Antarctica

Antarctica is the southernmost continent, surrounding the South Pole. It is surrounded by the Southern Ocean and lies largely within the Antarctic Circle. With about 14 million square kilometers (5.4 million square miles) of land, it is the fifth-largest continent by area and the only continent without a permanent resident population. Its main role is as a natural laboratory for climate, ice, and biology.

Geography and climate: Antarctica is the highest and driest continent, with a vast ice sheet averaging about 2,500 meters in thickness and covering almost all land. Interior temperatures can fall below -60°C in winter, while coastal areas may reach above freezing in summer. The continent receives very low precipitation, qualifying it as a polar desert.

Ecosystems: The terrestrial environment supports limited vegetation, mainly mosses, lichens, and algae. Surrounding seas are rich in life, including penguins, seals, and a food web centered on krill. Adaptations to extreme cold and seasonality are common among Antarctic organisms.

Human activity and governance: There are no permanent residents; researchers and support staff number about 1,000 in winter and up to around 4,000 in summer across numerous research stations. The Antarctic Treaty System governs the continent, restricting military activity, promoting scientific cooperation, and preserving environmental protections. Territorial claims exist but are held in abeyance under the treaty.

History: The continent was explored in the 19th and early 20th centuries, with expeditions by explorers from many countries. The name Antarctica derives from anti-Arctic, meaning opposite to the Arctic.