Antarctica is the world’s southernmost continent, and is completely surrounded by the Southern Ocean. It is the fifth largest continent in the world, with an area of 14 million km². The continent of Antarctica is a rocky landmass of islands, but most of this landmass is covered by a thick layer of ice called the Antarctic Ice Sheet. Because of the thickness of the ice sheet, Antarctica has the highest average elevation of any continent.
Antarctica is a land of extremes, as it is the coldest, driest, windiest continent on Earth. Air temperatures vary greatly over the continent, with an average annual air temperature of -57 °C in the interior of Antarctica, compared to an average annual temperature of -20 °C at Scott Base in the McMurdo Sound region. The coldest temperature ever recorded on Earth was in Antarctica at the Russian Base Lake Vostok in 1983, where the temperature reached -89.2 °C!
The average precipitation also varies greatly over Antarctica. Though some coastal regions of Antarctica experience more than 1000 mm of precipitation a year, the interior of Antarctica is considered a desert as it receives very little precipitation. On average, the continent of Antarctic receives 166 mm of water equivalent precipitation each year. Wind speed, direction, and temperature vary greatly in different areas of Antarctica, and are mostly controlled by air pressure, the rotation of the earth, and the ice and snow on the land.
Among the most notable winds in Antarctica are the katabatic winds that flow down off of the Antarctic Ice Sheet and reach very high speeds. Antarctic winds have been recorded at up to 320 km/hour. Another interesting feature of Antarctica is the cycles of light and dark over the year. Antarctica experiences periods of 24 hour daylight in mid-summer and 24 hour darkness in mid-winter. At Scott Base, the sun sets in late April and does not rise again until the end of August. At the South Pole, the sun sets in late March and does not rise again until mid September.
The Antarctic Dry Valleys are located to the west of McMurdo Sound in the Ross Sea Region. Covering approximately 5000 km², the Dry Valleys make up the largest ice-free area in Antarctica.
Life is incredibly resilient. We may be tempted to think that an environment as desolate and hostile as the Dry Valleys, being completely incompatible with human existence (without Antarctic gear, anyway),
Although the geology of Antarctica goes back over three thousand million years, the oldest rocks found in the Dry Valleys are (only!) about 650 million years old.
Huts were built for expeditions from 1899 and some still stand making Antarctica the only continent where original human habitation structures remain. Of the 22 original sites, only seven huts remain intact today.
The study of high temperature extreme environments challenges our understanding of the upper tolerances of microbial life and may provide a window to understanding how life originated on earth.
In October 2012 Prof. Craig Cary was gone for just over a week to join a 4 person team which visited 2 other geothermal sites in Antarctica to survey and review the protection of these unique sites.
The Ross Dependency is New Zealand’s wedge shaped territorial claim of an area of Antarctica including the Ross Sea, Ross Ice Shelf, Ross Island, and the Transantarctic Mountains, extending to the South Pole.
Scott Base, New Zealand’s Antarctic base, is located at Pram Point on Ross Island in McMurdo Sound. It was originally built in 1957, and rebuilt to be a suitable permanent base from 1976 to 1977