The Sargasso Sea is located in the middle of the North Atlantic Ocean. The most interesting thing is that this sea is limited not by land, but by currents: in the west - by the Gulf Stream, in the north - by the North Atlantic Current, in the east - by the Canary Current, and in the south - by the North Atlantic Equatorial Current

Warm currents. The most famous warm current is the Gulf Stream. Each sea current is a "stove" on the planetary "weather kitchen" or a "refrigerator". The Gulf Stream is a unique “slab”. After all, the life of the whole European continent depends on its whims. It has a great influence on the climate, hydrological and biological conditions of the North Atlantic Ocean and the western part of the Arctic Ocean. In the south, the width of the Gulf Stream is 75 km, the thickness of the stream is m, and the speed reaches 300 cm / s. The surface water temperature is between 24 and 28 °C. In the area of ​​the Great Newfoundland Bank, the width of the Gulf Stream already reaches 200 km, and the speed decreases to 80 cm / s, and the water temperature is ° C. In the Arctic Ocean, the waters of the Gulf Stream form a warm intermediate layer after they sink north of Svalbard.

Importance of sea currents. Sea currents have a great influence on the climate. Warm currents during the cold period increase the temperature and give precipitation. For example, in Russia there is a non-freezing port of Murmansk, which is located beyond the Arctic Circle. The reason for this is the North Atlantic warm current. The cold current of the warm period lowers the temperature and does not give precipitation, for example, the Atacama Desert formed off the coast of South America, the reason for this is the cold Peruvian current.

Main sources used. 1. Atlantic Ocean / Ed. ed. V. G. Kort. S. S. Salnikov - L. Science, p. 2. Weil P. Popular oceanography \ Per. with. English – L Gidrometeoizdat

Surface currents in the North Atlantic Ocean move clockwise. The main elements of this large system are the warm current of the Gulf Stream directed to the north, as well as the North Atlantic, Canary and Northern Equatorial (Equatorial) currents. The Gulf Stream follows from the Strait of Florida and the island of Cuba in a northerly direction along the coast of the United States and approximately 40 N. latitude. deviates to the northeast, changing its name to the North Atlantic Current. This current divides into two branches, one of which follows the northeast along the coast of Norway and further into the Arctic Ocean. The second branch turns south and further southwest along the coast of Africa, forming the cold Canary Current. This current moves to the southwest and joins the North Equatorial Current, which heads west towards the West Indies, where it merges with the Gulf Stream. To the north of the North Equatorial Current is an area of ​​stagnant water, abundant in algae and known as the Sargasso Sea. Along the North Atlantic coast of North America, the cold Labrador Current passes from north to south, following from the Baffin Bay and the Labrador Sea and cooling the coast of New England.

The main current systems in the South Atlantic move counterclockwise. The South Tradewind current is directed to the west. At the protrusion of the east coast of Brazil, it divides into two branches: the northern one carries water along the northern coast of South America to the Caribbean, and the southern, warm Brazilian Current, moves south along the coast of Brazil and joins the West Winds Current, or Antarctic, which heads east and then to the northeast. Part of this cold current separates and carries its waters north along the African coast, forming the cold Benguela Current; the latter eventually joins the South Equatorial Current. The warm Guinea Current moves south along the coast of Northwest Africa to the Gulf of Guinea.

Surface currents of the Pacific Ocean

The Pacific Ocean is quite strongly elongated from west to east, so it is dominated by latitudinal water flows. In the ocean, 2 huge rings of water movements are formed: 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 southern trade winds, the East Australian, the westerly winds and the Peruvian. Currents have a significant impact on the redistribution of heat in the ocean and on the nature of adjacent continents. So the trade winds drive warm waters away from the western tropical coasts of the continents to the eastern ones, therefore, in low latitudes, the western part of the ocean is much warmer than the eastern one. In the middle high latitudes, on the contrary, the eastern parts are warmer than the western ones.

Surface currents of the Indian Ocean

In the northern part of the ocean, monsoonal circulation causes a seasonal change in currents. In winter, the Southwest Monsoon Current sets in, originating in the Bay of Bengal. South of 10 N this current passes into the Western Current, crossing the ocean from the Nicobar Islands to the coast of East Africa, where it branches. One branch goes to the Red Sea, the other goes south to 10S. and then, acquiring an easterly direction, gives rise to the Equatorial Countercurrent. The latter crosses the ocean and branches off the coast of Sumatra again - part of the water goes into the Andaman Sea, and the main branch goes between the Small Sunda Islands and the northern coast of Australia to the Pacific Ocean. In summer, the southeast monsoon ensures the movement of the entire mass of surface waters to the east, and the equatorial current weakens. The summer monsoon current begins off the coast of Africa with a powerful Somali current, which is joined by a current from the Red Sea in the Gulf of Aden. In the Bay of Bengal, the summer monsoon current forms a flow to the north, the other part of the waters goes south and joins the South Trade Wind Current. In general, the system of currents in the Indian Ocean can be represented as two main gyres. In winter (northern hemisphere) stands out the northern circulation, formed by the Monsoon, Somali and Equatorial currents. In the summer of the northern hemisphere, the monsoon current, which acquires the opposite direction, merges with the Equatorial one and sharply strengthens it. As a result, the northern circulation is closed from the south by the South Tradewind current. The second, southern gyre is formed by the currents of the South Tradewind, Madagascar, Agulians, West Winds and West Australian. In the Arabian Sea, the Bay of Bengal and the Great Australian Bay, and in the Antarctic waters, local gyres operate.

At first glance, the world's oceans appear to be a giant static reservoir of salt water, the only movement in which is carried out in the form of waves. However, this is far from being the case - in each ocean there are dozens of large and small currents that affect a significant part of their area. The Atlantic Ocean is no exception.

Classification of the sea currents of the Atlantic

For a long time, the Atlantic has been famous for its sea currents; sailors have been using them for many centuries as a wide sea "road". Sea currents of the Atlantic Ocean are two large circles of circulation, almost isolated from each other. One of them is located in the northern part of the ocean, and the second in the south. At the same time, in the southern "circle" the water moves counterclockwise, and in the northern part of the Atlantic - on the contrary, clockwise. This direction of movement is due to the Coriolis law.

These circulation "circles" are not strictly isolated - turbulent eddies form on their outer edges in the form of separating flows. In the northern hemisphere, the most famous is Greenland, gradually turning into Labrador. In the southern hemisphere, the Guiana Current separates from the South Trade Wind, rushing north and joining there with the North Trade Wind.

All sea ​​currents of the atlantic ocean divided into warm and cold. But such a division is purely conditional. In systematics, their main role is played by the temperature of the surrounding mass of water. For example, conventionally, the course of the North Cape has an average temperature of 6-8 ° C, but it is considered warm, because the temperature of the Barents Sea, into which it flows, is only 2-4 degrees. Similarly, the Canary current is considered cold, although its temperature is much higher than that of the North Cape.

In addition to separation by temperature, the sea currents of the Atlantic Ocean are:

• Gradient - caused by the difference in temperature and density of water in different parts of the sea.
• Wind (drift) - they arise under the influence of winds, most often blowing in a given area of ​​\u200b\u200bthe ocean.
• Tidal, arising under the influence of the force of attraction of the moon and the sun.

Causes of sea currents

The main causes of sea currents in the Atlantic Ocean are:

• Coriolis force arising as a result of the inertia of a liquid medium. The mass of water that fills the ocean simply does not keep up with the planet rotating around its axis.
• The difference in temperature and density of water. These factors are decisive for the emergence of deep currents.
• The effect of winds on the ocean surface.

All of these factors are not isolated, but affect the ocean in a complex, leading to the emergence of water circulation. For the most part, the currents affect spaces limited in depth, not exceeding a few hundred meters. But in width they can reach several hundred, or even a thousand kilometers. For example, the subantarctic current of the West Winds is sometimes up to 2,000 km wide, moving 270 million cubic meters of water per second, which is 2,000 times the volume of the Amazon.

The main sea currents of the Atlantic Ocean

There are several tens (or even hundreds) of permanent sea currents in the Atlantic. It is simply not possible to list all of them. Let's dwell on the most significant. To main sea ​​currents of the atlantic ocean relate:

• Gulfstream. This is perhaps one of the most grandiose and widely known course of the Atlantic Ocean. Its average width is 100-150 km, and the depth reaches 1 km. The total volume of water moved by it is about 75 million m3, which is ten times more than the volume of all the rivers of the planet. It originates in the Gulf of Mexico, which is reflected in the name: gulf stream - “the course of the gulf”. Further, it goes along the east coast of the United States, gradually deviating to the east.
• North Atlantic. To the southeast of the Newfoundland peninsula, the Gulf Stream splits into two new streams: the North Atlantic Current and the Canary. The North Atlantic, carrying warm water, continues the path of the Gulf Stream to the east, and reaches the northwestern coast of Europe, causing a mild climate there. In the Faroe region, the northern Greenland current separates from it, and the rest goes around Norway in the form of the North Cape current and reaches the Barents Sea. Thanks to him, we have an ice-free port of Murmansk on the shores of the Arctic Ocean.
• Canarian. It is the southern, right branch of the North Atlantic Sea Current. Passing along the western coast of the Iberian Peninsula and Morocco, it reaches the Canaries, losing its strength. However, the transatlantic North Trade Wind Current originates from these places.
• Northern trade wind. It is one of the longest major sea currents in the Atlantic Ocean. It originates off the coast of Morocco and reaches the American continent in the Caribbean. Here it flows into the Caribbean Sea, smoothly turning into small currents, eventually giving rise to the Gulf Stream. Thus, the great North Atlantic circle is closed.

The southern circulation originates off the southwestern coast of Africa in the form of the cold Benguela Current (named after the coastal city in Angola). Further, heating up, the flow of water is deflected by the trade winds blowing from the continent to the west, becoming the South Trade Wind Current. At the northwestern tip of Brazil, it is divided into two branches: the Guiana Current deviates to the north, and the Brazilian Current to the south. The latter reaches the high Antarctic latitudes, merging with the course of the Western winds. The cooled mass of water is transferred to the east, to the coast of South Africa, closing the southern circle. sea ​​currents of the atlantic ocean.

Using the sea currents of the Atlantic Ocean

Sailors have long used the sea currents of the Atlantic to optimize movement. The most widely known example is the journey of Christopher Columbus, who descended from Spain along the Canary Current to the place of formation of the "transatlantic" - the North Trade Wind Current. It was more or less safe and delivered him to the West Indies.

The use of the sea currents of the Atlantic Ocean does not lose its relevance today. If you decide to make a transatlantic crossing, then you should not “reinvent the wheel”, but simply use the sea route beaten centuries ago. That is, you need to go down to the Canary Islands or the Cape Verde Islands (Cape Verde), and go straight to the New World with a fair wind and current. To some extent, it will be like rafting on a slow and wide river, of course, with adjustments for the far from riverine nature of the open ocean. No wonder experienced sailors say: any item dropped into the water off the Canary Islands will be caught in the Caribbean in a few months.

It is best to return back to Europe by the northern route, through the Gulf Stream. Sailors also have a saying about this: “The way from the Canary Islands to Europe lies through America.” This means that it is much easier to sail back from the Canary Islands via the Caribbean than to go against the grain, against the prevailing winds and the Canary current, despite the huge increase in the total length of the route. Of course, for motorized ships, the old marine advice is of little relevance, especially if there is an adequate supply of fuel on board.

Further, having reached the Caribbean Sea, along the Florida current we get to the sources of the Gulf Stream, and we rise along this grandiose sea "river" to approximately 40 o. After that, we turn east and after a certain time, following the south of the North Atlantic Stream, we reach the western tip of Europe. It was this route that Columbus returned from his voyages to the West Indies.

When using the Gulf Stream, experienced yachtsmen do not advise to rise above 40 degrees. At higher latitudes, the warm waters of the Gulf Stream collide with the northern Labrador Current, with all the resulting climatic delights: a sudden change in winds, frequent fogs and storms. No wonder the northeast coast of the United States and the Newfoundland region has long been called the "rotten corner of the Atlantic." In winter, one should also not forget about the possibility of icebergs being carried south by the Labrador Current - does anyone else remember the 20th century blockbuster Titanic?

Ocean water is on the move, affecting your climate, your local ecosystem, and the seafood you eat. Ocean currents, abiotic features of the environment, are continuous and directed movements of ocean water. These currents are located in the depths of the ocean and on its surface, flowing both locally and globally.

The most important and unique currents of the Atlantic Ocean

• Equatorial north current. This current is created due to the rise of cold water near the African west coast. The warm current is also pushed westward by the cool Canarian current.
• The Equatorial South Current flows from the west coast of Africa to the coast of South America between the equator and latitude 20°. This current is more constant, stronger and more powerful than the north equatorial current. In fact, this current is a continuation of the Benguela current.
• The Gulf Stream consists of several currents that are directed in a northeasterly direction. This current system originates in the Gulf of Mexico and reaches the western coasts of Europe around 70°N.
• The Florida Stream is a continuation of the well-known equatorial current to the north. This current flows through the Yucatán Channel into the Gulf of Mexico, after which the current moves forward through the Strait of Florida and reaches 30°N.
• The Canary Current, it is the coolest, which flows along the western coast of North Africa between Madeira and Cape Verde. In fact, this current is a continuation of the North Atlantic drift, which turns south near the Spanish coast and flows south along the coast of the island of the Canary Islands. The approximate current speed is between 8 and 30 nautical miles.
• The Labrador Current, an example of a cold current, originates in Baffin Bay and Davis Strait and, after flowing through the coastal waters of Newfoundland and the Grand Bank, merges with the Gulf Stream at about 50°W. The flow rate is 7.5 million m3 of water per second.

Navigators learned about the presence of ocean currents almost immediately, as soon as they began to surf the waters of the oceans. True, the public paid attention to them only when, thanks to the movement of ocean waters, many great geographical discoveries were made, for example, Christopher Columbus sailed to America thanks to the North Equatorial Current. After that, not only sailors, but also scientists began to pay close attention to ocean currents and strive to explore them as best and as deeply as possible.

Already in the second half of the XVIII century. sailors studied the Gulf Stream quite well and successfully applied their knowledge in practice: they went with the flow from America to Great Britain, and kept a certain distance in the opposite direction. This allowed them to be two weeks ahead of ships whose captains were not familiar with the terrain.

Oceanic or sea currents are large-scale movements of the water masses of the World Ocean at a speed of 1 to 9 km / h. These streams do not move randomly, but in a certain channel and direction, which is the main reason why they are sometimes called the rivers of the oceans: the width of the largest currents can be several hundred kilometers, and the length can reach more than one thousand.

It has been established that water flows do not move straight, but deviating slightly to the side, they obey the Coriolis force. In the Northern Hemisphere they almost always move clockwise, in the Southern Hemisphere it is vice versa.. At the same time, currents located in tropical latitudes (they are called equatorial or trade winds) move mainly from east to west. The strongest currents were recorded along the eastern coasts of the continents.

Water flows do not circulate on their own, but they are set in motion by a sufficient number of factors - the wind, the rotation of the planet around its axis, the gravitational fields of the Earth and the Moon, the bottom topography, the outlines of continents and islands, the difference in temperature indicators of water, its density, depth in various places of the ocean and even its physico-chemical composition.

Of all the types of water flows, the most pronounced are the surface currents of the World Ocean, the depth of which is often several hundred meters. Their occurrence was influenced by trade winds, constantly moving in tropical latitudes in a west-east direction. These trade winds form huge streams of the North and South Equatorial currents near the equator. A smaller part of these flows returns to the east, forming a countercurrent (when the movement of water occurs in the opposite direction from the movement of air masses). Most, colliding with the continents and islands, turns to the north or south.

Warm and cold water streams

It must be taken into account that the concepts of "cold" or "warm" currents are conditional definitions. So, despite the fact that the temperature indicators of the water flows of the Benguela Current, which flows along the Cape of Good Hope, are 20 ° C, it is considered cold. But the North Cape Current, which is one of the branches of the Gulf Stream, with temperatures ranging from 4 to 6 ° C, is warm.

This happens because the cold, warm and neutral currents got their names based on a comparison of the temperature of their water with the temperature indicators of the ocean surrounding them:

• If the temperature indicators of the water flow coincide with the temperature of the waters surrounding it, such a flow is called neutral;
• If the temperature of the currents is lower than the surrounding water, they are called cold. They usually flow from high latitudes to low latitudes (for example, the Labrador Current), or from areas where, due to the large flow of rivers, ocean water has a reduced salinity of surface water;
• If the temperature of the currents is warmer than the surrounding water, then they are called warm. They move from the tropics to subpolar latitudes, such as the Gulf Stream.

Main water flows

At the moment, scientists have recorded about fifteen major oceanic water flows in the Pacific, fourteen in the Atlantic, seven in the Indian and four in the Arctic Ocean.

It is interesting that all the currents of the Arctic Ocean move at the same speed - 50 cm / s, three of them, namely the West Greenland, West Svalbard and Norwegian, are warm, and only the East Greenland belongs to the cold current.

But almost all oceanic currents of the Indian Ocean are warm or neutral, while the Monsoon, Somali, West Australian and the Cape of Needles (cold) move at a speed of 70 cm / s, the speed of the rest varies from 25 to 75 cm / s. The water flows of this ocean are interesting because, along with the seasonal monsoon winds, which change their direction twice a year, ocean rivers also change their course: in winter they mainly flow west, in summer - east (a phenomenon characteristic only of the Indian Ocean). ).

Since the Atlantic Ocean stretches from north to south, its currents also have a meridional direction. Water streams located in the north move clockwise, in the south - against it.

A striking example of the flow of the Atlantic Ocean is the Gulf Stream, which, starting in the Caribbean Sea, carries warm waters to the north, breaking up into several side streams along the way. When the waters of the Gulf Stream end up in the Barents Sea, they enter the Arctic Ocean, where they cool and turn south in the form of a cold Greenland current, after which at some stage they deviate to the west and again adjoin the Gulf Stream, forming a vicious circle.

The currents of the Pacific Ocean are mainly latitudinal and form two huge circles: northern and southern. Since the Pacific Ocean is extremely large, it is not surprising that its water flows have a significant impact on most of our planet.

For example, trade winds move warm water from the western tropical coasts to the eastern ones, which is why the western part of the Pacific Ocean in the tropical zone is much warmer than the opposite side. But in the temperate latitudes of the Pacific Ocean, on the contrary, the temperature is higher in the east.

deep currents

For quite a long time, scientists believed that the deep ocean waters were almost motionless. But soon, special underwater vehicles discovered both slow and fast-flowing water flows at great depths.

For example, under the Equatorial Pacific Ocean at a depth of about one hundred meters, scientists have identified the Cromwell underwater stream moving eastward at a speed of 112 km / day.

A similar movement of water flows, but already in the Atlantic Ocean, was found by Soviet scientists: the width of the Lomonosov current is about 322 km, and the maximum speed of 90 km / day was recorded at a depth of about one hundred meters. After that, another underwater stream was discovered in the Indian Ocean, however, its speed turned out to be much lower - about 45 km / day.

The discovery of these currents in the ocean gave rise to new theories and mysteries, the main of which is the question of why they appeared, how they formed, and whether the entire area of ​​the ocean is covered by currents or there is a point where the water is still.

The influence of the ocean on the life of the planet

The role of ocean currents in the life of our planet cannot be overestimated, since the movement of water flows directly affects the planet's climate, weather, and marine organisms. Many compare the ocean to a huge heat engine powered by solar energy. This machine creates a continuous water exchange between the surface and deep layers of the ocean, providing it with oxygen dissolved in water and affecting the life of marine life.

This process can be traced, for example, by considering the Peruvian Current, which is located in the Pacific Ocean. Thanks to the rise of deep waters, which lift phosphorus and nitrogen upward, animal and plant plankton successfully develop on the ocean surface, as a result of which the food chain is organized. Plankton is eaten by small fish, which, in turn, becomes a victim of larger fish, birds, marine mammals, which, with such food abundance, settle here, making the region one of the most highly productive areas of the World Ocean.

It also happens that a cold current becomes warm: the average ambient temperature rises by several degrees, which causes warm tropical showers to fall on the ground, which, once in the ocean, kill fish accustomed to cold temperatures. The result is deplorable - a huge amount of dead small fish ends up in the ocean, large fish leave, fishing stops, birds leave their nests. As a result, the local population is deprived of fish, crops that were beaten by downpours, and profits from the sale of guano (bird droppings) as fertilizer. It can often take several years to restore the former ecosystem.