Antarctica receives a very low amount of precipitation, being one of the driest areas of the world (in terms of rainfall levels). About 50 mm of rainfall are expected here annually. This value rises as we approach the shore, reaching in the coastal areas almost 200 mm / year.
The precipitations are composed largely of snowfall brought by cyclones. Usually they fall as snow or ice, and sometimes rainfalls are also recorded in the coastal areas. There are several types of climate in Antarctica; although all are cold, they differ on severity. Like the rainfall, the climate tames as the latitude decreases. The Antarctic Peninsula is the area where we can meet the mild climate, and the temperature here can reach 0 C during the warmer season.
Almost entirely covered by a thick layer of ice, Antarctica has very little land available for the formation of soil and the vegetation appearance. The existing soil was formed during the most recent period of the continents existence and it has a low organic content, as well as a low water storage capacity.
Antarctica is isolated from other continents so it is very difficult for any type of vegetation to spread on its territory. The low constant temperature, the lack of humidity and the strong winds discourage the growth of plants. Exceptions are the plants that can adapt to these conditions, being able to actively develop only a few days a year. The climatic factors limit the existence of plants in Antarctica to the kingdom Protista (simple organisms, usually unicellular) algae, lichens and moss. The lichens found throughout Antarctica have an incredibly slow rate of growth. Only two known species of plants that flourish are in Antarctica, they are found in the Antarctic Peninsula and in the islands around it.
The continent has no equivalent of the Arctic tundra, where there is a greater variety of plants: the richest vegetation in Antarctica can be compared more with the one from north, the poor vegetation of the arctic polar deserts. However, patches of vegetation grow on the rocks which are not ice-covered, up to 290 km from the South Pole. Snow algae grow on snow and on ice surfaces near the coast, particularly along the Antarctic Peninsula, where the sea birds and the ocean breezes provide opportunities for nutrition.