Antarctica is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole, first reached in 1911 by Norwegian explorers. Antarctica is, on average, the coldest, driest, and windiest of the continents. It is mainly a polar desert, though 70% of the world's freshwater reserves are frozen there, which, if melted, would raise global sea levels by almost 60 m (200 ft). Native animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation occurs, it is mostly in the form of lichen or moss. Some countries have territorial claims in Antarctica, but by treaty, the continent is set aside as a scientific preserve. During the summer months, about 5,000 people reside at research stations there, a figure that drops to around 1,000 in the winter. Despite Antarctica's remoteness, human activity significantly impacts it via pollution, ozone depletion, and climate change. (Full article...)