarctica generates deep ocean
currents worldwide. Differences in ocean temperature are what cause
weather all over the globe. Some scientists fear that if the global
climate gets too warm or too cold it could affect the formation of Antarctic
ice, changing the climate as we know it all over the world.
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