If you are seeking facts about Antarctica then you have come to the right place. This continent gets its name from the Greek word which means “opposite to the north,” which is very literal given its location directly across the globe from the North Pole (Arctic). The existence of Antarctica was only speculated by scientists and academics until 1820 when it was spotted during an exploration of the area. The infamous South Pole is found on the continent of Antarctica and was discovered in 1911.
Physical Geography
Physical geography involves the multidisciplinary development of information about the processes and patterns that exist and operate within the context of the natural environment. Fundamental information on antarctic physical geography has been collected by the CIA, among other sources.
You may supplement your understanding of physical geography by reading the following Encyclopedia of Earth articles:
Antarctica is the coldest, windiest, harshest continent, and with little precipitation (roughly two inches per year) is the driest place on earth. It is roughly 14 million sq km (5.4 million sq mi), has an average elevation of more than 2000 m (6500 ft), and 98% of the landmass is covered by an ice sheet estimated to be 29 million cu km (7 million cu mi).
The average annual temperature at South Pole Station is -56°F. During the austral summer, temperatures at McMurdo Station may reach as high as 50°F, while at South Pole Station the summer temperature may reach 0°F. Palmer Station has a milder climate, with summer temperatures reaching as high as 55°F.
Beneath its thick ice sheets, Antarctica is a dynamic and diverse continent with mountains, volcanoes, deserts, meteorites, dinosaur fossils, and some of the Earth’s most ancient crust.
The continent named Antarctica is also known as the South Pole, due to the fact that the geographical southernmost part of the planet is located within its borders. In many ways Antarctica is the most unique of the 7 continents, with special features not shared by any of the others.
Size
Antarctica is geographically unique in that it has no permanent borders or constant size. Although it is the fifth largest continent overall, its exact size in square miles varies according to the season. The change can be quite dramatic. In the summer, the continent is roughly half of the size of the United States. However, in the winter when the useable area expands due to snow and ice, the continent can more than double in size.
Climate
Being the coldest and windiest continent, Antarctica exhibits severe low temperatures that vary with latitude, elevation, and distance from the ocean. The average temperature is -49 °C. East Antarctica is colder than West Antarctica because of its higher elevation. The Antarctic Peninsula has the most moderateclimate. Higher antarctic temperatures occur in January along the coast and average slightly below freezing, but the strong temperature gradient between the ice-covered land and the sea, create constant strong winds that can blow up to 200 mph. The water temperature averages 33 °[[fahrenheit|F]. The continent is technically a desert, receiving less than 10" of precipitation annually.
Much research is being conducted on the climatology and meteorology of Antarctica because the conditions here are thought to have an enormous impact on climate patterns on the rest of the planet. There is also much interest in examining how both natural and anthropogenic changes in earth's climate are affecting the ice and biological processes. Because Antarctica contains 90% of earth's ice and 70% of its freshwater, any changes in temperature could cause the ice to melt and raise sea levels world-wide. At the present time, temperatures have risen about 5 degrees from their levels in 1974.
However, the continent was not always that cold. It separated from Gondwanaland about 30 million years ago and froze over about 14 million years ago.
The circumpolar ocean current, travels from west to east off the coast, effectively isolating the continent from the warmer ocean currents to the north. Upwelling of water provides not only nutrients that support a rich variety of ocean life, but provides a contact point for the ocean and the atmosphere to meet so thatcarbon dioxide can be absorbed.
Antarctica provides a wonderful laboratory to examine the historical patterns of earth's climate. Ice cores taken have enables scientists to peer back 740,000 years in time to analyze the chemistry of earth's atmosphere and to estimate the average temperatures.
The Ozone layer in earth's stratosphere seasonally thins (often referred to as the "ozone hole" as the spring sun warms the atmosphere over the south pole. Cause by the actions of Chlorine and Bromine, this destruction of ozone has profound implications for human health and the biological productivity of earth's ocean.
The White Continent
One thing Antarctica has in abundance is plenty of snow and ice. 98% of the continent is covered in ice, and about 70% of the world’s total supply of fresh water is frozen in Antarctica. No other continent is colder, drier or windier than Antarctica, which goes a long way towards explaining another unique feature, its low population.
No Citizens
So hostile is the environment of Antarctica that it has no permanent residents. Since no one lives there full time, there are no countries in Antarctica and no governments. That also means there is no form of Antarctic money in either dollars or coins. Yet, some people live and work in Antarctica on a part time basis. These are mostly summer visitors who tend to be almost exclusively scientists conducting various forms of research. There are over 60 scientific research stations operating in Antarctica, and the total combined population of the staff of these facilities can sometimes be as high as four or five thousand. A special international treaty allows anyone to use Antarctica for any peaceful purpose.
Wild Life
While Antarctica has no permanent human residents, it is home to a surprising variety of wild animals. Penguins and other birds such as the albatross can be found in Antarctica, as well as six types of seals and nine varieties of whales. Almost all the wildlife in Antarctica can be found near the shore, as the high winds and severe cold makes inland areas of the continent too inhospitable. There are over a thousand forms of fungi and lichen type plant life, but only two types of flowering plants on the whole continent. There are also 700 species of plankton.
If it were not so cold and covered in ice, Antarctica would be a desert much like the Sahara desert in northern Africa because it has little yearly precipitation. However, what little precipitation falls in the form of snow rarely melts, thereby creating deep and ancient snow drifts. Make no mistake about it, Antarctica is technically the largest desert in the world. With its extreme cold, it is unlikely that Antarctica will ever be densely populated or of much interest to humans except for scientific study. Yet, The White Continent of Antarctica remains interesting as a beautiful, large and in many ways unique place that is not quite like any other of the 7 continents.
Antarctica Wildlife
The cold, windy, and overall harsh climate of Antarctica keep wildlife to a minimum. However, there are a limited amount of insects and birds that call the continent home.
Antarctica is the only continent on earth that does not have an indigenous ant species.
There are several marine based animals that live in Antarctica such as seabirds, penguins, seals, squid, and whales. Most animals that survive in Antarctica share a common characteristic. They have thick layers of blubber (insulated fat) to keep warm. Some species have several inches of blubber to survive.
Land wildlife is very rare in Antarctica. The largest land based creature is actually an insect. The wingless midge is only a half an inch long (1.5cm).
Only one warm blooded animal remains year round in Antarctica. The emperor penguin stick around through the most unforgiving winter on Earth to care for their young without food!
Antarctica’s neighboring oceans are home to the most cold adapted animals on Earth. There are several species of fish that live in the waters near Antarctica that thrive in 0°C water.
Under such severe and harsh conditions there is hardly any vegetation in the Antarctic. Mosses and lichens cling to rocky areas. Black, white and green lichens have been found growing in tiny cracks in dry valleys.
Simpler organisms called algae grow on snow, in lakes and on the ice surrounding the continent. Some flower-bearing plants are found on the northern parts of Antarctica in warmer latitudes. Antarctica is devoid of greenery and any plant life. But in the surrounding sea, floating masses of vegetation that sustains thousands of marine birds and mammals are found.
Casey: the Daintree of Antarctica
Mosses emerging from a spring melt (Photo: Sharon Robinson)
Why is Casey special?
Antarctica is at the edge of life on the planet. Less than 0.5% of the Antarctic continent is ice-free rock or soil and therefore only tiny pockets of land are available for plants to establish. The Australian Antarctic Territory is home to some of the rarest ecosystems on the planet and the plant life at Caseyis as good as it gets – Casey has the most extensive and best developed plant communities in continental Antarctica: it is the ‘Daintree’ of Antarctica. The largest plants are the mosses and they are like miniature old growth forests, growing incredibly slowly. A single moss shoot may be over 100 years old. Very few plants can cope with Antarctic conditions which is why the Casey vegetation is so special.
Climate change has produced drying and warming in the east Antarctic region. The ozone hole has also elevated UVB radiation over the entire continent. Casey ecosystems can provide us with a valuable sentinel to measure the impact of climate change.
What plants are in the Casey region?
The plants at Casey can be divided into three groups:
1. Mosses and liverworts
During evolution mosses and liverworts were among the first plants to inhabit the land. Unique characteristics enable them to survive drying and freezing. Although mosses are really tough, they can only grow in the relatively wet areas around melt lakes and streams. Small moss patches also inhabit cracks in rocks and other sheltered areas where melt water is available. Melt of ice comes with the return of the sun in spring. Mosses and liverworts together form the group of plants called bryophytes. There are three species of moss in the Casey area –Schistidium antarctici (a species found only in Antarctica), Bryum pseudotriquetrum andCeratodon purpureus (species that are found across the world), and one liverwort, the thread-like Cephaloziella exililflora.
2. Lichens
Lichens can grow on most surfaces found in the Casey region (for example rocks, soil and also on mosses) and can absorb water from the air. Like mosses, lichens can survive long periods of desiccation. They can survive in very dry areas and are therefore widely distributed. Lichens are even found on exposed rocks within 500 km of the South Pole.
3. Terrestrial and snow algae
These plants belong to the same group as seaweeds. They are found in the nutrient rich areas around penguin colonies. Terrestrial algae thrive in the salty coastal areas where mosses and lichens cannot grow. Prasiola crispa (a species of terrestrial alga) grows as a green mat and looks like sea lettuce. Snow algae are similar to the algae that cause blooms in river and marine systems. They are colonies of microscopic algae, which reproduce rapidly in the snow when nutrient and temperature conditions are right.
What animals are in the Casey ecosystem?
The Casey region is home to colonies of Adélie penguins, snow petrels and Weddell and elephant seals. Most moss beds are the sites of abandoned ancient penguin colonies and these sediments provide nutrients for the plants to grow – a ready supply of ancient fertiliser. Although no large animals rely on moss for food, moss is home to many very small animals (invertebrates).
Studying the impact of climate change at Casey
A collaborative team of researchers from the Australian Antarctic Division, University of Wollongong, University of Tasmania, Australian National University and the University of Melbourne are currently studying the influence of climate change and human impacts on the Casey moss beds.
Minerals
Geologists have found coal, oil and natural gas in and around Antarctica. Deposits of gold, lead, zinc, manganese and copper have been discovered as well. However, exploration of minerals under the thick layer of ice in harsh weather conditions including strong winds, icebergs and rough seawaves is very difficult. Moreover the minerals occur in small amounts which makes their exploration uneconomical. ‘Conservationists’ feel that large-scale mining operations would harm Antarctica’s environment. Already they are faced with the problems of disposing off the wastes and scrap on the continent. The damages to the protective ozone layer around the Antarctic atmosphere is also a cause of great concern. What could be of use is the vast quantity of ice on the continent ? Can you think of a way that scientists could utilize the large icebergs of Antarctica some day.
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