Antarctica (UK: or , US: (listen)) is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At 14,200,000 square kilometres (5,500,000 square miles), it is the fifth-largest continent and nearly twice the size of Australia. At 0.00008 people per square kilometre, it is by far the least densely populated continent. About 98% of Antarctica is covered by ice that averages 1.9 km (1.2 mi; 6,200 ft) in thickness, which extends to all but the northernmost reaches of the Antarctic Peninsula.
Antarctica, on average, is the coldest, driest, and windiest continent, and has the highest average elevation of all the continents. Most of Antarctica is a polar desert, with annual precipitation of 20 cm (7.9 in) along the coast and far less inland. The temperature in Antarctica has reached −89.2 °C (−128.6 °F) (or even −94.7 °C (−135.8 °F) as measured from space), though the average for the third quarter (the coldest part of the year) is −63 °C (−81 °F). Anywhere from 1,000 to 5,000 people reside throughout the year at research stations scattered across the continent. Organisms native to Antarctica include many types of algae, bacteria, fungi, plants, protista, and certain animals, such as mites, nematodes, penguins, seals and tardigrades. Vegetation, where it occurs, is tundra.
Antarctica is noted as the last region on Earth in recorded history to be discovered, unseen until 1820 when the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny sighted the Fimbul ice shelf. The continent, however, remained largely neglected for the rest of the 19th century because of its hostile environment, lack of easily accessible resources, and isolation. In 1895, the first confirmed landing was conducted by a team of Norwegians.
Antarctica is a de facto condominium, governed by parties to the Antarctic Treaty System that have consulting status. Twelve countries signed the Antarctic Treaty in 1959, and thirty-eight have signed it since then. The treaty prohibits military activities and mineral mining, prohibits nuclear explosions and nuclear waste disposal, supports scientific research, and protects the continent's ecozone. Ongoing experiments are conducted by more than 4,000 scientists from many nations.
The climate of Antarctica
is the coldest climate on Earth
. It is colder than that of the Arctic regions
because of the elevation, continental influence, and the fact that the Antarctic winter currently occurs when the Earth is just past its aphelion
. The Antarctic climate is also extremely dry, with an average of only 166 mm (6.55 in.) of precipitation per year; however, on most parts of the continent, the snow never melts and is eventually compressed to become the glacial
ice that makes up the Antarctic ice sheet
. The lowest natural temperature
recorded on the continent (and consequently on Earth) was −89.2°C (−128.6°F), recorded on Thursday, July 21, 1983, at Vostok Station
. The highest recorded natural temperature on the continent was 14.6°C (58.3°F) in two places, Hope Bay
and Vanda Station
, on January 5, 1974. The mean annual temperature of the continental interior is −57°C (−70°F), but the coast is warmer on average. In fact, McMurdo Station
on Ross Island
experiences a summer daytime average temperature of −3°C (26.6°F). The continent's unique location and its ice sheet
are of ongoing interest to science
that is engaged in climatology
and global warming
The entrance to the Cámara Base, located on Half Moon Island. The base is operational only in the summer, and is only accesable via the trail seen in the foreground.
Things to do
Did you know?
- ... that the lowest officially-recognized temperature ever recorded ,from a ground observer, in nature on Earth was an astounding −89.2°C (−128.6°F), recorded on July 21, 1983, at Vostok Station?. The lowest temperature ever recorded, from a space observer, was -93.2°C (-135.8°F), recorded on August 10, 2010, from the NASA Aqua satellite.
- ... that Antarctica is the only continent without reptiles or crawfish?
- ... that the first confirmed sighting of the continent was in 1820?
- ... that summer runs from October to February and winter takes over the rest of the year?
- ... that Antarctica is the driest continent?
- ... that ice can be 4 kilometers thick in some places?
- ... that there are no countries in Antarctica; the continent is instead governed by the Antarctic Treaty?