Antarctic

The Antarctic is Earth’s polar region centered on the South Pole, inside the Antarctic Circle, and sits directly opposite the Arctic at the North Pole. It includes the continent of Antarctica, the Kerguelen Plateau, and various island territories that lie on the Antarctic Plate or south of the Antarctic Convergence. This region covers about 20 percent of the Southern Hemisphere, with the continent itself making up 5.5 percent of that area (14 million square kilometers). All land and ice shelves south of 60°S latitude fall under the Antarctic Treaty System.

Biogeographically, the Antarctic is one of eight major land-based realms on Earth. Climate change here is critical because melting the Antarctic ice sheet could significantly raise global sea levels. That melting also disrupts the Southern Ocean’s overturning circulation, which would alter local climate and marine ecosystems. No permanent country exists in Antarctica.

Under the Antarctic Treaty, the region is defined as everything south of 60°S. This treaty area covers Antarctica and the Balleny Islands, Peter I Island, Scott Island, the South Orkney Islands, and the South Shetland Islands. However, it does not include the Antarctic Convergence—a shifting zone about 32 to 48 kilometers wide where cold Southern Ocean waters meet warmer northern waters, forming a natural boundary. Because the Convergence moves with the seasons, the Convention for the Conservation of Antarctic Marine Living Resources approximates it by connecting specific points along latitude and longitude lines. An international commission based in Hobart, Australia, manages this convention through annual fishing quotas, licenses, onboard inspectors, and satellite surveillance.

Islands between 60°S and the Antarctic Convergence, along with their 200-nautical-mile exclusive economic zones, belong to the countries that claim them: South Georgia and the South Sandwich Islands (UK), Bouvet Island (Norway), and Heard and McDonald Islands (Australia). The Kerguelen Islands (France, also an EU overseas territory) sit within the Convergence area. Meanwhile, Isla Grande de Tierra del Fuego, the Falkland Islands, Isla de los Estados, Hornos Island with Cape Horn, Diego Ramírez Islands, Campbell Island, Macquarie Island, Amsterdam and Saint Paul Islands, Crozet Islands, Prince Edward Islands, Gough Island, and the Tristan da Cunha group all lie north of the Convergence and outside the Antarctic region.

Antarctica

On the continent, less than 1 percent of land is ice-free. Animals that live there at least part of the year include seals, penguins, South Georgia pipits, albatrosses, Antarctic petrels, whales, fish like Antarctic icefish and Antarctic toothfish, squid such as the colossal squid, and Antarctic krill. Only two flowering plants grow there—Antarctic hair grass and Antarctic pearlwort—along with mosses, liverworts, lichens, and macrofungi.

Sub-Antarctic Islands

On sub-Antarctic islands, biodiversity among land plants and animals is low. Studies suggest the harsh climate limits species richness, but correlations also exist with island area, temperature, remoteness, and food chain stability. For instance, few herbivorous insects survive because plant diversity is low, and native bird numbers depend on those insects as a major food source. Examples of such islands include Isla de los Estados (Argentina) and Isla Grande de Tierra del Fuego (Chile).

Conservation

The Antarctic contains the world’s largest protected area: the South Georgia and South Sandwich Islands Marine Protection Area, created in 2012 and covering 1.07 million square kilometers. That surpasses Greenland National Park’s 972,000 square kilometers. (The Ross Sea Marine Protection Area, established in 2016, is even larger at 1.55 million square kilometers, but its protections expire in 35 years.) To safeguard the region, all Antarctic ships over 500 tonnes must follow the Polar Code, adopted by the International Maritime Organization and in force since 1 January 2017.

People

The first recorded sighting of Antarctica is credited to Spaniard Gabriel de Castilla, who reported seeing distant snow-capped mountains in 1603. The first land discovered was South Georgia, visited by English merchant Anthony de la Roché in 1675.

Although myths of a Terra Australis date back to antiquity, the first confirmed sighting of the continent itself is widely accepted as 1820, by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on the ships Vostok and Mirny. The first human born in the Antarctic was Australian James Kerguelen Robinson, on 11 March 1859, aboard the sealing ship Offley in the Gulf of Morbihan, Kerguelen Island. The first human born and raised on an Antarctic island was Solveig Gunbjørg Jacobsen, born on 8 October 1913 in Grytviken, South Georgia.