If Antarctica's ice sheets melted, the world's oceans would rise by 60 meters. Currently 200 times all of the fresh water stored in the worlds lakes, rivers and is frozen in Antarctic ice sheets, and it would take 1000 years for the water discharged from these lakes and rivers to fill the ice cap to its current volume.The Antarctic ice cap has 7 million cubic miles of ice. This is 90% of all the ice on the planet and 70% of all of the world's fresh water. Only about 2% percent of Antarctica is not covered by ice.
The weight of the ice sheets covering Antarcitca physically lowers the continent. If all of the ice were to melt, then the continent would slowly raise back up until it reaches and equilibrium.
This process is known as isostatic rebound.
Scotland and Scandinavia are still rebounding today after the last ice age - at the rate of half a meter a century in the Northern Baltic - the fastest place.
The ice averages one and a half miles in thickness, with the thickest ice being almost three miles thick.
The Lambert Glacier in East Antarctica, the world's largest valley glacier, discharges some 8.4 cubic miles of ice into the Avery Ice Sheet every year.
At depths of 10,000 feet, the weight of the ice is some 30 tons per square foot.
The polar ice cap around the South Pole advances about 33 feet annually.
Antarctica's area is 5.4 million square miles. That's 1.5 times the entire area of the USA!
The largest iceberg ever spotted was sighted by the USS Glacier on November 12, 1956. It measured
208 miles long by 60 miles wide--the size of Belgium.
Samples of ice known as ice cores are regularly drilled in Antarctica by scientists. They are removed as a long cylinder of ice that records snow fall as far back as 30 thousand years! The properties of the ice, the dust trapped within it, and even the air bubbles in the ice give valuable information about the earth's climate at various times in the past.
Antarctica is the highest, driest, coldest, and windiest continent.
Most of Antarctica is a desert, with the annual snow accumulation over much of East Antarctica being the equivalent of less than two inches of rainfall.
The Transantarctic Mountain range, which separates East and West Antarctica, is one of the world's great mountain ranges, stretching a full 3,000 miles--the width of the continental U.S.Mount Vinson, Antarctica's highest mountain at 16,600 feet, was discovered only in 1958 by U.S. Navy Aircraft.
The lowest point on the continent is the Bentley Subglacial Trench, which is 8,325 feet below sea level.
From November to February the sun does not set, but rather circles overhead. Starting in February the sun dips down below the horizon for just few minutes a day. Through March this period of darkness increases as daylight shortens. Finally in April the sun never rises and it remains sunless until September when the sun begins to rise for longer periods of time each day. By November the sun never sets and the annual cycle repeats. Check out this animation.
The mean summer temperature on the East Antarctic Ice Sheet is -22°F and mean winter temperature around -76°F. The lowest temperature ever recorded was at the Russian Vostok station, -129°F
Antarctica is the best place in the world to find meteorites. Dark meteorites show up against the white expanse of ice and snow where they remain unweathered and exposed due to the lack of vegetation. In places the ice flows into natural barriers where it slowly melts to expose the meteorites that were hidden within the ice. These areas are known as "cul-de-sacs" becuase of their high concentration of meteorites.
The cold and dry conditions in the Dry Valleys region of Antarctica are so close to those on Mars that NASA did testing there for the Viking mission.
The cold ocean surrounding Antarctica has circulated for the past 20 million years and is distinct from the waters to the north due to its temperature, speed and salinity. This division, known as the Antarctic Convergence, prevents fish and other marine life from mixing with their neighbors to the north, which has allowed them to adapt very well to extremely cold temperatures.
Antarctic fish have lived at between 36°F and 28°F for 5 million years (28°F is the freezing point of sea water, which is lower than fresh water because of the salt). They are therefore the best cold adapted animals known on earth, and even have antifreeze molecules, known as glycopeptides in their blood.
Antarctica has a unique group of fish called Ice Fish. These fish have no haemoglobin in their blood to carry oxygen. The extremely cold water can dissolve more oxygen than warm water, so they get by perfectly well without haemoglobin. They have a larger volume of clear blood instead and so unusually have a ghostly white color, particularly their gills. Researchers have found that ice fish DNA has been damaged by high levels of ultraviolet light resulting from the ozone hole.
It has been estimated that during the feeding season in Antarctica, a full grown blue whale eats about 4 million krill, small shrimp-like animals, per day that's 4 tons every day for 6 months. The daily intake would feed a human for about 4 years!
Antarctica's largest land animal is a wingless midge (Belgica antarctica), which grows to half an inch long. The largest land predator is a mite that weighs only 100 micrograms.
Antarctica has just two native flowering plants, Deschampsia antarctica (a grass) and Colobenthos subulatus (a pearlwort).
Of some 20,000 fish species, only about 120 swim in Antarctic waters.
Antarctica is pushed into the earth by the weight of its ice sheets. If they melted, it would "spring back" about 500m (1 625 ft). It would do this very slowly taking about 10000 years to do so.
Scotland and Scandinavia are still rebounding today after the last ice age - at the rate of half a meter a century in the Northern Baltic - the fastest place.
Antarctica is the best place in the world to find meteorites. Dark meteorites show up against the white expanse of ice and snow and don't get covered by vegetation. In some places, the way the ice flows concentrates meteorites there.
The cold and dry conditions in the "Dry Valleys" region of Antarctica are so close to those on Mars that NASA did testing there for the Viking mission. It has not rained in the dry valleys for at least 2 million years.
One of the biggest icebergs ever (possibly the biggest iceberg ever) broke free from the Ross ice shelf in Antarctica in 2000.
It was 295km (183 miles) long and 37km (23 miles) wide, with a surface area of 11,000 sq km (4,250 square miles) - similar in size to The Gambia, Qatar, The Bahamas, or Connecticut - above water - and 10 times bigger below.
It has been estimated that during the feeding season in Antarctica, a full grown blue whale eats about 4 million krill per day (krill are small shrimp-like creatures), that's 3600 kg or 4 tons - every day for 6 months.
The daily intake would feed a human for about 4 years! (if you could stomach it, krill may be nutritious but they're not very nice as people food - fortunately for the whales!).
Since the Antarctic convergence arose about 20 million years ago, there has been very little exchange of fish or other marine life in either direction.Antarctic fish have lived at between +2C and -2C for 5 million years (-2C is the freezing point of sea water, below zero because of the salt). They are therefore the best cold adapted animals that there are on the planet - now or ever.
A domestic deep freeze runs at about -20?C. The mean summer temperature on the great East Antarctica icecap is -30?C and mean winter temperature around -60?C.
The lowest ever temperature recorded was at the Russian Vostok station, - 89.6?C
When the Antarctic sea-ice begins to expand at the beginning of winter, it advances by around 40000 square miles (100000 square kilometres) per day, and eventually doubles the size of Antarctica, adding up to an extra 20 million square kilometres of ice around the land mass.
That's one and a half USA's, two Australia's or 50 UK's worth of ice area that forms, then breaks up and melts on an annual basis.
Snow falling at the South Pole takes about 100 000 years to "flow" to the coast of Antarctica before it drops off the end as part of an iceberg.
11/ The Antarctic ice cap has 29 million cubic kilometres of ice. This is 90% of all the ice on the planet and between 60 and 70 % of all of the world's fresh water.
Only about 0.4 percent of Antarctica is not covered by ice.
Antarctica has a peculiar group of fish called the ice fish. These have no red pigment - haemoglobin - in their blood to carry oxygen around. Because the temperature is so low and oxygen dissolves better in cold temperatures, they get by perfectly well without it. They just have a larger volume of clear blood instead and so unusually have a ghostly white colour, particularly their gills.
These ice fish have recently been shown to have their DNA damaged by high levels of ultra violet light resulting from the ozone hole (they have less pigment to prevent the UV getting through).
Many other Antarctic sea creatures including fish have antifreeze in their blood so they don't accidentally get frozen solid!
The largest land animal in Antarctica is an insect, a wingless midge, Belgica antarctica, less than 1.3cm (0.5in) long. There are no flying insects (they'd get blown away), just shiny black springtails that hop like fleas and tend to live among penguin colonies.
Samples of ice known as ice cores are regularly drilled through the ice in Antarctica by scientists. They are removed as a long cylinder of ice that gives an indication of the past going back tens of thousands of years. The properties of the ice, of dust trapped in the ice, and even of air bubbles trapped in the ice give valuable information about the earth's climate at various times in the past.
In 1981 a swarm of krill was tracked by US scientists that was estimated at being up to 10 million tonnes of krill!!!!! This is the equivalent of about 143 million people (at an average of 70kg each) or more than the entire populations of the UK and Germany combined ( and wandering around in a group!)
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