Saturday, February 21, 2009

ANTARCTICA

Coldest Place.... 
ANTARCTICA

A Really "Cool" Place to Be a Scientist

You want to talk about world records, Antarctica is the land of extremes. It is the coldestwindiest, andhighest 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 avery 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.

Antarctic Snowscape, Antarctica

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 hemoglobinin 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 somereally 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.

Antarctica Landscape, Antarctica 

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