The geographical location of Antarctica is the only one that practically did not raise doubts among numerous travelers who in ancient times went in search of the sixth continent. Unexplored land, according to their ideas, was located in the south of Africa and Australia. Antarctica was discovered there in 1820. The geographical position of the mainland is well known today. It is it that largely determines the severity of the climate and other conditions on the continent.
Geographical location of Antarctica: general information
In ancient times, Aristotle believed in the existence of a distant continent in the south. He reinforced his opinion with the theory of symmetry of the earth: a continent is necessary to balance its excess in the north. And, indeed, the icy continent is located in the southern polar region. The location opposite to the Arctic region of the globe was even reflected in its name. The prefix “anti” in translation from ancient Greek means “against”.
The geographical location of Antarctica is limited to an area called the Antarctic. It lies within 48-60º Yu. w. The area occupied by the mainland is estimated at 13,975 thousand square kilometers. This figure includes both ice shelves and islands connected to the continent. If, when calculating the area, the continental sandbank is also taken into account, then the indicator increases to 16,355 thousand km 2 .
Edge and Center
The geographical location of Antarctica is characterized by the presence of a long peninsula that stretches toward South America. Here is the northernmost point of the mainland. This is Cape Sifre. It reaches 63º13 'south latitude. On the opposite side of the peninsula, the territory of the ice continent does not protrude so far into the ocean.
The coordinates of the center of Antarctica are approximately 84º S. W and 64º in. e. He received the name "pole of relative inaccessibility." Opinions about its exact location differ somewhat. In science, the pole of inaccessibility is the point as far as possible from transport routes, in the case of the sixth continent - from the coast. However, several factors, including the geographical location of Antarctica, have made it difficult to determine its location. The coastline can be drawn along the "meeting point" of land and water, or on ice shelves and the ocean. Because of this, the exact coordinates of the inaccessibility pole are not defined. Often it is associated with the Soviet station of the same name, located at 82º06 'S. w. and 54º58 'in. d.
In any case, the location of the center of the continent does not coincide with the location of the South Pole. If the first of the indicated coordinates is chosen as the correct ones, then the distance between them is approximately 660 km.
Highest continent
Although studying the geographical position of Antarctica, Grade 7, few people remember how the continent "rises" above sea level. The sixth mainland is rightfully considered the highest. The reason is the impressive ice cover. On average, the surface height of Antarctica above sea level is two thousand meters. In the center of the continent, the figure rises to 4000 m. The vast majority of this power is ice. Only 0.3% of the relief of Antarctica is free of it. The surface height of the sixth continent is 2.8 times greater than that of any other continent.
Two parts
Ice-free zones include the Transantarctic Mountains. They divide the continent into two areas: West and East Antarctica. These areas vary in their structure and origin. The eastern part is a place where the continent's rather high plateaus are located, reaching four thousand meters above sea level. The western region is occupied by mountainous islands, interconnected by ice. In the same zone, on the Pacific coast, the Antarctic Andes are located, also exceeding 4 thousand meters above sea level. The highest point on the continent is the Vinson Massif. It is located in West Antarctica and rises to 4892 m. In the same part is the lowest point of the mainland. This is a Bentley hollow filled with ice. Its depth reaches 2555 m below sea level.
Impressive cover
The physical and geographical position of Antarctica is the key to understanding all the features of the mainland. It is the reason for such an impressive ice cover of the continent. A similar formation can be found in Greenland. However, the Antarctic ice blanket is ten times superior to it. The characteristics of this formation are striking. It contains 90% of all the ice that is on the land of our planet. Its volume is approximately 33 million cubic kilometers!
Ice cover is a formation resembling a dome. The steepness of its surface increases towards the coast. The gradual accumulation of mass leads to the movement of ice in the direction of its destruction (ablation, scientifically). For Antarctica, such a zone is the coast. Here the ice breaks, icebergs form. Annually, the total volume of destruction is approximately 2.5 thousand km 3 .
Feature
As you can see, the geographical location of Antarctica and the glacial relief are inextricably linked. The location of the continent caused another feature of the mainland. These are huge ice shelves. They, partially swimming in the water, partially leaning on the bottom, stretch from the coast to the sea. Ice shelves are the source of the most impressive icebergs in size. Some specimens amaze with their dimensions even scientists quite familiar with the wonders of the Antarctic. A good example is the B-15 iceberg, which broke away in 2000 from the Ross Ice Shelf. Its area exceeded ten thousand square kilometers.
In the winter period (in the Northern Hemisphere , summer is at this time), the territory occupied by ice shelves is estimated at 18 million km ² . When summer comes to replace it, their area is reduced to 3-4 million km ² .
Ancient education
According to researchers, the continental ice sheet formed about 14 million years ago. Not the last role in this was played by the erosion of the bridge, which had previously connected the sixth continent and South America. The “trace” from it is the Antarctic Peninsula. The same process, apparently, also led to the formation of the West winds (Atlantic circumpolar current), which separates the waters surrounding the mainland from the oceans.
Conditional boundary
The geographical position of Antarctica according to the plan of the area or map is determined including its proximity to the Atlantic, Pacific and Indian oceans. In some manuals, they directly border the continent. In others, Antarctica is washed by the waters of the Southern Ocean. Its conditional border can be called the course of the West winds. The allocation of the Southern Ocean is more likely to be informal, although from the beginning of our century it is increasingly found in the literature.
Temperature conditions in the waters washing the continent vary in the range from -2 º to +10 º. The Southern Ocean is a place of strong storms and winds. In winter, it freezes up to 65º. w. in the Pacific Ocean and up to 55º s. w. in the area of the Atlantic. However, some areas remain ice-free throughout the entire period due to strong winds.
Climate
The geographical location of Antarctica affects the weather conditions on the continent. Here is the cold pole of the planet. The lowest temperature (-88.3 º) was recorded by Soviet researchers in August 1960 at the Vostok station. Average winter values vary between -60 º and -70 º. In summer, the range is slightly different: from -30 º to -50 º. In general, the temperature almost never rises above -20 º. The exception is the coast and its most prominent point - the Antarctic Peninsula. Here in the summer the air can warm up to 10-12 º. In the winter months, the temperature on the peninsula drops to a level of -8 º insignificant by the standards of the continent. At the same time, the movement of cold air masses from the center of the continent “awakens” quite strong winds: sometimes their speed reaches 90 m / s.
Antarctica (geographical location contributes to this) is not famous for its high humidity values. The average figure is 60-80%, on the coast it decreases to 20%, and in some areas even to 5%. This fact is especially striking if you recall how much water is contained in the icy shell of the continent.
Once upon a time, Antarctica was covered in forests. According to researchers, there were rivers and lakes, mountains and hills, valleys and meadows on the continent. Today it is difficult to imagine such an Antarctica. Some of the discovered minerals, in particular coal deposits, testify to its past. However, many of the resources hidden by the ice cover have yet to be explored. The harsh conditions of modern Antarctica connected with its geographical location do not allow us to quickly explore the vast territories of the mainland. Perhaps that is why it was here that the program of international cooperation began to unfold. Researchers from different countries together are trying to comprehend the secrets of the sixth continent. And the degree of progress often depends on the ability to agree and coordinate actions.