The geographical position of the Indian Ocean: description, features. Indian Ocean on the map

From the tropics to the ice of Antarctica

The Indian Ocean is located between four continents - Eurasia (the Asian part of the continent) in the north, Antarctica in the south, Africa in the west and east with Australia and a group of islands and archipelagos located between the Indochinese Peninsula and Australia.

Most of the Indian Ocean is located in the southern hemisphere. The border with the Atlantic Ocean is determined by a conditional line from Cape Igolny (the southern point of Africa) along the 20th meridian to Antarctica. The border with the Pacific Ocean runs from the Malay Peninsula (Indochina) to the northern point of Sumatra, then along the line. connecting the islands of Sumatra, Java, Bali, Sumba, Timor and New Guinea. Between New Guinea and Australia, the border passes through the Torres Strait, south of Australia - from Cape Howe to Tasmania and along its western coast, and from Cape Yuzhny (the southernmost point of Tasmania) strictly along the meridian to Antarctica. The Indian Ocean does not border the Arctic Ocean.

You can see a complete map of the Indian Ocean.

The area occupied by the Indian Ocean - 74917 thousand square kilometers - is the third largest ocean. The coastline of the ocean is slightly indented, so there are few marginal seas. In its composition, only such seas as the Red Sea, the Persian and Bengal Bays (in fact, these are huge marginal seas), the Arabian Sea, the Andaman Sea, the Timor and Arafura Seas can be distinguished. The Red Sea is inland sea basins, the rest are marginal.

The central part of the Indian Ocean consists of several deep-sea basins, among which the largest are the Arabian, West Australian, African-Antarctic. These basins are separated by long underwater ridges and uplifts. deepest point Indian Ocean - 7130 m located in the Sunda Trench (along the Sunda island arc). The average depth of the ocean is 3897 m.

The bottom relief is rather monotonous, the eastern part is more even than the western one. There are many shoals and banks in the region of Australia and Oceania. The bottom soil is similar to the soil of other oceans and represents the following types: coastal sediments, organic silt (radiolar, diatom) and clay - at great depths (the so-called "red clay"). Coastal deposits are sand located in shallows to a depth of 200-300 m. Silt deposits can be green, blue (near rocky coasts), brown (volcanic areas), lighter (due to the presence of lime) in areas of coral buildings. Red clay occurs at depths greater than 4500 m. It has a red, brown, or chocolate color.

In terms of the number of islands, the Indian Ocean is inferior to all other oceans. The largest islands: Madagascar, Ceylon, Mauritius, Socotra and Sri Lanka are fragments of ancient continents. In the central part of the ocean there are groups of small islands of volcanic origin, and in tropical latitudes - groups of coral islands. The most famous groups of islands: Amirante, Seychelles, Comorno, Reunion, Maldives, Cocos.

water temperature in the ocean currents are determined by climatic zones. The cold Somali Current lies near the coast of Africa, here the average water temperature is + 22- + 23 degrees C, in the northern part of the ocean the temperature of the surface layers can rise to + 29 degrees C, at the equator - + 26- + 28 degrees C, according to as you move south, it drops to -1 deg. C off the coast of Antarctica.

The flora and fauna of the Indian Ocean is rich and varied. Many tropical coasts are mangroves, where special communities of plants and animals have formed, adapted to regular flooding and drainage. Among these animals, one can note numerous crabs and an interesting fish - the mudskipper, which inhabits almost all the mangroves of the ocean. The shallow tropical waters are home to coral polyps, including many reef-building corals, fish and invertebrates. AT temperate latitudes, red and brown algae grow in abundance in shallow water, among which the most numerous are kelp, fucus and giant macrocysts. Phytoplankton is represented by peridineans in tropical waters and diatoms in temperate latitudes, as well as blue-green algae, which form dense seasonal aggregations in some places.

Among the animals living in the Indian Ocean, most of all are rhizopods, of which there are over 100 species. If we weigh all the rootpods in the waters of the ocean, then their total mass will exceed the mass of all its other inhabitants.

Invertebrates are represented by various molluscs (pteropods, cephalopods, valvular, etc.). A lot of jellyfish and siphonophores. In the waters of the open ocean, as in the Pacific Ocean, flying fish, tuna, dolphins, sailboats and luminous anchovies are numerous. There are many sea snakes, including poisonous ones, even a combed crocodile is found, prone to attacking people.

Mammals are represented by a large number and variety. There are whales here too. different types, and dolphins, and killer whales, and sperm whales. Many pinnipeds (fur seals, seals, dugongs). Cetaceans are especially abundant in the cold southern waters of the ocean, where krill feeding grounds are found.

Among those living here sea ​​birds frigatebirds and albatrosses can be noted, and in cold and temperate waters - penguins.

Despite the richness of the fauna of the Indian Ocean, fishing and fishing in this region are poorly developed. The total catch of fish and seafood in the Indian Ocean does not exceed 5% of the world catch. Fishing is represented only by tuna fishing in the central part of the ocean and by small fishing teams and individual fishermen of the coasts and island regions.
In some places (off the coast of Australia, Sri Lanka, etc.) pearl mining is developed.

Life is also present in the depths and bottom layer of the central part of the ocean. In contrast to the upper layers, which are more adapted for the development of flora and fauna, the deep-water areas of the ocean are represented by a smaller number of individuals of the animal world, but in terms of species they surpass the surface. Life in the depths of the Indian Ocean has been studied very little, as well as the depths of the entire World Ocean. Only the contents of deep-sea trawls, and rare dives of bathyscaphes and similar devices into many kilometers of depths, can approximately tell about the local life forms. Many forms of animals that live here have forms of bodies and organs that are unusual for our eyes. Huge eyes, a toothy head larger than the rest of the body, bizarre fins and outgrowths on the body - all this is the result of animals adapting to life in conditions of pitch darkness and monstrous pressures in the depths of the ocean.

Many of the animals use luminous organs, or the light emitted by some benthic microorganisms (benthos) to attract prey and protect themselves from enemies. So, a small (up to 18 cm) platytroct fish, found in the deep zones of the Indian Ocean, uses luminescence for protection. In moments of danger, she can blind the enemy with a cloud of glowing slime and safely flee. Many living creatures that live in the dark depths of the deep-sea regions of the oceans and seas have similar weapons. great white shark. There are many shark-hazardous places in the Indian Ocean. Off the coast of Australia, Africa, the Seychelles, the Red Sea, Oceania, shark attacks on people are not uncommon.

There are many other animals dangerous to humans in the Indian Ocean. Poisonous jellyfish, blue-ringed octopus, cone mollusks, tridacnids, poisonous snakes, etc. can cause serious communication problems for a person.

The following pages will tell about the seas that make up the Indian Ocean, about the flora and fauna of these seas, and, of course, about the sharks living in them.

Let's start with the Red Sea - a unique inland water body of the Indian Ocean basin

And the island of Timor and further in the west and northwest along the Lesser Sunda Islands, the islands of Java, Sumatra and the Malay Peninsula. Includes the Red Sea and the Persian Gulf, marginal seas - Arabian and Andaman, large bays - Aden, Oman, Bengal, Great Australian. Islands of the Indian Ocean - of continental origin - Madagascar, Tasmania, Sri Lanka, Socotra, Seychelles, surface peaks of volcanoes - Kerguelen, Crozet, Prince Edward, Amsterdam, Saint-Paul, coral atolls - Laccadive, Maldives, Chagos, Cocos, etc. , volcanic islands, bordered by coral reefs - Mascarene, Comoros, etc.

General information. The third largest basin of the World Ocean, the area with the seas is 76.17 million km 2, the average depth is 3711 m; the volume of water is 282.7 million km 3. Includes internal (Red Sea and Persian Gulf) and marginal seas (Arabian, Andaman and Antarctic seas - Lazarev, Riiser-Larsen, Cosmonauts, Commonwealth, Davis, Mawson, D'Urville); large bays - Aden, Oman, Bengal, Great Australian. Islands of continental origin - Madagascar (area 596 thousand km 2), Tasmania (over 68 thousand km 2), Sri Lanka (65.6 thousand km 2), Socotra (3.6 thousand km 2), Seychelles (405 km 2) ; volcanic islands - Crozet (about 200 km 2), Amsterdam (66 km 2) and others, coral atolls - Laccadive (28 km 2), Maldives (298 km 2), Chagos (195 km 2), Cocos (22 km 2 ) and etc.; volcanic islands bordered by coral reefs - Mascarene (4.5 thousand km 2), Andaman (6.5 thousand km 2), etc.

Historical outline. The first voyages in the Indian Ocean were made in the 5th millennium BC. Sumerians (in the Persian Gulf); in the 6th c. BC. The Phoenicians from the Red Sea entered the Indian Ocean and traveled along the coast of Africa. At the beginning of a.d. ships of Indians, Chinese and Arabs develop trade routes along the coasts of the continents. In the 8th to 10th centuries, there were permanent maritime trade links between China and India. In the 14th century, an expedition led by the Arab Ibn Battuta bypassed almost the entire western and northern coast of the Indian Ocean. In the era of the Great Geographical Discoveries, Europeans mastered the sea routes in the Indian Ocean (the expeditions of the Portuguese P. Covilhã - 1489-92, Vasco da Gama - 1497-99, the Englishman J. Cook - 1772-75, etc.). Systematic trade relations were established between the Portuguese, and then the Dutch, with the peoples inhabiting the coast of the Indian Ocean. The first oceanographic observations in the Indian Ocean (mainly measuring the temperature and depth of the water) began in the late 18th and early 19th centuries, including in Russian expeditions on the ships Neva and Nadezhda (1803-06), Rurik (1815 -18), "Mirny" and "Vostok" (1819-21), "Enterprise" (1823-26) and others. However, the first actual oceanographic expedition was a round-the-world voyage on the English ship Challenger (1872-76), in which numerous information was obtained about the physics of the sea, the chemical composition of waters, the biology and geology of the World Ocean (including the Indian Ocean). The period of the late 19th and early 20th centuries is characterized by the accumulation of factual materials on the oceanology of the Indian Ocean. Important materials were obtained during regular Antarctic expeditions of the Soviet ships Slava (beginning in 1946 and 1955). In 1960-65, the International Indian Ocean Expedition was carried out, in which more than 40 ships from 13 countries participated, including more than 10 scientific ships. A major contribution to the study of the geology of the Indian Ocean was made by deep-sea drilling of the bottom during 22-29 voyages of the Glomar Challenger drill ship in 1972-73 (more than 60 wells were drilled).

Hydrological regime. In the circulation of surface waters in the Indian Ocean, 3 large-scale circulation systems are clearly distinguished: the seasonally changing monsoon circulation, the southern subtropical, anticyclonic circulation, and the Antarctic Circumpolar Current. During the northeast monsoon (northern hemisphere winter), the monsoon cycle is represented by the north trade wind current (Northeast monsoon current), the current following south along the Somali Peninsula, and the Intertrade (equatorial) countercurrent. During the southwest monsoon (summer of the northern hemisphere), the monsoonal cycle consists of the northern edge of the south trade wind current, the Somali current and the southwest monsoon current, which merges with the equatorial countercurrent. The boundary between the monsoonal and southern subtropical gyres is located at approximately 15° south latitude. Separate links of the subtropical circulation represent the southern trade wind current, the Agulhas current, the South Indian Ocean and the weak West Australian current. The Antarctic Circumpolar Current is located between the Subantarctic Front (Subtropical Convergence), which is the southern boundary of the Subtropical Gyre, and the Antarctic Divergence. Near the coast of Antarctica, there are weak cyclonic gyres.

The Indian Ocean crosses all the climatic zones of the southern hemisphere (see map). The northern part of the ocean is located in the equatorial and subequatorial belts, and only partially (the Red Sea, the Persian Gulf and part of the ocean, the sea south of the coast of the Arabian Peninsula) is in the tropical zone of the northern hemisphere. The average temperature of the ocean waters is 3.8°C, the maximum average annual temperatures exceeding 27.5°C are characteristic of the equatorial zone (the highest temperature, over 34°C, is observed in August in the Persian Gulf). In the Antarctic zone, the surface water temperature drops to 1°C. The maximum salinity values ​​(40-41°/oo) are observed in the Persian Gulf and the Red Sea, in the Antarctic zone - 34.87°/oo; in the open ocean, the highest values ​​are characteristic of the southern subtropical zone (about 36°/oo). In areas with a humid climate and intense river flow (the Bay of Bengal, the Australo-Asian seas), the waters are heavily desalinated. According to thermohaline characteristics, 4 main layers are distinguished vertically. The distribution of the upper water layers is subject to latitudinal zonality; the deep and near-bottom layers are characterized by meridional water transport. Antarctic bottom waters, which form in the highest southern latitudes, dominate the bottom layer of the entire Indian Ocean.

Ice. The ice of the Indian Ocean is distributed only in Antarctic waters and is mainly seasonal; multi-year ice occurs only in a narrow strip along Antarctica. In August - September, floating ice reaches 55 ° south latitude, in February - March, the northern limit of their distribution retreats south to 65-68 ° south latitude. 35° south latitude.

Relief and geological structure. Within the Indian Ocean, their underwater margins (passive continental margins) stretch along the coasts of the continents, within which the continental crust, which is thinning towards the ocean, borders on the oceanic one. In the northeast, the ocean is bounded by a complexly constructed transition zone (an active margin, a zone of absorption of lithospheric plates), which includes the Sunda island arc and a deep-water trench. The width of the shelves almost everywhere does not exceed several tens of kilometers, only in the area of ​​Cape Agulhas at the southern tip of Africa, off the western coast of Hindustan and the northwestern coast of Australia, does it increase to 300-350 km. See map.

The edge of the shelf is located mainly at a depth of 100-200 m (near Antarctica up to 400-500 m).

Within the ocean floor, a system of mid-ocean ridges (Arabian-Indian, West Indian, African-Antarctic, Central Indian, Australo-Antarctic) is distinguished, which in the region of the Gulf of Aden and the Red Sea is connected to intracontinental rift systems (see maps). The total length of the mid-ocean ridges of the Indian Ocean is about 20 thousand km, the width varies from 400 to 1000 km or more, and the height is from 2.5 to 4 km. In the axial part of the ridges, the sedimentary cover (corresponding to the 1st layer of the crust) is absent or distributed fragmentarily, and basalts of the 2nd layer of the crust are exposed on the surface (seismic wave velocity 4.5-5.5 km/s) with a thickness of several km. Under them lie rocks (representing, apparently, decompacted mantle, speed 7-7.5 km / s) with a thickness of 8-11 km. The ridges are dissected by numerous transform faults, in the walls of which a complete section is exposed oceanic crust. The lower part of the section is composed of ultramafic rocks, strongly serpentinized in places. Above lies gabbro, within which there are separate zones (possibly "layers") of pyroxenite composition, as well as secant veins of plagiogranite composition and gabbro-diabase dikes. Gabbro-diabases form a separate layer overlying the gabbro layer. The upper part of the section is represented by basalt pillow lavas, in places unevenly overlain by sedimentary formations.

The Mid-Indian Ridge divides the ocean floor into three segments, within which there are about 20 deep-sea basins. The following basins are located in the northeastern sector: Oman, Arabian, Central, Cocos, North Australian, West Australian, Naturalista, South Australian; in the western sector - Somali, Amirante, Mascarene, Madagascar, Comoros, Mozambique and Agulhas; in the Antarctic sector - Crozet, African-Antarctic, Australo-Antarctic. Sometimes smaller basins are distinguished. The degree of dissection of the relief is maximum near the median ridges and decreases with distance from them in areas of intensive accumulation of sedimentary material. In the basins, the thickness of the sedimentary cover lying on the basalt basement varies mainly from less than 100 m to 1000 m. a large amount of sedimentary material carried by rivers from the Asian mainland. The sedimentary cover, according to geophysical data and materials from deep-water drilling, is underlain by a basalt layer (2nd layer), characterized by a seismic wave speed of 5-5.5 km/s and a thickness of 1-3 km. The rocks of the 3rd layer lie below at a speed of 6.5-7 km/s and a thickness of 3-5 km. The average thickness of the earth's crust in the basins of the Indian Ocean is 6 km. The relief of the bed is complicated by more than ten large ridges and massifs, some of which (the Madagascar ridge, part of the Mascarene ridge with the bank of the Seychelles and the bank of the Saya de Mella, the Agulhas Upland) have continental crust.

The distribution of precipitation in the Indian Ocean clearly shows latitudinal-climatic, circum-continental, and vertical zonality. Terrigenous sediments are developed along the continents along the periphery of the oceans. In the ocean pelagic at a depth of less than 4000 m, carbonate foraminiferal and coccolith oozes are almost ubiquitous. At great depths in highly productive (humid) equatorial and Antarctic zones, they are replaced by siliceous (diatom and radiolarian-diatom) silts, and in low-productive (arid) -

India, immersed in ocean waves, attracts tourists from all over the world. Especially attracts vacationers Goa. Tour operators promise a lot of impressions and completely different beaches. To get the most out of swimming, you need to know what Goa bathes. Then the waves and sand will make you come back more than once.

What bathes Goa

When wondering what kind of sea awaits on the coast, be prepared to receive different answers.

Most commonly referred to as the Arabian Sea. However, its currents are an integral part of the ocean in Goa.

Hindustan, on which India is located, gave the name to the third largest water area of ​​\u200b\u200bthe Earth. That is why inexperienced travelers get lost and cannot decide whether the Arabian Sea or the Indian Ocean is a tourist paradise.

Some features of a sea holiday in Goa

The majestic and many-sided Indian Ocean occupies a huge space and is the biggest attraction of the state.

Here it has its own characteristics:

1. You can swim all year round.

   Indian Ocean on the map

   The sea warms up to 28 degrees, deviations of a couple of degrees do not play the role of the weather. Despite this, swimming after sunset at any time of the year is not worth it, stingrays and sea snakes are activated;

2. You can enjoy the Indian Ocean for free. The coast is absolutely free and is under the care of the municipality. No hotel has the right to block access to the beach. Buildings are located no closer than 200 m.;
3. The Arabian Sea is great for diving, especially in the bays and coves.

   Although the underwater world is significantly inferior to the diversity of other recognized water areas. The Indian Ocean washing the resort creates a lot of waves. The water is often cloudy due to the strong current. The Red or Mediterranean Seas are much richer in flora and fauna and more transparent;

4. The coastline, which is always washed by a warm current, leaves much to be desired in cleanliness. But this salient feature India. Water here is designed not only to wash the shores, but also to wash away garbage from them.

In fact, India attracts tourists with its authentic culture, tropical nature, the opportunity to touch the thousand-year history and original philosophy, especially in Goa.

The sea or the ocean washes the coast - it does not matter at all. The main thing is the sun and nature in the heart of an oriental fairy tale.

Indian Ocean - area and location

INDIAN OCEAN (Geography)

Location: body of water between Africa, Southern Ocean, Asia and Australia.
Geographical coordinates: 20° 00′ S

latitude, 80° 00′ E d.
Reference map:
Square: total: 68.556 million square kilometers; note: includes Andaman Sea, Arabian Sea, Bay of Bengal, Great Australian Gulf, Gulf of Aden, Gulf of Oman, Mozambique Channel, Persian Gulf, Red Sea, Malacca Strait and other bodies of water.
Comparative area: about 5.5 times the size of the US.
Land borders:
Coastline: 66,526 km.
Maritime claims:
Climate: northeast monsoons (December to April), southwest monsoons (June to October); tropical cyclones occur during May-June and October-November in the northern Indian Ocean and January-February in the southern Indian Ocean.
Relief: the ocean surface is dominated by broad circular, counterclockwise currents in the southern Indian Ocean; the unique reverse direction of surface currents in the northern Indian Ocean; low atmospheric pressure over Southwest Asia, due to warm rising summer air currents, results in southwest monsoons and southwest–northeast currents, while high pressure over northern Asia, due to cold descending winter air currents, leads to the emergence of northeast monsoons and currents directed from northeast to southwest; the ocean floor is dominated by the Central Indian Ridge and the Southwest Indian Ridge, the Southeast Indian Ridge, and the 90° E Ridge are located.
Maximum and minimum heights: lowest point: Yavan depression -7,258 m; highest point: sea level 0 m.
Natural resources: oil and gas reserves, fish, shrimp, sand and gravel deposits, gold sand deposits, polymetallic ore deposits on the ocean floor.
Land use:
Irrigated lands:
Natural Hazards:
Current environmental issues: endangered species of marine animals, including dugongs, seals, turtles and whales; oil pollution of the Arabian Sea, the Persian Gulf and the Red Sea.
International agreements on environmental protection:
Note to the section "Geography": the areas of the most intensive shipping are the Bab el-Mandeb Strait, the Strait of Hormuz, the Strait of Malacca, the southern entrance to the Suez Canal and drinking Lombok.

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Geographical position. The Pacific (or Great) Ocean is unique in size and nature natural object our planet. The ocean is located in all hemispheres of the Earth, between the continents of Eurasia and Australia in the west, North and South America in the east and Antarctica in the south.

The Pacific Ocean occupies more than 1/3 of the planet's surface and almost half of the World Ocean.

It has an oval outline, is somewhat elongated from the northwest to the southeast, and is widest between the tropics. The coastline is relatively straight off the North and South America and heavily dissected off the coast of Eurasia.

Where is the Indian Sea on the map

The Pacific Ocean includes a number of marginal seas of the Eastern and South-East Asia. In the ocean, a large number of archipelagos and individual islands(for example, as part of Oceania).

Bottom relief. The Pacific Ocean is the deepest. Its bottom relief is complex. The shelf (continental shoal) occupies a relatively small area. Off the coast of North and South America, its width does not exceed tens of kilometers, and off the coast of Eurasia, the shelf is measured in hundreds of kilometers.

Deep-sea trenches are located in the marginal parts of the ocean, and the main part of the deep-sea trenches of the entire World Ocean is located in the Pacific Ocean: 25 out of 35 have a depth of more than 5 km; and all trenches with a depth of more than 10 km - there are 4 of them. Large uplifts of the bottom, individual mountains and ridges divide the ocean floor into basins.

In the southeast of the ocean, the East Pacific Rise is located, which is part of the global system of mid-ocean ridges.

An almost continuous chain of active volcanoes is connected with the system of deep-sea trenches and mountain structures on the continents and islands adjacent to the ocean, forming the Pacific “Ring of Fire”. Earthquakes and underwater earthquakes are also frequent in this zone, causing giant waves - tsunamis.

The Pacific Ocean stretches from subarctic to subantarctic latitudes, that is, it is located in almost all climatic zones of the Earth. Its main part is located in the equatorial, subequatorial and tropical zones of both hemispheres.

The air temperature over the water area of ​​these latitudes is from +16 to +24°С throughout the year. However, in the north of the ocean in winter it drops below 0°C. Near the coasts of Antarctica, this temperature is maintained even in the summer months.

The circulation of the atmosphere over the ocean is characterized by zonal features: westerly winds prevail in temperate latitudes, trade winds dominate in tropical latitudes, and monsoons are pronounced in subequatorial latitudes off the coast of Eurasia. Over the Pacific Ocean strong winds storm force and tropical cyclones - typhoons.

The maximum amount of precipitation falls in the western parts of the equatorial belt (about 3000 mm), the minimum - in the eastern regions of the ocean between the equator and the southern tropic (about 100 mm).

currents. The Pacific Ocean is quite strongly elongated from west to east and therefore latitudinal water flows predominate in it.

Two huge rings of water movement are formed in the ocean: northern and southern. The Northern Ring includes the North Trade Wind, Kuroshio, North Pacific and California currents. The southern ring is made up of the South Equatorial, East Australian, Western Winds Current and Peruvian Current.

Currents have a significant impact on the redistribution of heat in the ocean and on the nature of adjacent continents - geoglobus.ru. Thus, trade wind currents drive warm waters from the western tropical coasts of the continents to the eastern ones, therefore, at low latitudes, the western part of the ocean is much warmer than the eastern one. In middle high latitudes, on the contrary, the eastern parts of the ocean are warmer than the western ones.

Water properties.

All types of surface water masses are formed in the Pacific Ocean, except for the Arctic ones. because of large area ocean between the tropics, its surface waters are warmer than other oceans. The average annual water temperature between the tropics is +19°C, in equatorial latitudes - from +25 to +29°C, off the coast of Antarctica - drops to -1°C. Precipitation falling over the ocean generally dominates evaporation.

The salinity of the surface waters of the Pacific Ocean is slightly lower than in the Atlantic, since the western part of the ocean receives a lot of fresh water. river waters(Amur, Huang He, Yangtze, Mekong and others). Ice phenomena in the northern part of the ocean and in the subantarctic belt are seasonal. Off the coast of Antarctica sea ​​ice last all year. Antarctic icebergs with surface currents rise to 40°S.

organic world.

In terms of biomass and number of species, the organic world of the Pacific Ocean is richer than in other oceans. This is due to its long geological history, huge size, variety of environmental conditions.

Organic life is especially rich in equatorial-tropical latitudes, in areas where coral reefs develop. In the northern part of the ocean, there are many different types of salmon fish.

Fishing in the Pacific Ocean accounts for more than 45% of the world's catch. The main fishing areas are areas of interaction between warm and cold waters; shelf areas in the west of the ocean and areas of deep water rise off the coast of North, and especially South, America.

natural complexes. In the Pacific Ocean there are all natural belts, except for the north polar one. The northern polar belt occupies a small part of the Bering and Okhotsk seas.

In this belt, there is an intensive circulation of water, so they are rich in fish. The northern temperate zone occupies vast water areas. It is characterized by the interaction of warm and cold water masses. This contributes to the development of the organic world. In the west of the belt, a unique aquatic complex of the Sea of ​​Japan is formed, which is distinguished by a large species diversity.

The northern subtropical belt in the Pacific Ocean is not as pronounced as the temperate one. The western part of the belt is warm, the eastern part is relatively cold.

The waters are slightly mixed, blue, transparent. The number of plankton and fish species is low.

The Northern Tropical Belt is formed under the influence of the powerful Northern Tradewind Current. There are many separate islands and archipelagos in this belt.

The productivity of the belt's waters is low. However, near the underwater heights and islands, where the vertical movement of the waters increases, accumulations of fish and other marine organisms appear.

In the equatorial belt, there is a complex interaction of winds and various currents.

At the boundaries of flows, eddies and gyres contribute to the rise of waters, therefore their biological productivity increases. Aquatic complexes near the Sunda Islands and the shores of Northeast Australia, as well as coral reef complexes, are the richest in life.

In the southern hemisphere in the Pacific Ocean, similar natural belts are formed as in the northern hemisphere, but they differ in some properties of water masses and the composition of organisms.

For example, notothenia and white-blooded fish live in the waters of the subantarctic and antarctic belts. In the southern tropical zone between 4 and 23 ° S.l. a special aquatic complex is being formed off the coast of South America.

It is characterized by a steady and intensive rise of deep waters (upwelling), the active development of organic life. This is one of the most productive areas of the entire oceans.

Economic use.

The Pacific Ocean and its seas wash the coasts of the continents, on which there are more than 30 coastal states with a total population of about 2 billion people. The main types of natural resources of the ocean are its biological resources. Ocean waters are characterized by high productivity (about 200 kg/km2). AT last years The Pacific Ocean ranks first in the world in the production of fish and seafood - geoglobus.ru. Mining began on the ocean shelf: deposits of oil and gas, tin ores and other non-ferrous metals; from sea water, table and potassium salts, magnesium, and bromine are obtained.

World and regional shipping routes pass through the Pacific Ocean, and a large number of ports are located on the ocean shores.

The most important lines run from the shores of North America to the Far East shores of Asia. The energy resources of the Pacific waters are large and varied, but are still underused.

Human economic activity has led to severe pollution of some areas of the Pacific Ocean. This was especially evident off the coast of Japan and North America.

The stocks of whales, a number of valuable species of fish and other animals have been depleted. Some of them have lost their former commercial value.

Position of the Indian Ocean
Or where is the Indian Ocean

First of all, the Indian Ocean is the youngest on Earth. It is located mainly in the Southern Hemisphere. Four continents surround it. In the north - the Asian part of Eurasia, in the west Africa, in the east Australia and Antarctica in the south.

Along the line from Cape Agulhas, the southernmost point of Africa, and along the twentieth meridian to Antarctica, its waves merge with the Atlantic. The Indian Ocean borders the Pacific Ocean in the north from the western coast of the Malay Peninsula to the northern point of the island of Sumatra and further along the islands of Sumatra, Java, Bali, Sumba, Timor and New Guinea.

There was a lot of controversy among geographers about the eastern border. But now it seems that everyone has agreed to count it from Cape York in Australia, through the Torres Strait, New Guinea and further northeast through the Lesser Sunda Islands to the islands of Java, Sumatra and the city of Singapore. Between the islands of New Guinea and Australia, its border runs along the Torres Strait. In the south, the ocean boundary runs from Australia to the western coast of Tasmania and further along the meridian to Antarctica.

Semi-enclosed part of the Indian Basin - Arabian Sea on the map

Thus, when viewed from space, the Indian Ocean is shaped like a triangle ...

What is the area of ​​the Indian Ocean?

The Indian Ocean is the third largest after the Pacific and Atlantic (area Atlantic Ocean), its area is 74,917 thousand square kilometers.

Seas of the Indian Ocean

The shores of the bordering continents are slightly indented, therefore there are very few seas in it - in the north it is the Red Sea, the Persian Gulf, the Arabian Sea, the Bay of Bengal and the Andaman Sea, and in the east - the Timor and Arafura Seas.

Depth of the Indian Ocean

At the bottom of the Indian Ocean, in its central part, there are several deep-water basins separated by underwater ridges and underwater plateaus, and along the Sunda island arc there is deep water Sunda Trench.

In it, oceanologists have found the most deep hole on the ocean floor - 7130 meters from the surface of the water. The average depth of the ocean is 3897 meters. The largest islands in the Indian Ocean are Madagascar, Socotra and Sri Lanka.

All of them are fragments of ancient continents. In the central part of the ocean there are groups of small volcanic islands, and in tropical latitudes there are quite a lot of coral islands.

Temperature of the Indian Ocean

The water in the Indian Ocean is warm. In June - August, closer to the equator, its temperature, as in a bath, is 27-28 ° C (and there are places where the thermometer shows 29 ° C). And only off the coast of Africa, where the cold Somali current passes, the water is colder - 22-23 ° С.

But from the equator south to the Antarctic, the temperature of the water in the ocean changes to 26 and even 28 ° C. From the north, it is limited by the shores of the Eurasian continent. From the south - a conditional line connecting the extremities South Africa and Australia.

West is Africa.

Which ocean is the warmest?

But why is the Indian Ocean considered the youngest? The geographical map clearly shows how its basin is surrounded by continental landmasses. In the not so distant geological past of our planet, these areas were most likely connected into a single mainland Gondwana, which split, and its parts spread out in different directions, making room for water.

At the bottom of the Indian Ocean, scientists have discovered several underwater mountain ranges.

And The Central Indian Range divides the ocean basin into two regions. with absolutely different types earth's crust. Deep cracks adjoin the seamounts. Such proximity inevitably causes frequent earthquakes in these areas, or rather, seaquakes. As a result, tsunamis are born, which bring incalculable troubles to island and coastal mainland residents.

Submarine volcanoes in these restless regions eject so much material from the depths that from time to time new islands appear in the seismic belts.

Many coral reefs and atolls are found in the local warm waters. Driving ships in the Indian Ocean is not easy. During stormy periods, in some of its areas, huge waves as high as a five-story building were registered! .. Giant catastrophic waves tsunamis are not such a rare exotic for the inhabitants of the Indian Ocean basin.

Indian Ocean is component world ocean. Its maximum depth is 7729 m (Zonda Trench), and the average depth is just over 3700 m, which is the second result after the depths of the Pacific Ocean. The size of the Indian Ocean is 76.174 million km2. This is 20% of the world's oceans. The volume of water is about 290 million km3 (together with all the seas).

The waters of the Indian Ocean are distinguished by their light blue color and good transparency. This is due to the fact that very few freshwater rivers flow into it, which are the main "troublemakers". By the way, due to this, the water in the Indian Ocean is much saltier compared to the salinity of other oceans.

Location of the Indian Ocean

Most of the Indian Ocean is in the Southern Hemisphere. It borders Asia to the north, Antarctica to the south, Australia to the east, and the African continent to the west. In addition, in the southeast, its waters connect with the waters of the Pacific Ocean, and in the southwest with the Atlantic Ocean.

Seas and gulfs of the Indian Ocean

The Indian Ocean does not have as many seas as other oceans. For example, in comparison with the Atlantic Ocean, they are 3 times less. Most of the seas are located in its northern part. In the tropical zone are: Red (the most salty sea on Earth), Laccadive, Arabian, Arafura, Timor and Andaman seas. The Antarctic zone hosts the d'Urville, Commonwealth, Davis, Riiser-Larsen, Cosmonauts seas.

The largest bays of the Indian Ocean are the Persian, Bengal, Oman, Aden, Prydz and the Great Australian.

Indian Ocean Islands

The Indian Ocean is not distinguished by an abundance of islands. Largest islands having a mainland origin - Madagascar, Sumatra, Sri Lanka, Java, Tasmania, Timor. Also, there are volcanic islands, such as Mauritius, Renyon, Kerguelen, and coral - Chagos, Maldives, Andaman, etc.

Underwater world of the Indian Ocean

Since more than half of the Indian Ocean is located in the tropical and subtropical zones, its underwater world is very rich and diverse in terms of species. coastal zone in the tropics, it abounds with numerous colonies of crabs and unique fish - mudskippers. Corals live in shallow waters, and various algae grow in temperate waters - calcareous, brown, red.

The Indian Ocean is home to dozens of species of crustaceans, molluscs and jellyfish. A fairly large number of sea snakes also live in the ocean waters, among which there are also poisonous species.

Sharks are a special pride of the Indian Ocean. Its waters are plowed by many species of these predators, namely tiger, mako, gray, blue, great white sharks, etc.

Mammals are represented by killer whales and dolphins. Several species of pinnipeds (seals, dugongs, seals) and whales live in the southern part of the ocean.

Despite all the richness of the underwater world, seafood fishing in the Indian Ocean is rather poorly developed - only 5% of the world's catch. Sardines, tuna, shrimp, lobsters, rays and lobsters are harvested in the ocean.

1. ancient name Indian Ocean - East.

2. In the Indian Ocean, ships are regularly found in good condition, but without a crew. Where he disappears is a mystery. Over the past 100 years, there have been 3 such ships - Tarbon, Houston Market (tankers) and the Cabin Cruiser.

3. Many species of the underwater world of the Indian Ocean have a unique property - they can glow. This is what explains the appearance of luminous circles in the ocean.

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The Indian Ocean has the fewest seas compared to other oceans. The largest seas are located in the northern part: the Mediterranean - the Red Sea and the Persian Gulf, the semi-enclosed Andaman Sea and the marginal Arabian Sea; in the eastern part - the Arafura and Timor seas.

There are relatively few islands. The largest of them are of continental origin and are located near the coast: Madagascar, Sri Lanka, Socotra. In the open part of the ocean, there are volcanic islands - Mascarene, Crozet, Prince Edward, etc. In tropical latitudes, coral islands rise on volcanic cones - Maldives, Laccadive, Chagos, Cocos, most of the Andaman, etc.

Shores in the N.-W. and the East are indigenous, in the S.-V. and the West are dominated by alluvial. The coastline is slightly indented, with the exception of the northern part of the Indian Ocean. Almost all the seas and large bays (Aden, Oman, Bengal) are located here. In the southern part there are the Gulf of Carpentaria, the Great Australian Gulf and the gulfs of Spencer, St. Vincent, etc.

A narrow (up to 100 km) continental shelf (shelf) stretches along the coast, the outer edge of which has a depth of 50-200 m (only near Antarctica and northwestern Australia up to 300-500 m). The continental slope is a steep (up to 10-30°) ledge, locally dissected by the underwater valleys of the Indus, Ganges, and other rivers. m). The bed of the Indian Ocean is divided by ridges, mountains and ramparts into a number of basins, the most significant of which are the Arabian Basin, the West Australian Basin, and the African-Antarctic Basin. The bottom of these basins is formed by accumulative and hilly plains; the first are located near the continents in areas with an abundant supply of sedimentary material, the second - in the central part of the ocean. Among the numerous ridges of the bed, the straightness and length (about 5,000 km) distinguish the meridional East Indian Ridge, which connects in the south with the latitudinal West Australian Ridge; large meridional ridges stretch to the south from the Hindustan peninsula and about. Madagascar. Volcanoes are widely represented on the ocean floor (Mt. Bardina, Mt. Shcherbakov, Mt. Lena, and others), which in places form large massifs (to the north of Madagascar) and chains (to the east of the Cocos Islands). The mid-ocean ridges are a mountain system consisting of three branches that radiate from the central part of the ocean to the north (Arabian-Indian ridge), southwest. (West Indian and African-Antarctic ridges) and Yu.-V. (Central Indian Ridge and Australo-Antarctic Rise). This system has a width of 400–800 km, a height of 2–3 km, and is most dissected by an axial (rift) zone with deep valleys and rift mountains bordering them; transverse faults are characteristic, along which horizontal displacements of the bottom up to 400 km are noted. The Australo-Antarctic Rise, in contrast to the median ridges, is a gentler swell 1 km high and up to 1500 km wide.

The bottom sediments of the Indian Ocean are thickest (up to 3-4 km) at the foot of the continental slopes; in the middle of the ocean - small (about 100 m) thickness and in places where the dissected relief is distributed - discontinuous distribution. The most widely represented are foraminiferal (on continental slopes, ridges, and at the bottom of most basins at depths up to 4700 m), diatoms (south of 50° S), radiolarian (near the equator), and coral sediments. Polygenic sediments - red deep-sea clays - are distributed south of the equator at a depth of 4.5-6 km or more. Terrigenous sediments - off the coast of the continents. Chemogenic sediments are mainly represented by iron-manganese nodules, while riftogenic sediments are represented by destruction products of deep rocks. Outcrops of bedrocks are most often found on continental slopes (sedimentary and metamorphic rocks), mountains (basalts) and mid-ocean ridges, where, in addition to basalts, serpentinites and peridotites have been found, representing a slightly altered substance of the Earth's upper mantle.

The Indian Ocean is characterized by the predominance of stable tectonic structures both on the bed (thalassocratons) and along the periphery (continental platforms); active developing structures - modern geosynclines (Sonda arc) and georiftogenals (mid-ocean ridge) - occupy smaller areas and continue in the corresponding structures of Indochina and rifts of East Africa. These main macrostructures, which differ sharply in morphology, the structure of the earth's crust, seismic activity, and volcanism, are subdivided into smaller structures: plates, usually corresponding to the bottom of oceanic basins, blocky ridges, volcanic ridges, sometimes topped with coral islands and banks (Chagos, Maldives, etc.). .), trench-faults (Chagos, Ob, etc.), often confined to the foot of blocky ridges (East Indian, West Australian, Maldives, etc.), fault zones, tectonic ledges. Among the structures of the Indian Ocean bed, a special place (according to the presence of continental rocks - granites of the Seychelles and the continental type of the earth's crust) is occupied by the northern part of the Mascarene Range - a structure that is apparently part of the ancient Gondwana mainland.

Minerals: on the shelves - oil and gas (especially the Persian Gulf), monazite sands (the coastal region of Southwestern India), etc.; in rift zones - ores of chromium, iron, manganese, copper, etc.; on the bed - huge accumulations of iron-manganese nodules.

The climate of the northern part of the Indian Ocean is monsoonal; in summer, when an area of ​​low pressure develops over Asia, southwestern flows of equatorial air dominate here, in winter - northeastern flows of tropical air. South of 8-10 ° S sh. atmospheric circulation is much more constant; here, in tropical (summer and subtropical) latitudes, stable southeasterly trade winds dominate, and in temperate latitudes, extratropical cyclones moving from West to East. In tropical latitudes in the western part, hurricanes occur in summer and autumn. average temperature air in the northern part of the ocean in summer is 25-27 ° C, off the coast of Africa - up to 23 ° C. In the southern part, it decreases in summer to 20-25 ° C at 30 ° S. sh., up to 5-6 ° С at 50 ° S. sh. and below 0 ° С south of 60 ° S. sh. In winter, the air temperature varies from 27.5 °C near the equator to 20 °C in the northern part, to 15 °C at 30 ° S. sh., up to 0-5 ° С at 50 ° S. sh. and below 0 ° С south of 55-60 ° S. sh. At the same time, in the southern subtropical latitudes, the temperature in the West all year round under the influence of the warm Madagascar current is 3-6 °C higher than in the East, where the cold West Australian current exists. Cloudiness in the monsoon northern part of the Indian Ocean in winter is 10-30%, in summer up to 60-70%. In summer, there is also the greatest amount of precipitation. The average annual precipitation in the east of the Arabian Sea and the Bay of Bengal is more than 3000 mm, near the equator 2000-3000 mm, in the west of the Arabian Sea up to 100 mm. In the southern part of the ocean, the average annual cloudiness is 40-50%, south of 40 ° S. sh. - up to 80%. The average annual precipitation in the subtropics is 500 mm to the east and 1,000 mm to the west; in temperate latitudes, more than 1,000 mm; near Antarctica, it drops to 250 mm.

The circulation of surface waters in the northern part of the Indian Ocean has a monsoonal character: in summer - the northeast and east currents, in winter - the southwest and west currents. During the winter months between 3° and 8° S. sh. an inter-trade (equatorial) countercurrent develops. In the southern part of the Indian Ocean, water circulation forms an anticyclonic circulation, which is formed from warm currents - the South Trade Winds in the north, Madagascar and Needles in the West, and cold currents - the West Winds in the South and the West Australian in the East South of 55 ° S. sh. several weak cyclonic water cycles develop, closing off the coast of Antarctica with an easterly current.

The heat balance is dominated by a positive component: between 10° and 20° N. sh. 3.7-6.5 GJ/(m2×year); between 0° and 10°S sh. 1.0-1.8 GJ/(m2×year); between 30° and 40°S sh. - 0.67-0.38 GJ/(m2×year) [from - 16 to 9 kcal/(cm2×year)]; between 40° and 50°S sh. 2.34-3.3 GJ/(m2×year); south of 50°S sh. -1.0 to -3.6 GJ/(m2×yr) [-24 to -86 kcal/(cm2×yr)]. In the expenditure side heat balance north of 50°S sh. the main role belongs to the cost of heat for evaporation, and south of 50 ° S. sh. - heat exchange between the ocean and the atmosphere.

The surface water temperature reaches its maximum (over 29 °C) in May in the northern part of the ocean. In the summer of the Northern Hemisphere, it is 27-28 ° C here, and only off the coast of Africa decreases to 22-23 ° C under the influence of cold waters coming to the surface from the depths. At the equator, the temperature is 26-28 ° C and decreases to 16-20 ° C at 30 ° S. sh., up to 3-5 ° С at 50 ° S. sh. and below -1 ° С south of 55 ° S. sh. In the winter of the Northern Hemisphere, the temperature in the north is 23–25°C, at the equator 28°C, and at 30°S. sh. 21-25 ° С, at 50 ° S sh. from 5 to 9 ° С, south of 60 ° S sh. temperatures are negative. In subtropical latitudes all year round in the West, the water temperature is 3-5 °C higher than in the East.

The salinity of water depends on the water balance, which is formed on average for the surface of the Indian Ocean from evaporation (-1380 mm/year), precipitation (1000 mm/year) and continental runoff (70 cm/year). Main stock fresh water give the rivers of South Asia (Ganges, Brahmaputra, etc.) and Africa (Zambezi, Limpopo). The highest salinity is observed in the Persian Gulf (37-39‰), in the Red Sea (41‰) and in the Arabian Sea (more than 36.5‰). In the Bay of Bengal and the Andaman Sea, it decreases to 32.0-33.0‰, in the southern tropics - to 34.0-34.5‰. In the southern subtropical latitudes, salinity exceeds 35.5‰ (maximum 36.5‰ in summer, 36.0‰ in winter), and south of 40°S. sh. drops to 33.0-34.3‰. The highest water density (1027) is observed in the Antarctic latitudes, the lowest (1018, 1022) - in the northeastern part of the ocean and in the Bay of Bengal. In the northwestern part of the Indian Ocean, the density of water is 1024-1024.5. The oxygen content in the surface water layer increases from 4.5 ml/l in the northern part of the Indian Ocean to 7-8 ml/l south of 50°S. sh. At depths of 200-400 m, the oxygen content is much lower in absolute value and varies from 0.21-0.76 in the north to 2-4 ml / l in the south, at greater depths it gradually increases again and in the bottom layer is 4.03 -4.68 ml/l. The color of the water is predominantly blue, in the Antarctic latitudes it is blue, in some places with greenish hues.

The tides in the Indian Ocean, as a rule, are small (off the coast of the open ocean and on the islands from 0.5 to 1.6 m), only at the tops of some bays they reach 5-7 m; in the Gulf of Cambay 11.9 m. The tides are predominantly semi-diurnal.

Ice forms at high latitudes and is carried by winds and currents along with icebergs in a northerly direction (up to 55°S in August and up to 65-68°S in February).

The deep circulation and vertical structure of the Indian Ocean is shaped by waters sinking into the subtropical (subsurface waters) and Antarctic (intermediate waters) convergence zones and along the continental slope of Antarctica (bottom waters), as well as from the Red Sea and the Atlantic Ocean (deep waters). Subsurface waters have a temperature of 10-18°C at a depth of 100-150 m to 400-500 m, salinity of 35.0-35.7‰, intermediate waters occupy a depth of 400-500 m to 1000-1500 m, have a temperature of 4 to 10°C, salinity 34.2-34.6‰; deep waters at a depth of 1000-1500 m to 3500 m have a temperature of 1.6 to 2.8 ° C, salinity of 34.68-34.78‰; bottom waters below 3500 m in the south have a temperature of -0.07 to -0.24 ° C, salinity 34.67-34.69 ‰, in the north - about 0.5 ° C and 34.69-34.77 ‰ respectively.

Flora and fauna

The entire water area of ​​the Indian Ocean lies within the tropical and southern temperate zones. The shallow waters of the tropical zone are characterized by numerous 6- and 8-ray corals, hydrocorals, capable of creating islands and atolls together with calcareous red algae. The richest fauna of various invertebrates (sponges, worms, crabs, mollusks, sea urchins, brittle stars and starfish), small but brightly colored coral fish live among the powerful coral structures. Most of the coasts are occupied by mangroves, in which the mudskipper stands out - a fish capable of long time exist in the air. The fauna and flora of the beaches and rocks that dry out at low tide are quantitatively depleted as a result of the depressing effect of the sun's rays. In the temperate zone, life on such stretches of coasts is much richer; dense thickets of red and brown algae (kelp, fucus, reaching the enormous size of macrocystis) develop here, various invertebrates are abundant. For the open spaces of the Indian Ocean, especially for the surface layer of the water column (up to 100 m), rich flora is also characteristic. Of the unicellular planktonic algae, several species of peredinium and diatom algae predominate, and in the Arabian Sea - blue-green algae, which often cause the so-called water bloom during mass development.

Copepods (more than 100 species) make up the bulk of the ocean's animals, followed by pteropods, jellyfish, siphonophores, and other invertebrates. Of the unicellular, radiolarians are characteristic; numerous squids. Of the fish, the most abundant are several species of flying fish, luminous anchovies - myctophids, dolphins, large and small tuna, sailfish and various sharks, poisonous sea snakes. Sea turtles and large marine mammals (dugongs, toothed and toothless whales, pinnipeds) are common. Among the birds, the most characteristic are albatrosses and frigates, as well as several species of penguins that inhabit the coasts of South Africa, Antarctica and the islands that lie in the temperate zone of the ocean.