The Antarctic ( or , American English also or ; commonly ) is a polar region around Earth's South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau and other island territories located on the Antarctic Plate or south of the Antarctic Convergence. The Antarctic region includes the ice shelves, waters, and all the island territories in the Southern Ocean situated south of the Antarctic Convergence, a zone approximately wide varying in latitude seasonally. The region covers some 20 percent of the Southern Hemisphere, of which 5.5 percent (14 million km2) is the surface area of the Antarctica continent itself. All of the land and ice shelves south of 60°S latitude are administered under the Antarctic Treaty System. Biogeographically, the Antarctic realm is one of eight biogeographic realms of Earth's land surface. Geography As defined by the Antarctic Treaty System, the Antarctic region is everything south of the 60°S latitude. The Treaty area covers Antarctica and the archipelagos of the Balleny Islands, Peter I Island, Scott Island, the South Orkney Islands, and the South Shetland Islands. However, this area does not include the Antarctic Convergence, a transition zone where the cold waters of the Southern Ocean collide with the warmer waters of the north, forming a natural border to the region. Because the Convergence changes seasonally, the Convention for the Conservation of Antarctic Marine Living Resources approximates the Convergence line by joining specified points along parallels of latitude and meridians of longitude. The implementation of the convention is managed through an international commission headquartered in Hobart, Australia, by an efficient system of annual fishing quotas, licenses and international inspectors on the fishing vessels, as well as satellite surveillance The islands situated between 60°S latitude parallel to the south and the Antarctic Convergence to the north, and their respective exclusive economic zones fall under the national jurisdiction of the countries that possess them: South Georgia and the South Sandwich Islands (United Kingdom), Bouvet Island (Norway), and Heard and McDonald Islands (Australia). Kerguelen Islands (France; also an EU Overseas territory) are situated in the Antarctic Convergence area, while the Isla Grande de Tierra del Fuego, 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, and Gough Island and Tristan da Cunha group remain