In our article, we want to talk about Antarctica - a distant lost mainland, located in the very south of the Earth. Let's figure out what this mysterious continent is. What oceans wash Antarctica? And what is the mainland climate?
What waters is Antarctica washed by?
Starting a conversation about the mainland, you need to figure out which oceans wash Antarctica, since it is their currents that determine the climatic conditions in which it is located.
I would like to emphasize that the center of the continent approximately coincides with the South Pole (geographical). The shores of Antarctica are washed by three oceans: the Pacific, Indian and Atlantic. Unofficially, they are united in the Southern Ocean. Naturally, in geography you will not meet such a concept.
Antarctica includes the mainland itself and the islands adjacent to it, while its area is more than fourteen million square kilometers.
South ocean
When wondering which oceans wash Antarctica, it should be understood that it is not without reason that they are combined into a single whole (Fifth Ocean). They really surrounded the continent in a continuous ring.
Division of the oceans is a rather complex process that has been studied for decades before it became possible to talk about four components (Pacific, Indian, Atlantic and Arctic). Of course, the borders of such huge water masses cannot be drawn by a single unchanging line. Nevertheless, they are determined by the unity of those processes that occur in this area of the hydrosphere. An important role in this is played by the shape of the coastline, the relief of the shelf, and many other factors.
Studying which oceans wash Antarctica, scientists came to the unspoken decision to combine them into a single one - the South. The fifth (southern) ocean is huge. A detailed study of it took a long time, because it is not so easy to understand the mode of its existence.
The bottom relief of the Southern Ocean is very complex and peculiar. The main feature is that incredible depths are observed near the mainland. The width of the shelf is one hundred and fifty kilometers. After such a shallow, a sharp drop in depths is observed.
In general terms, the ocean floor around the mainland consists of three huge depressions with significant depths. They are united in a single ring around Antarctica. The depth was considered the greatest at 8252 meters, but later a depth of 8590 meters was discovered by echo sounders, which was called the Byrd Basin.
Climate of Antarctica
Antarctica is the most severe continent on the whole Earth. On its territory, air temperature is never above zero. But it was not always so. In the Mesozoic period, the climate on the entire planet was more humid and warmer. And Antarctica in those days was much closer to the equator; tropical forests grew on it. But millions of years have passed since then, and the mainland found itself in the circumpolar zone, which led to the glaciation of the entire continent. This event not only changed the climate of Antarctica, but also caused a cooling in the entire southern hemisphere. In addition, the tropical ocean called Tethys disappeared, which warmed it with its warm waters. And around the Arctic a cold circulating current has formed, in which the Atlantic, Pacific, Indian oceans participate. There were many processes that led to a general cooling on the Earth, as a result of which its polar regions were icy, forming cold desert regions. The climate has become harsh and arid.
Climatic zones of the continent
Antarctica is located in two climatic zones, called subantarctic and antarctic. In some places, at the northern end of the Antarctic Peninsula, a temperate zone may be observed . Only there is no division into polar day and night, but the conditions are still very harsh.
It should be noted that the Antarctic belt occupies almost the entire mainland. The continent is completely covered with ice, the thickness of which sometimes reaches 4.5 kilometers. It is because of this that Antarctica is considered the highest continent. Ice is the foundation of the entire existence of the continent. He submits not only the climate, but also the ecosystem of Antarctica. The icy masses reflect up to ninety percent of the sunlight, because of this the mainland is never warmed by the Sun. In continental areas, the climate is particularly severe, the temperature here drops to -64 degrees during the polar night, and in summer it can stay at -32. Strong winds blow from the depths of the mainland.
In the north of the Antarctic Peninsula there is a subantarctic belt. Here the living conditions are a little milder. In the summer, the temperature can even be slightly above zero. The ice cover here is not so thick, and in some places they reveal rocks with lichens and mosses on them. However, the influence of the inland regions of the continent is so great that conditions are completely unfavorable for people.
Antarctic zones
Meteorological observations conducted on the mainland made it possible to identify the characteristic climatic zones of Antarctica.
For example, an area of a high plateau, which is characterized by low temperatures, and the weather conditions in summer and winter do not really change. The air here is incredibly dry. Precipitation is very rare, and even then in the form of crystals.
The zone of the Antarctic slopes is characterized by strong winds all year round with heavy rainfall in the form of snowstorms.
But the coastal area is characterized by climatic diversity. There is instability in weather conditions, which is quite understandable by the proximity of the ice edge of the continent to warm oceanic waters. The entire coastal area suffers from the winds. In the summer, the temperature even rises to such a point that intense melting of the ice can be observed.
The drifting ice zone is located between the mainland shore and floating ice. Unstable weather reigns here with stormy, sharply changing winds, storms are often observed.
The Arctic open water zone is characterized by the absence of ice and at the same time low ocean temperature, solar heat hardly penetrates here, since the sky is hidden by dense clouds.
Antarctica Vegetation
Most of the mainland is an icy desert, time in Antarctica seems to have stopped. It is deprived not only of the plant, but also of the animal world, and of the human presence. Plants can only be found on the continental margins and on islets. Only the water pool is rich.
Of plants, only lichens, mosses, bacteria, fungi, and lower algae can be found here. The greatest riches are distinguished by lichens, numbering more than three hundred species. They are found on ice-free land. Mosses are present on the islands, forming even peatlands (80 varieties).
The simplest microscopic algae live in the summer in water bodies and on ice covers under the warm rays of the sun. Their accumulation creates green, red, yellow very bright spots. Algae colonies look like real green lawns.
But flowering plants on the mainland can not be found. Several species are present only on the Antarctic Peninsula.
Antarctica animals
Antarctica is not rich in terrestrial animals, there are no mammals here at all, there are simple worms, wingless and crustaceans. Freshwater fish do not live here. Only two species of birds nesting on one of the islands are known reliably.
The marine animal world is much richer. The Indian, Pacific, and Atlantic oceans are more habitable than the harsh icy surface of the mainland. Of particular interest are the huge jellyfish, reaching a weight of one hundred and fifty kilograms. Most fish are endemic. As for mammals, numerous whales and pinnipeds live here. Different types of seals live in different territories: some have chosen drifting ice, others are motionless. The elephant seal prefers the coast of the islands; at present, the abundance of this species has fallen significantly.
The largest mammals live in the waters of Antarctica - cetaceans: saivals, humpbacks, finwales, blue whales. The length of the largest such creature killed by whalers was thirty-three meters. In the mid-twentieth century, there was a decrease in the number of cetaceans due to their illegal capture. The basis of the nutrition of these huge creatures are small crustaceans, which are quite a lot in the cold ocean waters.
Bird world of the mainland
The bird world of the mainland is very peculiar. The birds live only near the water, eating small marine representatives and fish. The most famous among them are the penguins, whose wings are more like fins. They swim great, and at the same time they are completely unable to fly. They feed on mollusks, crustaceans and fish. Seventeen species of penguins live in Antarctica. The largest of them is the Imperial, whose weight reaches fifty kilograms. This unusual birds breed and raise their offspring in harsh conditions and at the same time feel quite comfortable.
Instead of an afterword
Harsh climatic conditions, due to many factors, left an imprint on the animal and plant world, making it rather small, since not every living organism is able to adapt to life in such harsh conditions.