Geography lesson: how many oceans are on Earth. Toponymy (the origin of the names of continents and oceans) How many oceans are there in the world

When most of us were in school, 4 oceans were marked on the geographical maps of our planet: the Atlantic, the Pacific, the Indian and the Arctic. But on modern maps you can see the name of the 5th ocean - the South. What kind of ocean is this, and why did it become necessary to rewrite maps and change the number of oceans available?

The confusion with the oceans has been going on for centuries. For the first time, the term “Southern Ocean” is found on maps of the 17th century and denotes the expanses of the ocean surrounding the “Unknown Southern Continent”, which was not yet discovered at that time, the existence of which was suspected by travelers. The southern parts of the Atlantic, Indian and Pacific Oceans were very different in terms of navigation conditions: there were currents, strong winds and floating ice. For this reason, this region was sometimes singled out as a separate ocean, and in some cartographic materials of the 17th-18th centuries one can see the names "Southern Ocean", "Southern Arctic Ocean". Later, the name "Antarctic Ocean" began to occur.

Already after the discovery of Antarctica, in the middle of the 19th century, the Royal Geographical Society in London marked the boundaries of the Southern Ocean, referring to it the southern parts of the Pacific, Indian and Atlantic oceans, which are located between the Antarctic Circle and Antarctica. And the International Hydrographic Organization approved the existence of the Southern Ocean by 1937.

But later, scientists again came to the conclusion that the allocation of the Southern Ocean is inappropriate, and it again became part of the three oceans, and by the middle of the 20th century this name was no longer found either on sea charts or in school textbooks.

The need to separate the Southern Ocean was discussed again at the end of the 20th century. The waters of the three oceans surrounding Antarctica differ in many ways from the rest of the oceans. A powerful circumpolar current passes here, the species composition of the marine fauna is very different from warmer latitudes, and floating ice and icebergs are found everywhere around Antarctica. It can be said that the Southern Ocean was distinguished by analogy with the Arctic: too different natural conditions in the polar and subpolar territories of the ocean and in other parts of the World Ocean.

Member countries of the International Hydrographic Organization in 2000 decided to allocate the Southern Ocean, and its northern border was drawn along 60 parallels of south latitude. Since then, this name has appeared on world maps, and there are again 5 oceans on our planet.

World Ocean- the main part of the hydrosphere, a continuous, but not continuous water shell of the Earth, surrounding the continents and islands and characterized by a common salt composition. The world ocean is a heat regulator. The world ocean has the richest food, mineral and energy resources. Although the World Ocean is a single whole, for the convenience of research, its individual parts have been given different names: the Pacific, Atlantic, Indian, Arctic Oceans and the South.

Ocean and atmosphere. The oceans, the average depth of which is approx. 4 km, contains 1350 million km3 of water. The atmosphere, enveloping the entire Earth in a layer several hundred kilometers thick, with a much larger base than the World Ocean, can be considered as a "shell". Both the ocean and the atmosphere are the fluids in which life exists; their properties determine the habitat of organisms. The ocean determines the main properties of the atmosphere and is a source of energy for many processes occurring in the atmosphere. The circulation of water in the ocean is affected by winds, the rotation of the Earth, and land barriers.

Ocean and climate. It is well known that the temperature regime and other climatic characteristics of the area at any latitude can change significantly in the direction from the ocean coast to the interior of the mainland. Compared to land, the ocean heats up more slowly in summer and cools more slowly in winter, smoothing out temperature fluctuations on adjacent land.

Composition of sea water. The ocean water is salty. Salty taste is given by the 3.5% of dissolved minerals contained in it - mainly sodium and chlorine compounds - the main ingredients of table salt. Magnesium is next in number, followed by sulfur; all common metals are also present. Of the non-metallic components, calcium and silicon are especially important, since they are involved in the structure of the skeletons and shells of many marine animals. Due to the fact that the water in the ocean is constantly mixed by waves and currents, its composition is almost the same in all oceans.

properties of sea water. The density of sea water (at a temperature of 20 ° C and salinity approx. 3.5%) is approximately 1.03, i.e. slightly higher than the density of fresh water (1.0). The density of water in the ocean varies with depth due to the pressure of the overlying layers, as well as depending on temperature and salinity. In the deepest parts of the ocean, the waters tend to be saltier and colder. The densest masses of water in the ocean can remain at depth and maintain a lower temperature for more than 1000 years.

Sea water is much less transparent to visible light than air, but more transparent than most other substances. The penetration of sunlight into the ocean to a depth of 700 m has been recorded. Radio waves penetrate the water column only to a shallow depth, but sound waves can propagate under water for thousands of kilometers. The speed of sound propagation in sea water fluctuates, averaging 1500 m per second.

The surface of our planet is 71% covered by oceans, which make up 97% of the Earth's water. According to experts, only 5% of the ocean depths have been explored so far. The world ocean is the main component of the planet's hydrosphere, affecting weather and climatic conditions. About 2 million species of animals live in it, the vast majority of which have not yet been studied.

All water bodies that are part of the World Water have a significant impact on climatic features, flora and fauna of our planet. Consider how many oceans are on Earth, their characteristics and features.

Until recently, it was generally accepted that there were only 4 oceans in the world.

Note! In 2000, representatives of scientific organizations identified a new ocean, which was called the South.

The list looks like this:

• Quiet;
• Atlantic;
• Indian;
• Southern (Antarctic);
• Arctic (Arctic).

Thus, it turns out that there are 5 oceans on Earth. Using modern developments and scientific and technological achievements, scientists can explore the water expanses of our planet in new and unique ways.

This allows not only to study the depths of these reservoirs, but also to prevent the likely catastrophic consequences that can occur due to climate change in these areas.

Also, new species of living organisms are regularly discovered, many of which amaze the imagination. However, most of them remain unknown.

world ocean planet

The oceans are the planetary salt water column, which includes all known water resources. There is a free exchange between parts of this continuous reservoir, which is important for oceanography.

Several criteria are used to determine the most important oceanic areas, for example, archipelagos, continents.

Quiet

The largest (179 million km², it takes up a third of the surface of the entire planet and half of the world) and ancient among all the others. It is often referred to as the "Great", because it is able to accommodate every continent and island of the Earth.

The reservoir received its official name after F. Magellan's round-the-world trip, during which good calm weather reigned.

The shape is oval, widened at the equator. It is bounded in the west by the mainland of North and South America, in the east by the mainland of Australia and Eurasia.

The South Pacific is characterized by light, gentle winds, stable weather conditions, but to the west, the situation changes: hurricanes are often observed here - southern Australian squalls, gaining strength in December.

Tropical waters are transparent, clean, dark blue in color, their degree of salinity is medium. The weather in the equatorial region is favorable: moderate winds, 25 degrees Celsius all year round, calm is often observed, clear skies. The Great Coral Reef stretches along the eastern coast of Australia.

The average depth is 3980 meters, the greatest is in the Mariana Trench (11022 m). Volcanic eruptions and tremors are often observed on the coast, both in depth and on the surface of the Earth.

Many species of living creatures live in the Pacific - a variety of fish, seals, crabs, octopuses, etc.

The Pacific Ocean plays an important role in the economy of a huge number of states. 50% of the world's catch comes from this reservoir. The most important sea routes pass through it. Shipping is actively carried out along the coast of the continents.

Unfortunately, human activity has become the cause of water pollution, and several species of animals were destroyed. Especially dangerous for the reservoir is the ingress of industrial waste and oil into the water.

Atlantic

This is the second largest ocean on our planet, which is the most developed and explored. The length is 13,000 km, the maximum width is 6,700 km, and the area is 92 km². Its coastline is significantly indented, which forms a huge number of bays and seas, especially in the northern regions.

From the west it is bounded by South and North America, from the east by Africa and Europe.

It was first described in the 5th century BC by Herodotus, the historian of Ancient Greece.

This reservoir cannot boast of the diversity of the animal world, but only the abundance of biomass. Since ancient times, the Atlantic has been the main place for the extraction of mammals and marine fish.

It has a strong influence on the climate of the entire planet. Thanks to the Gulf Stream, European countries are warmed by warm waters.

The increased economic activity of mankind has greatly worsened the environment in the reservoir itself and on the nearby coasts. Today, scientific recommendations are being actively drawn up, international treaties are being concluded aimed at the reasonable exploitation of ocean resources.

Indian

This reservoir is allocated one fifth of the area of ​​all the world's waters and the seventh - of the entire surface of the Earth. Its area is 76 million km². The most salty part of it is the Red Sea (the degree of salinity is 41%). The reservoir is limited to three continents - Australia, Asia and Africa.

The Indian one is distinguished by a diverse relief: at its bottom there are underwater ridges, basins, and gutters.

The vast majority is in the Southern Hemisphere.

Indian in terms of surface water temperatures is the warmest. Monsoons are observed in its northern part.

Indian is distinguished by a developed animal and plant world. Offshore production of natural gas and oil. On the surface of the reservoir there are many navigable routes.

Compared to the other five oceans, the Indian Ocean is the most oil-polluted in the world.

One of the most dangerous natural disasters in the history of mankind happened in December 2004 - an earthquake, the epicenter of which was in this ocean, caused an underwater earthquake in this reservoir. Waves 15 meters high reached the shores of many countries - Thailand, Sri Lanka, Indonesia, etc., which caused a huge number of victims (about 300 thousand). Many of the bodies were carried away by the water into the sea, so the exact number of dead could not be established.

Southern (Antarctic)

It ranks fourth in size. It surrounds Antarctica and covers an area of ​​86 million km². The greatest depth is about 8428 m, the average is 3500 m.

The southern one has a harsh climate and a rich wildlife. Krill is being harvested, but whaling is banned. The total number of whales is 500,000. There are such representatives of mammals: seals, southern elephant seals, sea leopards. The coast is home to 44 different species of birds, numbering 200 million.

Climatic conditions are made up of several distinctive features: a unique geographical position, the influence of the mainland of Antarctica (ice-covered, high-mountainous and cold), incessant sea ice. Warm currents are not observed. Katabatic winds are formed, the speed of which can sometimes reach 15 m/s.

One of the characteristic features of the Southern water resource is the year-round presence of ice. From September to October, during the period of greatest development, ice covers an area of ​​​​about 18 million km².

Icebergs are also formed due to the fact that under the influence of tsunamis and waves, coastal parts of ice and continental glaciers break off. Every year in the waters of this reservoir are observed from 200 thousand icebergs. They rise 50 m above the sea surface, and their length is approximately 500 m. Over 4-5 years, the vast majority of the mass of icebergs thaws.

Arctic (Arctic)

Located between North America and Eurasia.

Note! This is the smallest ocean of our entire planet.

It covers an area equal to 15 million km², which forms only a few percent of the world's waters as a whole.

The depth of the reservoir is 1225 m (maximum - 5527 m - in the Greenland Sea). As a result, the Arctic is the most shallow. The ice of the Arctic is like a huge white giant, which contains 10 percent of the world's fresh water reserves. It maintains the stability of the Earth's global climate.

The area of ​​the islands is 4 million km². The largest archipelagos and islands are Svalbard, Novaya Zemlya, Franz Josef Land, the Vaigach, Kolguev, Wrangel Islands, etc. Greenland Island is also located within the oceanic waters of the Arctic.

The climate of this reservoir belongs to the arctic. The vast majority in the winter months of the year is covered with drifting ice. In the summer months, the water temperature rises to +5 degrees.

Polar bears can be found on floating ice. They use the ice as a platform and for hunting. When the ice disappears, these animals will also disappear, as they will begin to starve. At the same time, polar bears live only in the Arctic.

The indigenous population is engaged in fishing for seals and walruses. Fishing is also developed. In the Arctic, there are fish that live only in these territories.

When the ice of the reservoir melts, they release various organisms and nutrients into the water, due to which algae begins to grow. Representatives of the underwater world feed on zooplankton.

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Summing up

How many oceans in our world, on the planet are accrued at the moment? There are 5 of them on Earth, and the fifth, the Southern (Antarctic), officially “appeared” only a few years ago. All the oceans of the world play a vital role in the life of our planet.

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The origin of the oceans on Earth is still unknown. However, we know that about 360 million square kilometers of salt water covers our planet. It is divided into several major 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 ocean is the main component of the Earth's hydrosphere, therefore it is an integral part of life, forms part of the carbon cycle and globally affects climate and weather conditions. The ocean is home to 230,000 known animal species, and possibly over two million underwater species, as most of them are unexplored.

How many oceans on Earth: 5 or 4

I wonder, actually, how many oceans are there 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.

The 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, a global, interconnected body of salt water is sometimes referred to as the World Ocean. The concept of a continuous body of water with relatively free exchange between its parts is fundamental to oceanography.

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

Oceans that exist, their location

Quiet, the largest, extends north from the Southern Ocean to the North. It spans the gap between Australia, Asia and America and meets the Atlantic just south of South America at Cape Horn. Pacific - 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 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 merges into the Pacific expanses in the east, not far from Australia. Indian - washes 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 at the Bering Strait and spans the North Pole, touching North America in the Western Hemisphere, Scandinavia and Siberia in the Eastern Hemisphere. Almost all of it is covered with sea ice, the extent of which varies depending on the season. Arctic - covers most of the Arctic and washes North America and Eurasia. The area is 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 flow prevails. This maritime space has only recently been identified as a separate oceanic unit, which is located south of sixty degrees south latitude and is partially covered by sea ice, the size of which depends on the season. Southern - sometimes seen as an extension of the Pacific, Atlantic and Indian Oceans that surrounds 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 are over 3,000 meters deep. Huge spaces below 200 meters deep cover about 66% of the Earth's surface.
4. The bluish color of the water is a constituent of 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 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 down to a depth of 200 m; it is an area where photosynthesis takes place and is therefore highly biodiverse.

Because plants require photosynthesis, life found deeper than the photon zone must either rely on material descending from above or find another energy source. Hydrothermal vents are the main source of energy in the so-called aphotic zone (more than 200 m deep). The pelagic part of the photon zone is known as the 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 strongly influence the Earth's climate, transferring heat from the tropics to the polar regions. By transferring warm or cold air and precipitation to coastal regions, winds can carry it inland.

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

The ocean is the largest object and is the part that covers about 71% of our planet's surface. The oceans wash the shores of the continents, have a system of water circulation and have other specific features. The oceans of the world are in constant interaction with everyone.

Map of oceans and continents of the world

Some sources indicate that the World Ocean is divided into 4 oceans, but in 2000 the International Hydrographic Organization singled out the fifth - the Southern Ocean. This article provides a list of all 5 oceans of planet Earth in order - from the largest in area to the smallest, with the name, location on the map and main characteristics.

Pacific Ocean

The Pacific Ocean on a map of the Earth / Wikipedia

Due to its large size, the Pacific Ocean has a unique and varied topography. It also plays an important role in shaping the world's weather patterns and the modern economy.

The ocean floor is constantly changing through the movement and subduction of tectonic plates. Currently, the oldest known area of ​​the Pacific Ocean is about 180 million years old.

In terms of geology, the area surrounding the Pacific Ocean is sometimes called. The region has this name because it is the world's largest area of ​​volcanism and earthquakes. The Pacific region is subject to violent geological activity, because much of its floor is in subduction zones, where the boundaries of some tectonic plates are pushed under others after a collision. There are also some hotspot areas where magma from the Earth's mantle is forced out through the Earth's crust, creating underwater volcanoes that can eventually form islands and seamounts.

The Pacific Ocean has a diverse bottom topography, consisting of oceanic ridges and which formed in hot spots below the surface. The relief of the ocean differs significantly from large continents and islands. The deepest point of the Pacific Ocean is called the "Challenger Abyss", it is located in the Mariana Trench, at a depth of almost 11 thousand km. The largest is New Guinea.

The climate of the ocean varies greatly depending on the latitude, the presence of land, and the types of air masses moving over its waters. Ocean surface temperature also plays a role in climate as it affects the availability of moisture in different regions. The climate in the vicinity is humid and warm during most of the year. The far north Pacific and the far south are more temperate, with large seasonal variations in weather patterns. In addition, some regions are dominated by seasonal trade winds that affect the climate. Tropical cyclones and typhoons also form in the Pacific Ocean.

The Pacific Ocean is almost the same as in other oceans of the Earth, with the exception of local temperatures and salinity of the water. The pelagic zone of the ocean is inhabited by marine animals, such as fish, marine and. Organisms and scavengers live at the bottom. Habitats can be found in sunny shallow areas of the ocean near the coast. The Pacific Ocean is the environment that hosts the greatest variety of living organisms on the planet.

Atlantic Ocean

Atlantic Ocean on a map of the Earth / Wikipedia

The Atlantic Ocean is the second largest ocean on Earth with a total area (including adjacent seas) of 106.46 million km². It occupies about 22% of the planet's surface area. The ocean has an elongated S-shape and extends between North and South America in the west, as well as , and - in the east. It connects to the Arctic Ocean to the north, the Pacific Ocean to the southwest, the Indian Ocean to the southeast, and the Southern Ocean to the south. The average depth of the Atlantic Ocean is 3,926 m, and the deepest point is located in the Puerto Rico Ocean Trench, at a depth of 8,605 m. The Atlantic Ocean has the highest salinity of any ocean in the world.

Its climate is characterized by warm or cool water, which circulates in different currents. Water depth and winds also have a significant effect on ocean surface weather. Severe Atlantic hurricanes are known to develop off the coast of Cape Verde in Africa, heading towards the Caribbean from August to November.

The time when the supercontinent Pangea broke up, about 130 million years ago, was the beginning of the formation of the Atlantic Ocean. Geologists have determined that it is the second youngest of the world's five oceans. This ocean has played a very important role in connecting the Old World with the newly explored America since the late 15th century.

The main feature of the floor of the Atlantic Ocean is an underwater mountain range called the Mid-Atlantic Ridge, which extends from Iceland in the north to approximately 58°S. sh. and has a maximum width of about 1600 km. The water depth above the ridge is less than 2,700 meters in most places, and several mountain peaks of the ridge rise above the water to form islands.

The Atlantic Ocean flows into the Pacific Ocean, however they are not always the same due to water temperature, ocean currents, sunlight, nutrients, salinity, etc. The Atlantic Ocean has coastal and open ocean habitats. Its coastal areas are located along the coastlines and extend to the continental shelves. Marine life is usually concentrated in the upper layers of the ocean, and closer to the shores are coral reefs, algae forests and sea grasses.

The Atlantic Ocean is of great modern importance. The construction of the Panama Canal, located in Central America, allowed large ships to pass through the waterways, from Asia across the Pacific Ocean to the east coast of North and South America across the Atlantic Ocean. This led to a revival of trade between Europe, Asia, South America and North America. In addition, there are deposits of gas, oil and precious stones at the bottom of the Atlantic Ocean.

Indian Ocean

Indian Ocean on a map of the Earth / Wikipedia

The Indian Ocean is the third largest ocean on the planet and has an area of ​​70.56 million km². It is located between Africa, Asia, Australia and the Southern Ocean. The Indian Ocean has an average depth of 3,963 m, and the Sunda Trench is the deepest trench, with a maximum depth of 7,258 m. The Indian Ocean occupies about 20% of the area of ​​the World Ocean.

The formation of this ocean is a consequence of the breakup of the Gondwana supercontinent, which began about 180 million years ago. 36 million years ago, the Indian Ocean assumed its current configuration. Although it first opened about 140 million years ago, almost all Indian Ocean basins are less than 80 million years old.

It is landlocked and does not extend into arctic waters. It has fewer islands and narrower continental shelves compared to the Pacific and Atlantic Oceans. Below the surface layers, especially in the north, the ocean water is extremely low in oxygen.

The climate of the Indian Ocean varies considerably from north to south. For example, monsoons dominate in the northern part, above the equator. From October to April, strong northeasterly winds are observed, while from May to October - southerly and western ones. The Indian Ocean also has the warmest weather of all five oceans in the world.

The ocean depths contain about 40% of the world's offshore oil, and seven countries currently produce from this ocean.

The Seychelles is an archipelago in the Indian Ocean consisting of 115 islands and most of them are granitic islands and coral islands. On granitic islands, most of the species are endemic, and coral islands have a coral reef ecosystem, where the biodiversity of marine life is greatest. The Indian Ocean has an island fauna that includes sea turtles, seabirds and many other exotic animals. Much of the marine life in the Indian Ocean is endemic.

The entire marine ecosystem of the Indian Ocean is facing species decline as water temperatures continue to rise, which in turn results in a 20% decline in phytoplankton, on which the marine food chain is highly dependent.

South ocean

Southern Ocean on a map of the Earth/Wikipedia

In 2000, the International Hydrographic Organization singled out the fifth, youngest ocean in the world - the Southern Ocean - from the southern regions of the Atlantic, Indian and Pacific oceans. The New Southern Ocean completely surrounds and extends from its coast north to 60°S. sh. The Southern Ocean is by far the fourth largest of the world's five oceans, only larger than the Arctic Ocean.

In recent years, a large amount of oceanographic research has focused on ocean currents, first due to El Niño and then due to the wider interest in global warming. One of the studies determined that currents near Antarctica isolate the Southern Ocean as a separate one, so it was identified as a separate, fifth ocean.

The area of ​​the Southern Ocean is approximately 20.3 million km². The deepest point is 7,235 meters deep and is located in the South Sandwich Trench.

The water temperature in the Southern Ocean varies from -2° C to +10° C. It also contains the largest and most powerful cold surface current on Earth - the Antarctic Circumpolar Current, which moves eastward and is 100 times the flow of all the world's rivers.

Despite the allocation of this new ocean, it is likely that the discussion about the number of oceans will continue in the future. After all, there is only one "World Ocean" since all 5 (or 4) oceans on our planet are interconnected with each other.

Arctic Ocean

The Arctic Ocean on the map of the Earth / Wikipedia

The Arctic Ocean is the smallest of the world's five oceans and has an area of ​​14.06 million km². Its average depth is 1205 m, and the deepest point is in the underwater Nansen Basin, at a depth of 4665 m. The Arctic Ocean is located between Europe, Asia and North America. In addition, most of its waters are north of the Arctic Circle. located in the center of the Arctic Ocean.

While located on a continent, the North Pole is covered in water. For most of the year, the Arctic Ocean is almost completely covered by drifting polar ice, which is about three meters thick. This glacier usually melts during the summer months, but only partially.

Due to its small size, many oceanographers do not consider it an ocean. Instead, some scientists suggest that it is a sea that is mostly enclosed by continents. Others believe that this is a partially closed coastal body of the Atlantic Ocean. These theories are not widely held, and the International Hydrographic Organization considers the Arctic Ocean one of the world's five oceans.

The Arctic Ocean has the lowest water salinity of any of the Earth's oceans due to the low evaporation rate and fresh water coming from streams and rivers that feed the ocean, diluting the salt concentration in the water.

The polar climate dominates this ocean. Consequently, winters exhibit relatively stable weather with low temperatures. The best known characteristics of this climate are polar nights and polar days.

It is believed that the Arctic Ocean may contain about 25% of the total natural gas and oil reserves on our planet. Geologists have also established that there are significant deposits of gold and other minerals. The abundance of several species of fish and seals also make the region attractive to the fishing industry.

There are several animal habitats in the Arctic Ocean, including endangered mammals and fish. The region's vulnerable ecosystem is one of the factors that make the fauna so sensitive to climate change. Some of these species are endemic and irreplaceable. The summer months bring an abundance of phytoplankton which, in turn, feeds the base, which eventually ends up with large terrestrial and marine mammals.

Recent developments in technology are enabling scientists to explore the depths of the world's oceans in new ways. These studies are needed to help scientists study and possibly prevent the catastrophic effects of climate change in these areas, as well as to discover new types of living organisms.