home Educational literature What is the importance of the oceans in the life of the planet. Importance of oceans and seas in human life. What is sea water made of?

What is the importance of the oceans in the life of the planet. Importance of oceans and seas in human life. What is sea water made of?

There is a fair assertion that people incorrectly named our planet, giving it the name Earth, while it should have been called the Ocean, since more than 70 percent of its area is occupied by water. In all solar system only the Earth has a sufficient volume of water and thermal conditions, which, combined, ensure the existence of a vast World Ocean.

The aquatic environment - the hydrosphere - occupies a significant part biosphere- areas of life, consisting of land, air and water. The main part of the hydrosphere is the ocean. Water and substances dissolved in it are found in the seas, rivers, lakes and glaciers, and are also hidden at different depths underground.

A diver explores the continental rift in Silfra, Iceland, 2010.
The photograph won the highest award in the category "Diving" in the fourth international competition underwater photography in Indonesia.

The role of the World Ocean in the life of the Earth is difficult to overestimate. The ocean is the cradle and source of life on our planet. More than half of the oxygen needed for breathing comes from photosynthesis in the upper layer of ocean waters. If the interaction of the ocean and the sun were suddenly interrupted, all life on Earth would cease.

The ocean is a heat accumulator, creator and regulator of climate. Its role in maintaining the constancy of the climate is enormous. It is the interaction of the World Ocean and the atmosphere that determines the weather on our planet.

The ocean is a convenient and cheap road that connects continents and islands, industrial centers, agricultural regions, and sources of raw materials. Tens of thousands of ships carry out sea transportation of passengers and all kinds of cargo, annually transporting hundreds of millions of tons of cargo.

The ocean is an inexhaustible treasure trove of chemicals. Almost all the elements of the Periodic Table of Mendeleev are dissolved only in sea water. It has literally everything from table salt to uranium and gold. Innumerable riches hide the bottom of the oceans. Coal, iron ore, tin, sulfur are extracted from the primary deposits of the seabed. Placer deposits of tin, platinum, rare earth elements are already being developed in the beach and coastal zones. Serious attention is paid to the development of deep-water ore deposits. Large deposits of phosphorites are located on the shelf and continental slope of the World Ocean. The vast bottom plains of the ocean are covered with ferromanganese nodules, in the development of which the first steps are already being taken. Mining in full swing building materials- sand, gravel, shell rock.

The most valuable mineral raw materials currently mined from wells at the bottom of the seas are undoubtedly oil and gas. To date, the world's offshore oil production has amounted to 30 percent.

And finally, the ocean is an inexhaustible source of renewable energy. This and the reserves contained in the water heavy hydrogen- deuterium - the thermonuclear fuel of the future, and the energy of sea waves, currents, tides, the temperature difference between deep and surface waters ...

From time immemorial, the ocean served as a source of food for man, who obtained fish, crustaceans, molluscs, marine animals and plants in it. Throughout the centuries-old history of mankind, the methods and tools of coastal fishing have not changed much. Oceanic fisheries, which fish far from the coast, have undergone tremendous changes. Especially in recent decades. A real revolution in the development of ocean fishing was made by the invention of the steam engine and the internal combustion engine, the use of synthetic materials for the manufacture of fishing gear, and the equipping of fishing vessels with fish-searching equipment. Modern trawls, purse seines, longlines are quite complex engineering structures that provide the possibility of catching a large amount of fish - up to several tens of tons per trawl!

For a long time there was an opinion about the inexhaustibility of the ocean's fish resources. This has been greatly facilitated by the rapid growth in global fish catches, especially in last years. If in a century, from 1850 to 1950, the catch of sea fish and other products of the ocean increased 10 times, increasing by an average of 25 percent per decade, then from 1950 to 1960 it doubled! The subsequent doubling of the world catch occurred from 1960 to 1970. World fish production by this time approached 100 million tons.

Already since 1970, the pace of the world catch of fish and seafood began to slow down, despite the ever-increasing intensity of fishing. In some traditional fishing areas, fish production began to decline, the species composition of catches changed, the average size of fish decreased, and some commercial species were threatened with extinction.

Thus, mankind was personally convinced of the limited fish resources of the seas and oceans.

Most scientists involved in determining the annual fish production of the ocean agree that it is 100 - 200 million tons. The annual fish catch achieved so far (about 100 million tons) is close to the amount that can be taken from the ocean without disturbing the natural reproduction process.

One of the most acute problems on Earth is the problem of providing the population of our planet with a sufficient amount of protein food, part of which a person takes in the ocean, catching marine animals. This problem is getting more greater value, if we take into account the natural increase in the population of our planet. Thus, according to scientists' forecasts, by the beginning of the third millennium the population of the Earth will approach 6 billion people. It is known that the physiological need of a person for fish is on average 20 kilograms per year.

How to ensure the natural reproduction of biological resources in the seas and oceans?

Some prospects for increasing fish catches are fresh waters, but they still provide only a tenth of the world's catch. The possibilities for expanding fisheries in the seas and oceans are much richer.

Great importance currently under development scientific methods fishing, taking into account the peculiarities of the biology of commercial fish species, the nature of their distribution, age composition, abundance and other indicators. Not the last word also belongs to the improvement of fishing gear, fish processing technology.

In this case, the development of new areas and objects of fishing is of particular importance. First of all, this applies to the fishing of the inhabitants of the upper layer of the ocean - the epipelagic zone, such as mackerel pike, flying fish, small tuna, squid. The fishery of small-sized fish is promising - luminous anchovies, gonostomas, living in the intermediate layer of ocean waters - mesopelagial. Significant progress has been made in the development of deep-water uplifts of the World Ocean with relatively large fishing depths - 800-1000 meters, where powerful accumulations of grenadier, doryfish, smooth-headed and other fish species have been found.

Critical to increasing the harvest of the biological resources of the oceans will belong to objects of a lower trophic level than fish, such as Antarctic krill, which is now fished by many countries.

Until now, speaking about the possibilities of increasing the catch of fish and seafood, we meant only the rational use of the natural food resources of the World Ocean, showing some ways to improve the traditional “gathering or hunting”, which until recently was, in fact, fishing. Scientists in many countries are working on how to move from "gathering and hunting" to marine management.

According to some scientists, the transition of the fishing industry from the extraction of fish to the breeding of marine plants and animals can cause changes in human civilization that are not inferior in importance to the emergence of Agriculture when man moved from "gathering and hunting" to cultivating the soil. Such a reorganization of the fish industry will be, in fact, a "blue revolution". The onset of such a revolution is not far off. Successful experiments on artificial breeding of fish have already been carried out. Work is underway to increase the biological productivity of sea waters by lifting deep, nutrient-rich layers to the surface. Creation of artificial reefs, development of new, more productive species plants and animals, the achievements of genetics and ethology, the science that studies the behavior of animals - these are the ways of continuous and human controlled the growth of the gifts of the ocean.

The future of mankind is closely connected with the use of the resources of the oceans. The growing demand for mineral raw materials, energy and food resources makes people more and more often turn their attention to the ocean. The problems of the development of the World Ocean are complex, closely interconnected and must be solved in a comprehensive manner, by the combined efforts of various specialists from all countries. The ocean belongs to everyone, and we are all responsible for its fate!

The oceans and life on earth

Now we already know what our Earth looks like from space - it is unusually beautiful blue planet. It owes its impressive coloration to the World Ocean, which covers 71% of its surface. The oceans are a powerful factor in life on Earth. It purifies the air, refreshes it with moist winds. Life was once born here, and now it supplies us with the most valuable products.

Without the oceans, life on land would be completely different. Marine plants, in particular phytoplankton, which release oxygen through photosynthesis, play an important role in purifying the air on our planet. The ability of water to store heat greatly affects the weather and climate of the Earth. In the marine food chain, a kind of cycle of terrestrial flora and fauna occurs: plant plankton, as the primary product of marine life, is eaten by the "vegetarians" of the ocean - zooplankton and mollusks, which, in turn, are eaten by small carnivores, such as anchovy or flounder, and those become the prey of larger marine predators. The remains of plant or animal food are returned to the chain in the form of organic matter through mineralization, thanks to the action of bacteroplankton.

The sea creates many factors that have a beneficial effect on the body. Of great importance is sea air, which has a uniform temperature, contains a large number of oxygen, enriched with such important mineral salts for the body as calcium, sodium, iodine, chlorine, etc. Thanks to this composition, sea air improves the activity of the cardiovascular, nervous systems and respiration of the body.

Sea water contains salts of sodium, magnesium, iron, iodine, chlorine, bromine, etc., including table salt.

The oceans are the main base for fishing. Sea spaces are used for the transportation of large cargoes and passengers. A variety of minerals (iron, manganese, gold, diamonds, titanium, chromium, etc.) are already being mined from the seabed, about 20% (on a global scale) of oil and gas production is carried out - for many countries Western Europe offshore fields are the main sources of oil.

The wide scope of the economic use of the seas by man is accompanied by their pollution. Seas and oceans until recently (20-30 years ago) were perceived as unlimited expanses into which you can release as much waste and garbage as you like. It was believed that discharges in sea water undergo biological decay and transformations. During this short period, significant amounts of radioactive waste and other pollution have been introduced into the oceans.

It is known that all discharges into rivers, lakes and other water bodies located on the territory of large industrial centers and agricultural areas eventually reach the sea. With the waters of rivers, 320 million tons of iron, 6.5 million tons of phosphorus, 2.3 million tons of lead, 1.6 million tons of manganese, as well as a large amount of fats, surfactants, acids, enter the seas and oceans , pesticides, radioactive compounds, from 3 to 10 million tons of oil and other substances. According to the calculations of the well-known oceanologist-geochemist B. A. Skopintsev, rivers bring about 700 million tons of organic matter per year to the seas and oceans. Most of all, those pollutions that have the property of retaining their toxic effect for a long time are washed into the seas.

Significant pollution in the seas is brought by various developments of minerals (oil and others), as well as maritime transport.

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instead of a preface.

In this section of the site, we aim to bring to our readers more detailed information about the World Ocean as the main part of the Earth's biosphere. The section "World Ocean" contains information about the origin and evolution of the World Ocean, its size and constituent parts, about the composition and properties of sea water, about the structural features of the ocean floor, about ocean currents, about life in the ocean, about the use of the wealth of the ocean. The reader will be able to be convinced of the great importance of the ocean for mankind, as well as that the ocean, like a living being, needs protection.

1. General Provisions. Origin of the ocean.

Earth is the only planet in the solar system that has a hydrosphere. The main and main part of the hydrosphere is the World Ocean. It is the ocean that gives the Earth its unique beauty and originality. Of course, being on the surface of the Earth, a person cannot see the globe from the side and appreciate its beauty. But it is known what delight seizes astronauts when they admire our planet from near space. Even the first cosmonaut of the Earth, Yuri Alekseevich Gagarin, who had very little time in flight, managed to see from orbit and appreciate the stunning beauty of our planet.

And this beauty is created to a certain extent by the boundless World Ocean, turning the Earth into a blue planet.

The ocean is huge. The area of the entire surface of the Earth is estimated at 510 million km 2, of which about 361 million km 2 (70.8%) is covered with water. But if we take into account the glaciers that cover 11% of the land, it turns out that not 361, but 380 million km 2, that is, 75% of its surface, are covered with water on Earth.

It is estimated that the amount of water in the ocean is approximately 1370 million km 3 . Interestingly, the volume of land rising above sea level is about 111 million cubic kilometers, that is, ten and a half times less than the volume of water.

About 4% of all water on the planet falls on the share of lakes, swamps, rivers, underground (more precisely, intra-ground) waters and the atmosphere, and the rest of the water fills a giant bowl called the World Ocean.

Where did such a huge amount of water come from on Earth? Scientists and thinkers have been looking for an answer to this question for centuries. It is now officially recognized in science Earth degassing hypothesis , according to which 4 billion years ago, after cooling earth's crust, through cracks in the crust and vents of volcanoes, the ejection of hot magma began with the simultaneous release of gases, water vapor and hot water to the surface. The start of the degassing process is considered the start geological history Earth and the beginning of the formation of its hydrosphere.

The time of the beginning of the process of degassing, which means the appearance of water on Earth, is indirectly confirmed, for example, by the fact that in the most ancient rocks of the earth's crust, whose age is determined at 3.8 billion years, imprints of unicellular organisms were found that could exist only if liquid water.

During the presumably first billion years of the planet's existence, the upper mantle was subjected to an active process of degassing, when water and acidic degassing products of mantle matter were carried to the Earth's surface. The volume of water coming from the bowels of the Earth increased from 0 to 1.3 km 3 per year. About 2.5 billion years ago, the average thickness of the water layer in the ocean probably did not exceed 2000 meters. Approximately 1.7 billion years ago, the chemical composition of oceanic waters and the earth's atmosphere became close to modern. The volume of water coming from the bowels of the Earth slowly decreased and is currently about 0.25 km 3 per year. This means that the process of degassing continues, which is confirmed by the still ongoing volcanic activity on Earth.

The hypothesis looks logical and quite scientific. In fact, it was not from outer space that water entered the ancient depressions of the earth's crust. And if later, with the advent of the atmosphere, water poured from the clouds, then it was still terrestrial in origin, since the clouds contained a condensate of water vapor coming out of the bowels of the Earth.

Some provisions of this hypothesis are questionable. For example, its authors (V.S. Safronov, O.G. Sorokhtin and others) believe that the heating of the interior of the young Earth occurred due to the fall of cosmic bodies onto its surface, and also partially due to the radioactive decay of the nuclei of heavy elements. It is difficult to argue about radioactive decay here, but what mass should the hypothetical cosmic bodies have in order for their impacts on the Earth's surface to heat up its bowels? On the other hand, why warm up the bowels if they were originally hot? But let's not get distracted by the specifics.

Oceanologists believe that The water cycle on Earth is not closed, since 0.25 km 3 of additional water annually flows from the bowels of the planet through rift cracks. Part of the water, rising in the form of vapors to the upper layers of the atmosphere, decomposes into hydrogen and oxygen under the influence of solar and cosmic radiation and goes into space.

The rift cracks just mentioned are fractures in the earth's crust that occur at the boundaries of the lithospheric plates in zones where the plates move away from each other. The process by which lithospheric plates move away from each other is called in geology spreading. A giant rift crack that appeared in the spreading zone, for example, crosses almost in the middle of the entire Atlantic Ocean in the meridian direction.

So, the ocean has existed throughout the earth's geological history . There are facts that prove this assertion. For example, in the south-west of Greenland in the 70s of the twentieth century, sedimentary brown ironstone was found, whose age is estimated at 3.76 billion years. This means that even then, in the epoch of the Catarchean, sedimentary rocks began to form as a result of the water cycle between the ocean, atmosphere and land.

Note: Catarchean is the geological epoch immediately following the pregeological era. The duration of the Katarchean is estimated at 800 million years (from 3500 to 2700 million years ago).

Russian volcanologists have calculated that during a volcanic eruption, the proportion of water vapor is about 3% of the mass of erupted substances. It turned out that this value almost exactly corresponds to the ratio between the masses of the modern hydrosphere (1.46 * 10 6) and the earth's crust (4.7 * 10 7). This is the second proof of the constant presence of the hydrosphere on the globe.

The third proof of the eternal and continuous existence of the ocean is the finds of the remains and imprints of the bodies of ancient living organisms. Thus, life on Earth has existed without interruption for a moment for three billion years, and its prosperity is provided by the ocean. Life originated in the ocean as a result of a long interaction of various substances dissolved in sea water. Now this hypothesis is almost universally accepted. Why almost? Because there must always be doubt. And when there is doubt, then there is a reason and a stimulus for further work of thought. But one thing is certain: evolution organic world is directly related to the emergence and development of the Earth's water shell. It should be noted that if life in the ocean originated three billion years ago, then it appeared on land only 600 million years ago.

The upper hundred-meter layer of ocean water contains a huge amount of photosynthetic single-celled algae. These tiny organisms, together with other plants living in the water, release oxygen and absorb oxygen dissolved in sea water. carbon dioxide. There is a constant exchange of gases between water and the atmosphere. It means that The ocean plays a vital role in the balance of oxygen and life on the entire planet..

It hardly needs to be proven the critical importance of the ocean as a source of food resources for humans. At present, due to the constant growth of the world's population and the often unreasonable, predatory use by man of the biological resources of the ocean, marine fishing has essentially reached its limit. The time has come when it is necessary not only to procure animals and plants in the seas, but also to breed and cultivate many of their species exactly as man has been forced to do on land for thousands of years.

The ocean stores a huge amount of salts and other minerals, necessary for a person . Under the bottom of the shelf and the ocean floor there are deposits of coal, oil and gas, the development of which has long been carried out in many countries.

The ocean can be seen as colossal energy storage which is still little used. Not much time will pass, even on the scale of human life, and the natural reserves of oil, gas, hard coal and radioactive ores run out. Then the ocean will become the main source of energy for industrial and domestic needs. True, extracting energy from the ocean will be much more difficult than simply burning gas, coal and oil products in furnaces.

If we talk about the meaning of the ocean as the main means of transport links between continents, it should be noted that no "road surfaces" or rails are required for laying sea lanes. All that is needed is reliable vehicles for the transport of people and goods and appropriate coastal infrastructure. And therein lies a certain economic advantage of sea routes over land routes. Another thing is that sea travel and cargo transportation are much more dangerous than land travel. But this forces scientists and designers to constantly improve the design and increase the reliability of ships not only for military, but also for national economic purposes.

Water is the most abundant substance on earth. The water shell of the Earth developed along with the lithosphere, atmosphere and wildlife. Almost all processes on our planet proceed with the participation of water. The hydrosphere consists of the oceans, land waters and groundwater. The bulk of the water is concentrated in the oceans.

The World Ocean is the blue mirror of our planet, the cradle of life on Earth. It contains not only the past, but also the future of our planet. To understand great role ocean, it is necessary to know the features of its nature: the properties of water masses, to understand the role of currents, the significance of the interaction of the ocean with the atmosphere and land. You will learn about all this by studying this topic.

§ 9. Waters of the oceans

What is called the hydrosphere? World Ocean?
What do you already know about the nature of the ocean?
Make a characterization of the map of the oceans (see the plan in the appendix).

The role of the ocean in the life of the Earth. The ocean occupies almost 3/4 of the surface of our planet (Fig. 22). Water is one of the most amazing substances on Earth, a precious liquid, a gift of nature to our planet. In such quantities as on Earth, it is not found anywhere in the solar system.

Rice. 22. The area of land and ocean: a) in general on Earth; b) in the Northern Hemisphere; c) in the southern hemisphere

The ocean... It is hard to imagine how great its importance in the life of the Earth. Clouds in the sky, rain and snow, rivers and lakes, springs - all these are particles of the ocean that have only temporarily left it.

The ocean determines many features of the nature of the Earth: it gives the atmosphere the accumulated heat, nourishes it with moisture, part of which is transferred to the land. He renders big influence on climate, soil, vegetation and animal world sushi. Its role in human economic activity is great. The ocean is a healer, giving medicines and taking millions of vacationers to its shores. He is a source of seafood, many minerals, energy; he is the "kitchen of the weather", and the most spacious road in the world connecting the continents. Thanks to the work of bacteria, the ocean has the ability (up to a certain limit) to self-clean, and therefore many of the waste generated on Earth is destroyed in it.

The history of mankind is inextricably linked with the study and development of the ocean. Its knowledge began in ancient times. (When? By whom?) Especially a lot of new data has been obtained over the past decades with the help of the latest technology. Research carried out on scientific vessels, collected by automatic oceanographic stations, as well as artificial satellites Earth, helped to detect eddies in the waters of the ocean, deep countercurrents, to prove the existence of life on great depths. The study of the structure of the ocean floor made it possible to create a theory of the movement of lithospheric plates.

Origin of the waters of the oceans. Ocean - chief keeper water, the most common substance on Earth, which has long amazed researchers with its unusual properties. Only water under normal terrestrial conditions can be in three states. This property ensures the omnipresence of water. It permeates the entire geographic shell and performs a variety of work in it.

How did water appear on Earth? Finally, this “survey” has not yet been resolved by science. It is assumed that water either released immediately during the formation of the lithosphere from the upper mantle, or accumulated gradually. Water is still released from magma, falling on the surface of the planet during volcanic eruptions, during the formation oceanic crust in zones of stretching of lithospheric plates. This will continue for many millions of years. Part of the water comes to Earth from space.

properties of ocean waters. Their most characteristic properties - salinity and temperature - are already known to you. (Recall their key metrics from grade 6.) Oceanic mode is a weak solution in which almost no chemical substances. Dissolved in it are gases, mineral and organic matter formed as a result of the life of organisms.

The main changes in salinity are observed in the surface layer. The salinity of waters depends mainly on the ratio of precipitation and evaporation, which varies depending on geographical latitude. At the equator, the salinity is about 34%.., near the tropics - 36%, and in temperate and polar latitudes - about 33%. Salinity is less where the amount of precipitation exceeds evaporation, where there is a large influx of river waters, where ice melts.

You know that the waters of the ocean are heated, like the land, from the influx of solar heat on its surface. Occupying a large area, the ocean receives more heat than land. The temperature of surface waters varies and is distributed depending on the latitude (Fig. 23). AT certain areas ocean, this pattern is violated by ocean currents, and in coastal parts - by the runoff of warmer waters from the continents. The temperature of the ocean water also changes with depth. At first, its decrease is very significant, and then it slows down. At depths of more than 3-4 thousand meters, the temperature usually ranges from +2 to 0 °C.

Rice. 23. The average annual water temperature on the surface of the oceans. Compare water temperatures at the same latitudes. Explain the result

Ice in the ocean. The formation of ice depends on the temperature of ocean waters. You already know that sea water freezes at -2 °C. As salt water cools, the density of salt water increases, its upper layer becomes heavier and sinks down, and warmer layers of water rise to the surface. This mixing of the water prevents the formation of ice. Ice forms only in arctic and subarctic latitudes, where winters are long and very cold. Some shallow seas located in the temperate zone also freeze. Distinguish between annuals and multi-year ice. Ocean ice can be immobile if it is connected to the land, or floating, i.e. drifting. In the ocean, there are ices that have broken off from the glaciers of the land and descended into the ocean - icebergs (Fig. 24).

Rice. 24. Melting icebergs in the ocean

The ice cover of the ocean has a huge impact on the climate of the Earth, on life in it. Ice reflect Sun rays, cool the air, contribute to the formation of fogs. They impede navigation and marine fisheries.

water masses. Water is the main component of the nature of the ocean. Large volumes of water that form in certain parts of the ocean and differ from each other in temperature, salinity, density, transparency, the amount of oxygen, the presence of certain living organisms, are called water masses. These properties are preserved throughout the space occupied by one or another water mass.

In the ocean, surface, intermediate, deep, and bottom water masses are distinguished. In surface fashionable masses up to a depth of 200 m, equatorial masses are distinguished. tropical, temperate and polar water masses. They are formed as a result of the uneven supply of solar heat at different latitudes and the influence of the atmosphere. In the same latitudes, the properties of surface water masses may differ, therefore, coastal and intra-oceanic masses are also distinguished.

Water masses actively interact with the atmosphere: they give it heat and moisture, absorb carbon dioxide from it, and release oxygen. When mixed, they change their properties.

What determines the salinity of ocean waters?
What are the differences in ocean water temperature?
Where does ice form in the ocean? How do they affect the nature of the Earth and human economic activity?
What is a water mass? Name the main types of water masses. What water masses are isolated in the surface layer of the ocean?

"Geography Lesson World Ocean" - Equipment: Islands are small areas of land surrounded on all sides by water. In all oceans there are seas - isolated islands, peninsulas. Working with atlases: show the islands. Summary of the lesson. Task: Write the name of the continents on the map. Parts of the oceans. Learning new material. Lesson Objectives:

"Problems of the World Ocean" - Environment subjected to unprecedented pollution in the history of mankind. Goals and objectives of the programs for the development of the World Ocean. The waters of the Baltic and North seas pose another danger as well. World Ocean. More obscure problems may arise due to the warming of the Earth's climate. The flooding operations were carried out in great haste and with serious violations of environmental safety standards.

"Secrets of the Ocean" - Gold. Divers. The main wealth is huge Natural resources. Ports. All seafood can be used for the benefit of man. At the bottom of the ocean. But the main consumers of water are industry and economy. Madagascar Island, Indian Ocean. The water level was considered the same for all open seas and oceans.

"The oceans and its parts" - Gulf of Mexico. peninsula of Somalia. Parts of the oceans. Pacific Ocean. South America. World Ocean: - oceans - seas - bays - straits. Part of the coastline of Russia. Atlantic Ocean. O. Greenland. World ocean = all oceans of the Earth taken together. Mediterranean Sea. North America. Strait of Gibraltar.

"Description of the Ocean" - Has no connection with the Arctic Ocean. The deepest ocean? Occupies 1/3 of the planet. It was mastered in antiquity by the Arabs. Into what oceans is the world ocean divided by continents? Give a description geographical location Arctic Ocean. Arctic Ocean. One of the islands Pacific Ocean. The smallest ocean

"Studying the World Ocean" - And so we found out that ... We are attracted to the ocean because: On our planet, life is possible without light and oxygen. We were not upset... And immediately - our bold assumption: Submariners answered... Books Magazines Resources Internet Stories of scientists. The ocean is made up of water and we are 90 percent water.