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![]() Perhaps the last true wilderness on Earth, Antarctica and the surrounding Southern Ocean contain some of the world's most productive and diverse polar ecoregions. The continent of Antarctica lies almost entirely within the Antarctic Circle although the Antarctic Peninsula extends northwards towards South America. It is covered by 90 per cent of the world's ice, with an average thickness of about 2,300 metres. Some 95 per cent of the land mass is covered by permanent ice or snow. Most of Antarctica is a cold desert with annual precipitation less than 50 millimetres and annual mean temperatures at the South Pole of -49ºC. The Peninsula, however, has much higher precipitation and average temperatures of -7ºC. The landmass and surrounding waters are critically important to global climate, and the entire region provides essential nutrients to the rest of the world's oceans, supporting life systems thousands of kilometres away from the Pole. Isolated from the rest of the world by the Southern Ocean, deep sea currents move the cold polar waters northwards, finally fanning out into the Atlantic, Indian and Pacific oceans. This water is replaced by southward converging water currents, which are warmer and more saline. Several zones of upwelling occur where these currents meet, providing high levels of nutrients which support luxuriant growth of tiny, microscopic marine organisms. These organisms in turn represent the foundation of one of the most productive ecosystems on Earth. One of these zones surrounds the Antarctic Peninsula and has particular impact on the Weddell Sea to the east of the Peninsula. The Antarctic environment is delicate: its soils are simple, its vegetation sparse and the small lakes of its few ice-free lowland areas recover slowly from human interference. But signs of former life have been recorded: fossil evidence of ferns, freshwater fishes, amphibians and reptiles have been recovered from Antarctica, bearing witness to the land's former connections with Australia, India, South America and other countries, prior to the break up of the supercontinent Gondwanaland, some 150 million years ago. Isolated from outside interference for millennia, many changes have occurred in the past few hundred years. Conservation and management of the entire Antarctic region is now an international concern and is covered by a variety of treaties, many of which have been influenced by WWF. The Antarctic Treaty, signed in 1959, was intended to facilitate scientific research and help ensure that all nations involved in research had equal access to the continent. Several other treaties and agreements have since been signed, including the Convention on Conservation of Antarctic Marine Living Resources, and the 1991 Protocol on Environmental Protection to the Antarctic Treaty, which succeeded in banning all mining for at least 55 years and generally strengthening Antarctic environmental controls. Ongoing scientific research plays an important role in the conservation and management of this wilderness area, providing a better understanding of the Antarctic ecosystem, and by furthering the development of conservation management policies to protect its terrestrial and marine habitats. |