West Antarctica

79°S 100°W / 79°S 100°W / -79; -100

West Antarctica, or Lesser Antarctica, one of the two major regions of Antarctica, is the part of that continent that lies within the Western Hemisphere, and includes the Antarctic Peninsula. It is separated from East Antarctica by the Transantarctic Mountains and is covered by the West Antarctic Ice Sheet. It lies between the Ross Sea (partly covered by the Ross Ice Shelf), and the Weddell Sea (largely covered by the Filchner-Ronne Ice Shelf). It may be considered a giant peninsula, stretching from the South Pole towards the tip of South America.

West Antarctica is largely covered by the Antarctic ice sheet, but there have been signs that climate change is having some effect and that this ice sheet may have started to shrink slightly. Over the past 50 years, the west coast of the Antarctic Peninsula has been – and still is – one of the most rapidly warming parts of the planet,^[1][2] and the coasts of the Peninsula are the only parts of West Antarctica that become (in summer) ice-free. These constitute the Marielandia Antarctic tundra and have the warmest climate in Antarctica. The rocks are clad in mosses and lichens that can cope with the intense cold of winter and the short growing-season.