The Indian Ocean is the third largest of all in terms of area. At the same time, in comparison with others, the greatest depth of the Indian Ocean is very modest - only 7.45 kilometers.
Location
It is not difficult to find it on the map - the Asian part of Eurasia is located in the north of the ocean, Antarctica lies on the southern shores, and Australia lies in the east from the east. In its western part is Africa.
Most of the ocean’s area is located in the southern hemisphere. A very conventional line separates the Indian and Atlantic oceans - from Cape Igolny in Africa, down the twentieth meridian to Antarctica itself. It is separated from the Pacific by the Indo-Chinese peninsulas of Malacca, the border goes to the north of Sumatra, then along the line that on the map connects the islands of Sumatra, Java, Sumba and New Guinea. With the fourth - the Arctic Ocean - the Indian Ocean has no common borders.
Area
The average depth of the Indian Ocean is 3897 meters. At the same time, it covers an area of 74,917 thousand kilometers, which allows it to be in third place among its "brothers" in size. The shores of this huge reservoir are cut very weakly - this is the reason why there are few seas in its composition.
Relatively few islands lie in this ocean. The most significant of them once broke away from the mainland, therefore they are located close to the coastline - Socotra, Madagascar, Sri Lanka. Offshore, in the open, you can find islands that originated from volcanoes. These are Crozet, Mascaren and others. In the tropics on the cones of volcanoes are islands of coral origin, such as the Maldives, Cocos, Adaman and others.
The shores in the east and northwest are indigenous, while in the west and northeast they are mostly alluvial. The edge of the coast is cut up very weakly, except for its northern part. This is where most of the large bays are concentrated.
Depth
Of course, the depth of the Indian Ocean cannot be the same on such a large area - the maximum is 7130 meters. This point is located in the Sunda Trench. At the same time, the average depth of the Indian Ocean is 3897 meters.
Sailors and researchers of water open spaces cannot be guided by an average figure. Therefore, scientists have long been compiled a map of the depths of the Indian Ocean. It accurately indicates the height of the bottom at various points, all the shallows, gutters, hollows, volcanoes and other features of the relief are visible.
Relief
Along the coast lies a narrow strip of mainland shallow, about 100 kilometers wide. The edge of the shelf, located in the ocean, has a shallow depth - from 50 to 200 meters. Only in northwestern Australia and along the Antarctic coast does it increase to 300-500 meters. The slope of the mainland is quite steep, in some places divided by the underwater valleys of large rivers, such as the Ganges, Indus and others. In the northeast, a fairly uniform bottom topography of the Indian Ocean is enlivened by the Sunda Island Arc. It is here that the Sunda Trench is located , in which the most significant depth of the Indian Ocean is discovered. The maximum point of this gutter is located 7130 meters below sea level.
Ridges, ramparts and mountains broke the bed into several basins. The most famous are the Arabian Basin, the African-Antarctic and the Western Australian. These depressions formed hilly, located in the center of the ocean, and accumulative plains located not far from the continents, in those areas where sediment is supplied in sufficient quantities.
Among the large number of ranges, the East Indian is especially noticeable - its length is about 5 thousand kilometers. However, the relief of the bottom of the Indian Ocean also has other significant ridges - the Western Australian, meridional and others. It is rich in bed and various volcanoes, places forming chains and even quite large massifs.
Mid-ocean ridges - three branches of the mountain system, dividing the ocean from the center to the north, southeast and southwest. The width of the ranges ranges from 400 to 800 kilometers, the height is 2-3 kilometers. The relief of the bottom of the Indian Ocean in this part is characterized by faults across the ridges. Along them, the bottom is most often shifted horizontally by 400 kilometers.
Unlike the ridges, the Australian-Antarctic Uplift is a rampart with gentle slopes, the height of which reaches a kilometer, and the width extends to one and a half thousand kilometers.
Mostly the tectonic structures of the bottom of this particular ocean are quite stable. Active developing structures occupy a much smaller area and flow into similar structures in Indochina and East Africa. These main macrostructures are divided into smaller ones: plates, block and volcanic ridges, banks and coral islands, gutters, tectonic ledges, troughs of the Indian Ocean and others.
Among the various irregularities, a special place is occupied by the north of the Mascarene ridge. Presumably, this part previously belonged to the long-lost ancient mainland of Gondwana.
Climate
The area and depth of the Indian Ocean make it possible to assume that the climate in its different sections will be completely different. And indeed it is. The northern part of this huge reservoir has a monsoon climate. In summer, during the period of low pressure over mainland Asia, south-west flows of equatorial air prevail over water. In winter, tropical air masses from the northwest dominate here.
A little south of 10 degrees south latitude, the climate over the ocean becomes much more constant. In tropical (and subtropical in summer) latitudes, southeast trade winds dominate here. In the temperate - extratropical cyclones that move from west to east. Hurricanes are often found in the west of tropical latitudes. Most often, they sweep in the summer and autumn.
The air in the north of the ocean warms up in the summer to 27 degrees. African coasts are blown with a temperature of about 23 degrees. In winter, the temperature decreases depending on latitude: in the south it can be below zero, while in the northern part of Africa the thermometer does not fall below 20 degrees.
Water temperature depends on currents. The coast of Africa is washed by the Somali current, which has rather low temperatures. This leads to the fact that the water temperature in this region is at a level of about 22-23 degrees. In the north of the ocean, the upper layers of the water can reach a temperature of 29 degrees, while in the southern regions, off the coast of Antarctica, it drops to -1. Of course, we are talking only about the upper layers, since the greater the depth of the Indian Ocean, the more difficult it is to draw conclusions about the temperature of the water.
Water
The depth of the Indian Ocean does not affect the number of seas at all. And there are fewer of them than in any other ocean. There are only two Mediterranean seas: the Red and the Persian Gulf. In addition, there are also the marginal Arabian Sea, the Andaman Sea - only partially closed. In the east of the vast waters are the Timor and Arafura Seas.
The largest rivers in Asia belong to the basin of this ocean: the Ganges, Saluin, Brahmaputra, Irvadi, Indus, Euphras and Tiger. Among the African rivers it is worth highlighting Limpopo and Zambezi.
The average depth of the Indian Ocean is 3897 meters. And here in this water column a unique phenomenon occurs - a change in the direction of currents. The currents of all other oceans are unchanged from year to year, while in the Indian currents are subject to winds: in winter they are monsoon, in summer - predominant.
Since deep waters originate in the Red Sea and the Persian Gulf, almost the entire mass of water has high salinity with a low percentage of oxygen.
The coast
In the west and northeast, predominantly alluvial shores, while in the northwest and east are indigenous. As already mentioned, the coastline is almost flat, indented very weakly over almost the entire length of this water body. An exception is the northern part - this is where most of the seas belonging to the Indian Ocean basin are concentrated.
The inhabitants
A fairly small average depth of the Indian Ocean boasts a wide variety of representatives of the animal and plant worlds. The Indian Ocean is located in the tropical and temperate zones. Shoals are full of corals and hydrocorals, among which a huge number of species of invertebrates live. These are worms, and crabs, and sea urchins, stars and other animals. No fewer brightly colored tropical fish find shelter in these areas. The coasts are rich in mangroves, in which the mud jumper has settled - this fish can live very long without water.
Flora and fauna of beaches subject to low tide are very poor, since the hot sun rays destroy everything living here. The temperate zone in this sense is much more diverse: there is a wide selection of algae and invertebrates.
The open ocean is even richer in living creatures - representatives of both the animal and plant worlds.
The main animals are copepods. More than a hundred of their species live in the waters of the Indian Ocean. Winged mollusks, siphonophores, jellyfish and other invertebrates are almost as good as the number of species. Several species of flying fish frolic in the ocean, sharks, luminous anchovies, tuna, sea snakes. Whales, pinnipeds, sea turtles, dugongs are no less common in these waters.
Feathered inhabitants are represented by albatrosses, frigates and several species of penguins.
Minerals
In the waters of the Indian Ocean, oil deposits are being developed. In addition, the ocean is rich in manganese ores, phosphates, potash raw materials necessary for fertilizing agricultural land.