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Antarctica: Land of Ice and Snow
Antarctica is the world's most southern continent. It covers about 5 million square miles. Of that five million miles, only about 100,000 miles is ice free. It's the fifth largest continent; and virtually uninhabitable for humans. The official human population is ZERO people, in all that five million miles of ice and snow.
There is life there, however:
- many kinds of algae
- mosses and other tundra vegetation.
The water also thrives with unexpected life. Weird water spiders; all kinds of beautiful and unexpected forms of unique life thrive in the pure,cold water of the Southern Ocean.
There are a few people in temporary residences who are research scientists, studying the last unpolluted environment on earth. With about 98% of the continent covered by ice at least one mile thick, there are NO indigenous peoples on this continent.
Antarctica is governed, if you want to call it that, by the Antarctica Treaty System. It was initiated in 1959; signed by 46 countries to date, and is the essential agreement prohibiting exploitation of Antarctica's natural resources and protection of its ecosystem. The treaty also prohibits military activities on this continent and promotes research.
Though Antarctica has the natural resources of coal and iron, and offshore oil, exploitation of these reserves ifs banned until 2048.
Antarctica is the worst place in the world for humans to live: it's the coldest, driest, windiest place, and very inimical to mankind. It has the highest average elevation of all the continents: Antarctica air is the purest, most rarefied air on earth.
Antarctica is also very beautiful, because it is so pure, so unspoiled. The scenery is so awesome. There are even cruise tours available for those hardy souls who want to seep themselves in this awesome beauty and are not bothered too much by the cold.
How cold is it? The coldest natural temperature ever recorded on Earth was about -90 degrees Celsius; -129 degrees Fahrenheit, on July 21, 1983, at the Russian Vostok Station in Antarctica. The warmest it ever gets is about 60 degrees Fahrenheit, or 15 degrees Celsius, near the coastline in the summertime.
The South Pole in Antarctica has black winters: the sun never shines. It has light summers: 24 hours of sunlight.
Antarctica contains about 70% of the world's fresh water, in the form of ice. Should all the ice on Antarctica melt, it would raise the sea level by about 200 feet.
Antarctic waters teeming with life
James Clark Ross sailed along a huge wall of ice in Antarctica that was later named the Ross Ice Shelf. It is one of the most awesome sights in the world.
Melting of floating ice shelves does NOT raise the sea level: that isn't the problem. Think of it this way: if you have a glass of water with ice in it, and the ice melts, it does not raise the level of liquid in the glass, because the ice displaces as much water volume as the melted ice in the form of water.
It is the outflow of glacial ice from land to form ice shelves on water that raises the sea level. And with the collapse of existing ice shelves, there is nothing to hold back the glacial ice from forming new ice shelves.
There is some concern that recent decades, seeing the collapse of previously stable large ice shelves, may increase the outflow of ice from landbound glaciers, thus raising the sea level significantly and contributing to global warming. A study showed a net loss of about 50 gigatonnes per year between 1992 and 2006: in subsequent years, this figure doubled, from the acceleration of outflow from glaciers in the Amundsen Sea Embayment.
It gets to a certain point, then the domino effect makes the results an exponential increase in both sea levels and release of potent greenhouse gasses, such as methane, from the melting ice; the global warming situation then becomes irreversible.
In 2002, the Antarctic Larsen-B ice shelf collapsed. In 2008, about 220 square miles of ice from the Wilkins Ice Shelf collapsed into the ocean, putting the remaining 5800 square miles of ice shelf at risk for imminent collapse. It held on by a thread until April, 2009, when the rest of the ice shelf collapsed into the ocean. In 2005, an area of ice roughly comparable to the State of California melted into the ocean. It did refreeze, fortunately, before migrating north into a more temperate zone.
Eroding Ice Shelf in Antarctica
NASA satellites recorded an 11.5 million mile hole in the ozone layer over Antarctica, in the year 2000. It has now shrunk to an 8.5 million mile hole, because of the ban of chlorofluorocarbons (CFC's). It may heal itself completely by the middle of this century.
But, in the meantime, the damage is done. This hole in the ozone layer over Antarctica has already caused some significant climate changes.
The ozone layer protects the Earth from ultraviolet radiation. The hole in the ozone layer exposed Antarctica and the surrounding ocean to extreme ultraviolet radiation from the sun, which increased polar wind speeds dramatically.
This had the effect of encapsulating the coldest temperatures to the South Pole; in the meantime, the coastal areas of Antarctica warmed. There was a dramatic increase in ice-shelf melt; it wasn't offset completely by snow to increase glacial formations. The net is a negative--a loss of ice from Antarctica.
This lack of shielding from ultraviolet radiation also showed in an increase in wind speed all throughout the southern hemispere and much greater storm intensity.