How many oceans are there on Earth: debate about the exact number. A short course in oceanography: how many oceans are there on Earth and what are their names

Our planet Earth is 70% water. Most of the water resources are 4 oceans. We will describe the existing oceans, their location, underwater inhabitants and interesting information.

1) Pacific Ocean

The Pacific Ocean is the most significant ocean in terms of area and depth. Its size is 169.2 million sq. km. Maximum depth – 11022 meters. Despite the name, he is considered the most violent, since... 80% of tsunamis originate here due to the many underwater volcanoes. The commercial importance of the ocean is significant - more than half of the world's fish catch is caught in the Pacific Ocean. In addition, 40% of oil and gas reserves are in the ocean. The Pacific Ocean contains over 950 varieties of algae, as well as over 120 thousand representatives of the animal world.

Interesting information:

• There are about 25 thousand in the Pacific Ocean. islands
• On one of the islands of the ocean they found very interesting objects of monetary settlement - stone rings more than two meters high and weighing 15 tons.
• This ocean has the highest waves, which is very popular among surfers
• Ocean water is capable of enveloping the entire surface of the Earth and the thickness of the water cover will exceed 2500 meters.
• The average speed of crushing waves during a tsunami is 750 km/h
• If all the water in the ocean suddenly evaporated, a layer of salt 65 meters thick would remain at the bottom.

2) Atlantic Ocean

The Atlantic Ocean is the next largest ocean on the planet. Its dimensions reach 91.6 million sq. km. The maximum depth reaches 8742 meters. All climate zones exist over the expanses of the Atlantic Ocean. The ocean provides two-fifths of the world's fish catch. It is enriched in mineral resources - there is oil, gas, iron ore, barite, limestone. The inhabitants of the ocean are very diverse - whales, fur seals, seals, sea urchins, parrot fish, sharks, surgeon fish, etc. There are many dolphins living in the ocean.

Interesting information:

• The warm Gulf Stream flows through the Atlantic Ocean, giving a warm climate to European countries with access to the ocean.
• Among the inhabitants, a special place is occupied by delicacies: oysters, mussels, squid, cuttlefish, etc.
• In the ocean there is a sea without shore boundaries - Sargasso.
• In the Atlantic there is a mystery of humanity - the Bermuda Triangle. This is an area in the Bermuda region where a large number of aircraft and ships have gone missing.
• The ocean also became famous for the sinking of the ship, the Titanic. Research at the bottom continues to this day.

3) Indian Ocean

The Indian Ocean is the 3rd largest ocean on the planet. Its dimensions reach 73.55 million sq. km. Maximum depth 7725 meters. It is considered the warmest and youngest ocean. Very numerous Tuna and various types of sharks are undoubtedly considered inhabitants of the ocean. IN smaller quantity Several different species of sea turtles, sea snakes, whales, sperm whales, and dolphins are present. The flora is represented mainly by brown and green algae. Mineral resources include natural gas, oil, rutile, titanite, zirconium, and phosphorite. Pearls and mother-of-pearl are mined from the ocean. Fishing reaches five percent of the world catch.

Interesting information:

1. In the Indian Ocean there are the most popular holiday islands such as Sri Lanka, Bali, Mauritius, and the Maldives.
2. The ocean contains the second most salinity sea on Earth - the Red Sea. The sea has completely clear water, since no rivers flow into it.
3. The largest sea corals are found at the bottom.
4. The most dangerous poisoner lives here - blue-ringed octopus . Its size is barely the size of a golf ball, and the poison kills in less than two hours.
5. One of the main mysteries of the ocean is the disappearance of people. Floating ships were repeatedly found without the slightest damage, but not a single person was present on it.

4) Arctic Ocean

The Arctic Ocean is the smallest ocean on Earth. Its dimensions are 14.75 million sq. km. Maximum depth 5527 meters. Ocean fauna is sparse due to the harsh climate. Among the fish, commercial fish such as herring, salmon, cod, and flounder predominate. Walruses and whales are found in large numbers.

Interesting Facts :

1. The phenomenon of “dead water” - due to the occurrence of internal waves, the ship stops, despite the fact that all engines are functioning.
2. The iceberg that destroyed the Titanic sailed from the Arctic Ocean.
3. The largest species of seal lives in the Arctic, weighing approximately 200 kilograms.
4. The most polluted ocean. There are a considerable number of bottles and bags at the bottom and on the surface.
5. Based on the melting of ice throughout the year, the salinity of the ocean can vary.

In 2000 International hydrographic The organization decided to identify the 5th ocean washing Antarctica - the Southern Ocean. But already in 2010 it was decided to remove the 5th ocean and leave 4.

The origin of the oceans on Earth is still unknown. However, we know that salt water covers approximately 360 million square kilometers of our planet. It is divided into several main oceans and smaller seas.

Oceans cover approximately 71% of the Earth's surface and 90% of its biosphere. They contain 97% of the Earth's water, and oceanographers say that only 5% of the ocean depths have been explored.

The world's oceans are a major component of the Earth's hydrosphere, making them an integral part of life, forming part of the carbon cycle, and influencing climate and weather patterns globally. The ocean is home to 230,000 known animal species, and possibly more than two million underwater species, as most are unexplored.

I wonder, actually, how many oceans there are in the world? For many years, only 4 were officially recognized, but in the spring of 2000, the International Hydrographic Organization established the Southern Ocean and defined its boundaries.

Oceans (from the ancient Greek Ὠκεανός, Okeanos) make up most of the planet's hydrosphere. In descending order by area, there are:

1. Quiet.
2. Atlantic.
3. Indian.
4. Southern (Antarctic).
5. Arctic oceans (Arctic).

Global ocean on Earth

Although several separate oceans are usually described, the global, interconnected body of salt water is sometimes called the World Ocean. The concept of a continuous body of water with relatively free exchange between its parts is of fundamental importance to oceanography.

The major oceanic spaces, listed below in descending order of area and volume, are defined in part by continents, various archipelagos, and other criteria.

Oceans, what they exist, their location

Quiet, the largest, extends north from the Southern Ocean to the Northern Ocean. It spans the gap between Australia, Asia and the Americas and meets the Atlantic south of South America at Cape Horn. Quiet - separates Asia and Oceania from North and South America. Area 168,723,000 km².

Atlantic, the second largest, stretches from the Southern Ocean between America, Africa and Europe to the Arctic. It meets the Indian Ocean waters south of Africa at Cape Agulhas. Atlantic - separates America from Europe and Africa. Area 85,133,000 km².

Indian, the third largest, extends north from the Southern Ocean to India, between Africa and Australia. It flows into the Pacific Ocean in the east, near Australia. Indian - borders southern Asia and separates Africa and Australia. Area 70,560,000 km².

Arctic the ocean is the smallest of the five. It joins the Atlantic near Greenland and Iceland and the Pacific Ocean in the Bering Strait and overlaps the North Pole, touching North America in the Western Hemisphere, Scandinavia and Siberia in the Eastern Hemisphere. Almost all covered sea ​​ice, the area of ​​which varies depending on the season. Arctic - covers most of the Arctic and washes North America and Eurasia. Area 15,000 km². They are bordered by small adjacent bodies of water, such as seas, bays and straits.

Southern- surrounds Antarctica, where the Antarctic Circumpolar Current predominates. This maritime space only recently recognized as a separate oceanic unit, which lies south of sixty degrees south latitude and is partially covered by sea ice, the extent of which varies with the season. Southern - sometimes seen as the extension of the Pacific, Atlantic and Indian Oceans that surround Antarctica. Area 21,000 km².

Physical properties

1. The total mass of the hydrosphere is about 1.4 quintillion metric tons, which is about 0.023% of the Earth's total mass. Less than 3% – fresh water; the rest is salt water.
2. The ocean area is about 361.9 million square kilometers and covers about 70.9% of the Earth's surface, and the volume of water is about 1.335 billion cubic kilometers.
3. The average depth is about 3,688 meters and the maximum depth is 10,994 meters in the Mariana Trench. Almost half of the world's sea waters have a depth of more than 3 thousand meters. Vast areas below 200 meters depth cover about 66% of the Earth's surface.
4. The bluish color of the water is integral part several contributing agents. Among them are dissolved organic matter and chlorophyll. Sailors and other sailors have reported that ocean waters often emit a visible glow that extends for many miles at night.

Oceanic zones

Oceanographers divide the ocean into different vertical zones determined by physical and biological conditions. The pelagic zone includes all zones and can be divided into other areas, divided by depth and illumination.

The photic zone includes surfaces up to a depth of 200 m; it is an area where photosynthesis occurs and therefore has great biological diversity.

Because plants require photosynthesis, life found deeper than the photonic zone must either rely on material falling from above or find another source of energy. Hydrothermal ventilation holes are the main source of energy in the so-called aphotic zone (depths greater than 200 m). The pelagic part of the photonic zone is known as epipelagic.

Climate

Cold deep water rises and warms in the equatorial zone, while thermal water sinks and cools near Greenland in the North Atlantic and near Antarctica in the South Atlantic.

Ocean currents greatly influence the Earth's climate by transporting heat from the tropics to the polar regions. By transferring warm or cold air and precipitation to coastal areas, winds can carry them inland.

Many of the world's goods move by ship between the world's seaports. Ocean waters are also the main source of raw materials for the fishing industry.

However, just recently...

... in 2000, the International Hydrographic Organization combined the southern Atlantic, Indian and Pacific oceans, creating a fifth addition to the list - the Southern Ocean. And this is not a volitional decision: this region has a special structure of currents, its own rules of weather formation, etc. The arguments in favor of such a decision are as follows: in the southern part of the Atlantic, Indian and Pacific oceans, the boundaries between them are very arbitrary, while at the same time the waters adjacent to Antarctica, have their own specifics, and are also united by the Antarctic Circumpolar Current.

The largest of the oceans is the Pacific. Its area is 178.7 million km2. .

The Atlantic Ocean extends over 91.6 million km 2.

The area of ​​the Indian Ocean is 76.2 million km2.

The area of ​​the Antarctic (Southern) Ocean is 20.327 million km 2.

The Arctic Ocean covers an area of ​​approximately 14.75 million km2.

Pacific Ocean , the largest on Earth. It was named so by the famous navigator Magellan. This traveler was the first European to successfully cross the ocean. But Magellan was just very lucky. There are very often terrible storms here.

The Pacific Ocean is twice the size of the Atlantic. It occupies 165 million square meters. km, which is almost half the area of ​​the entire World Ocean. It contains more than half of all the water on our planet. In one place, this ocean extends 17 thousand km in width, stretching almost half the globe. Despite its name, this huge ocean is not only blue, beautiful and serene. Strong storms or underwater earthquakes make him furious. In fact, the Pacific Ocean is home to large zones of seismic activity.

Photographs of the Earth from space show the true size of the Pacific Ocean. This is the largest ocean in the world, covering one third of the planet's surface. Its waters stretch from East Asia and Africa to the Americas. At its shallowest points, the depth of the Pacific Ocean averages 120 meters. These waters wash the so-called continental shelves, which are submerged parts of continental platforms, starting from the coastline and gradually going under water. Overall, the depth of the Pacific Ocean averages 4,000 meters. The depressions in the west connect into the deepest and darkest place in the world - the Mariana Trench - 11,022 m. It was previously believed that there was no life at such depths. But scientists found living organisms there too!

On the Pacific Plate, a huge area earth's crust, there are ridges of high seamounts. In the Pacific Ocean there are many islands of volcanic origin, for example Hawaii, the largest island of the Hawaiian Islands archipelago. Hawaii is home to the highest peak in the world, Mauna Kea. It is an extinct volcano 10,000 meters high from its base on the seabed. In contrast to volcanic islands, there are low-lying islands formed by coral deposits that have been deposited over thousands of years on the tops of underwater volcanoes. This vast ocean is home to a wide variety of underwater species - from the world's largest fish (whale shark) to flying fish, squid and sea lions. The warm, shallow waters of coral reefs are home to thousands of species of brightly colored fish and algae. All kinds of fish, marine mammals, mollusks, crustaceans and other creatures swim in the cool, deep waters.

Pacific Ocean - people and history

Sea voyages across the Pacific Ocean have been undertaken since ancient times. About 40,000 years ago, Aboriginal people crossed by canoe from New Guinea to Australia. Centuries later between the 16th century BC. e. and X century AD e. Polynesian tribes settled the Pacific islands, venturing across vast distances of water. This is considered one of the greatest achievements in the history of navigation. Using special canoes with a double bottom and sails woven from leaves, Polynesian sailors ultimately covered almost 20 million square meters. km of ocean space. In the western Pacific, around the 12th century, the Chinese made great advances in the art of sea navigation. They were the first to use large ships with multiple underwater masts, steering, and compasses.

Europeans began exploring the Pacific Ocean in the 17th century, when the Dutch captain Abel Janszoon Tasman sailed around Australia and New Zealand. Captain James Cook is considered one of the most famous explorers of the Pacific Ocean. Between 1768 and 1779 he mapped New Zealand, the east coast of Australia and many of the Pacific islands. In 1947, the Norwegian explorer Thor Heyerdahl sailed on his raft “Kon-Tiki” from the coast of Peru to the Tuamotu archipelago, part of French Polynesia. His expedition provided evidence that the ancient indigenous inhabitants of South America could cross vast sea distances on rafts.

In the twentieth century, exploration of the Pacific Ocean continued. The depth of the Mariana Trench was established, and unknown species of marine animals and plants were discovered. Development of the tourism industry, pollution environment and beach development threaten the natural balance of the Pacific Ocean. Governments of individual countries and groups of environmentalists are trying to minimize the harm caused by our civilization to the aquatic environment.

Indian Ocean

Indian Ocean is the third largest on Earth and covers 73 million square meters. km. This is the warmest ocean, the waters of which are rich in various flora and fauna. The deepest place in the Indian Ocean is a trench located south of the island of Java. Its depth is 7450 m. Interestingly, currents in the Indian Ocean change their direction to the opposite direction twice a year. IN winter time When the monsoons prevail, the current goes to the shores of Africa, and in the summer - to the shores of India.

The Indian Ocean stretches from the coast of East Africa to Indonesia and Australia and from the coast of India to Antarctica. This ocean includes the Arabian and Red Seas, as well as the Bays of Bengal and the Persian Gulf. The Suez Canal connects the northern part of the Red Sea with the Mediterranean.

At the bottom of the Indian Ocean there are huge sections of the earth's crust - the African Plate, the Antarctic Plate and the Indo-Australian Plate. Shifts in the earth's crust cause underwater earthquakes, which cause giant waves called tsunamis. As a result of earthquakes, new mountain ranges appear on the ocean floor. In some places, seamounts protrude above the surface of the water, forming most of the islands scattered in the Indian Ocean. There are deep depressions between the mountain ranges. For example, the depth of the Sunda Trench is approximately 7450 meters. The waters of the Indian Ocean are home to a variety of wildlife, including corals, sharks, whales, turtles and jellyfish. Powerful currents are huge streams of water moving through the warm blue expanses of the Indian Ocean. The Western Australian Current carries cold Antarctic waters north to the tropics.

The equatorial current, located below the equator, circulates warm waters counterclock-wise. Northern currents depend on the monsoon winds that cause heavy rainfall, which change their direction depending on the time of year.

Indian Ocean - people and history

Sailors and traders plied the waters of the Indian Ocean many centuries ago. Ships of the ancient Egyptians, Phoenicians, Persians and Indians passed along the main trade routes. In the early Middle Ages, settlers from India and Sri Lanka crossed into Southeast Asia. Since ancient times, wooden ships called dhows sailed the Arabian Sea, carrying exotic spices, African ivory and textiles.

In the 15th century, the great Chinese navigator Zhen Ho led a large expedition across the Indian Ocean to the shores of India, Sri Lanka, Persia, the Arabian Peninsula and Africa. In 1497, the Portuguese navigator Vasco da Gama became the first European whose ship sailed around the southern tip of Africa and reached the shores of India. English, French and Dutch traders followed, and the era of colonial conquest began. Over the centuries, new settlers, traders and pirates have landed on the islands in the Indian Ocean. Many species of island animals that lived nowhere else in the world became extinct. For example, the dodo, a goose-sized flightless pigeon native to Mauritius, was exterminated by the end of the 17th century. Giant turtles on Rodrigues Island have disappeared 19th century. Exploration of the Indian Ocean continued in the 19th and 20th centuries. Scientists have done a great job mapping the topography of the seabed. Currently, Earth satellites launched into orbit take pictures of the ocean, measure its depth and transmit information messages.

Atlantic Ocean

Atlantic Ocean is the second largest and covers an area of ​​82 million square meters. km. It is almost half the size of the Pacific Ocean, but its size is constantly increasing. From the island of Iceland to the south in the middle of the ocean a powerful underwater ridge stretches. Its peaks are the Azores and Ascension Island. The Mid-Atlantic Ridge, a large mountain range on the ocean floor, is becoming wider each year by about an inch. The deepest part of the Atlantic Ocean is a trench located north of the island of Puerto Rico. Its depth is 9218 meters. If 150 million years ago there was no Atlantic Ocean, then over the next 150 million years, scientists suggest, it will begin to occupy more than half of the globe. The Atlantic Ocean greatly influences the climate and weather in Europe.

The Atlantic Ocean began to form 150 million years ago, when shifts in the Earth's crust separated North and South America from Europe and Africa. This youngest of the oceans is named after the god Atlas, who was worshiped by the ancient Greeks.

Ancient peoples, such as the Phoenicians, began exploring the Atlantic Ocean around the 8th century BC. e. However, only in the 9th century AD. e. The Vikings managed to reach from the shores of Europe to Greenland and North America. The “golden age” of Atlantic exploration began with Christopher Columbus, an Italian navigator who served the Spanish monarchs. In 1492, his small squadron of three ships entered the Caribbean Gulf after a long storm. Columbus believed that he was sailing to the East Indies, but in fact he discovered the so-called New World - America. He was soon followed by other sailors from Portugal, Spain, France and England. The study of the Atlantic Ocean continues to this day. Currently, scientists use echolocation (sound waves) to map the topography of the seabed. Many countries fish in the Atlantic Ocean. People have fished these waters for thousands of years, but modern fishing by trawlers has led to a significant reduction in fishing schools. The seas surrounding the oceans are polluted with waste. The Atlantic Ocean continues to play a huge role in international trade. Many important trade sea routes pass through it.

Arctic Ocean

Arctic Ocean, which is located between Canada and Siberia, is the smallest and shallowest compared to the others. But it is also the most mysterious, since it is almost completely hidden under a huge layer of ice. The Arctic Ocean is divided into two basins by the Nansen Threshold. The Arctic basin is larger in area and contains the greatest ocean depth. It is equal to 5000 m and is located north of Franz Josef Land. In addition, here, off the Russian coast, there is an extensive continental shelf. For this reason, our Arctic seas, namely: Kara, Barents, Laptev, Chukotka, East Siberian, are shallow.