Abiotic factors are the non-living parts of an ecosystem. The abiotic factors of Antarctica are its low temperatures, small amount of precipitation and polar ice sheet. Abiotic factors work with the biotic, or living, factors to shape the ecosystem.
Antarctica is a polar desert. It receives less than 50 millimeters of precipitation per year, and the relative humidity drops to as low as 0.03 percent. Antarctica maintains its ice cover in these conditions because very little of the snow and ice melts or sublimates. Instead it continues to accumulate over time, forming the thick ice sheet.
In addition to its ocean and ice sheet habitats, Antarctica has a thriving ecosystem of underwater lakes. These lakes are protected from the cold by the ice sheet and have not been exposed to sunlight or open air for at least 120,000 years. Some scientific estimates place their formation as far back as one million years. These lakes form the world's largest unexplored ecosystem, covering 9 percent of Earth's landmass.
Archaea and bacteria are confirmed to live in these lakes, and conditions are hypothesized to support protists. The possibility exists that small worms and arthropods can survive in this ecosystem, but the food supply available in the lakes would not sustain larger organisms.