The term Antarctic is used to refer to the southernmost region of the Earth - the area within the Antarctic Circle, which lies at 66 degrees, 33 minutes south latitude. This region includes the continent of Antarctica, the Southern Ocean, and the South Pole.
Characteristics of the Antarctic
The Antarctic region is cold. The mean winter temperature is -76 degrees Fahrenheit. Even in the summer, the mean temperature is a chilly -18 degrees Fahrenheit.
In addition to the extreme temperatures, the Antarctic also experiences extremes in daylight. In the Antarctic region the sun does not set on the December solstice and does not rise on the June solstice.
As mentioned above, the Antarctic region is home to the Southern Ocean - an ocean that was designated in 2000. This ocean was previously considered the southern portions of the Pacific, Atlantic and Indian Oceans. The southern ocean is the 4th largest of the Earth's 5 oceans (the Arctic Ocean is the smallest).
Antarctic Marine Life
Unlike the Arctic, the Antarctic has not been inhabited by humans since prehistoric times. In fact, the continent of Antarctica wasn't even discovered until 1821. Antarctica is visited by scientists and tourists, but there are no permanent residents, and the continent is not owned or governed by any single country.
Despite its low human population, the Antarctic is teeming with life, especially in the summer. During the winter, ice covers the continent and event the surrounding waters. But even at this dark time of year, the region isn't lifeless. Algae become trapped in the ice, and are food during the winter for krill, which seek shelter under the ice. As the region warms in the summer, the ice melts, algae are released and become a plankton "bloom," which provides more food for krill, which in turn experience a "bloom" of their own. This provides food for penguins, whales (such as orcas, minke, fin, humpback, sei, blue, sperm and southern right whales) and seals, many of whom migrate to Antarctic waters to feed during the summer.
Threats to the Antarctic
Threats to the Antarctic include climate change, whaling (i.e., Japan's controversial whaling of minke whales in the Southern Ocean), pollution and debris from old research facilities (that is currently being cleaned-up).
The opposite of Antarctic is Arctic, which refers to the northernmost region of the Earth, and the region around the North Pole. This is a more heavily-populated area, and the home of polar bears and walruses (but not penguins).