5 warm currents. Warm and cold currents

The Atlantic Ocean, or Atlantic, is the second largest (after the Pacific) and the most developed among other water areas. In the east it is limited by the coasts of South and North America, in the west - Africa and Europe, in the north - Greenland, in the south it merges with the Southern Ocean.

Distinctive features of the Atlantic: a small number of islands, complex bottom topography and a highly indented coastline.

Characteristics of the ocean

Area: 91.66 million sq. km, with 16% of the territory falling on seas and bays.

Volume: 329.66 million sq. km

Salinity: 35‰.

Depth: average - 3736 m, greatest - 8742 m (Puerto Rico Trench).

Temperature: in the very south and north - about 0°C, at the equator - 26-28°C.

Currents: conventionally there are 2 gyres - Northern (currents move clockwise) and Southern (counterclockwise). The gyres are separated by the Equatorial Intertrade Current.

Main currents of the Atlantic Ocean

Warm:

Northern trade wind - begins off the west coast of Africa, crosses the ocean from east to west and meets the Gulf Stream near Cuba.

Gulf Stream- the most powerful current in the world, which carries 140 million cubic meters of water per second (for comparison: all the rivers of the world carry only 1 million cubic meters of water per second). It originates near the coast of the Bahamas, where the Florida and Antilles currents meet. Having united, they give rise to the Gulf Stream, which flows into the Atlantic Ocean through the strait between Cuba and the Florida Peninsula. The current then moves north along the US coast. Approximately off the coast of North Carolina, the Gulf Stream turns east and enters the open ocean. After approximately 1,500 km, it meets the cold Labrador Current, which slightly changes the course of the Gulf Stream and carries it to the northeast. Closer to Europe, the current splits into two branches: Azores and North Atlantic.

Only recently it became known that 2 km below the Gulf Stream there is a reverse current flowing from Greenland to the Sargasso Sea. This flow of icy water was called the Anti-Gulf Stream.

North Atlantic- a continuation of the Gulf Stream, which washes the western coast of Europe and brings the warmth of southern latitudes, providing a mild and warm climate.

Antilles- begins east of the island of Puerto Rico, flows north and joins the Gulf Stream near the Bahamas. Speed ​​- 1-1.9 km/h, water temperature 25-28°C.

Interpass countercurrent - current that encircles the globe at the equator. In the Atlantic, it separates the North Trade Wind and South Trade Wind Currents.

South Passat (or South Equatorial) - passes through the southern tropics. The average water temperature is 30°C. When the South Trade Wind Current reaches the coast of South America, it divides into two branches: Caribbean, or Guiana (flows north to the coast of Mexico) and Brazilian— moving south along the coast of Brazil.

Guinean - located in the Gulf of Guinea. It flows from west to east and then turns south. Together with the Angolan and South Equatorial currents, it forms the cyclic current of the Gulf of Guinea.

Cold:

Lomonosov countercurrent - discovered by a Soviet expedition in 1959. It originates off the coast of Brazil and moves north. The 200 km wide stream crosses the equator and flows into the Gulf of Guinea.

Canary- flows from north to south, towards the equator along the coast of Africa. This wide stream (up to 1 thousand km) near Madeira and the Canary Islands meets the Azores and Portuguese currents. Approximately around 15°N latitude. joins the Equatorial Countercurrent.

Labrador - begins in the strait between Canada and Greenland. It flows south to the Newfoundland Bank, where it meets the Gulf Stream. The waters of the current carry cold from the Arctic Ocean, and along with the flow, huge icebergs are carried south. In particular, the iceberg that destroyed the famous Titanic was brought precisely by the Labrador Current.

Benguela- is born near the Cape of Good Hope and moves along the coast of Africa to the north.

Falkland (or Malvinas) branches off from the West Wind Current and flows north along the east coast of South America to the Gulf of La Plata. Temperature: 4-15°C.

Current of the westerly winds encircles the globe in the region of 40-50°S. The flow moves from west to east. In the Atlantic it branches off South Atlantic flow.

Underwater world of the Atlantic Ocean

The underwater world of the Atlantic is poorer in diversity than in the Pacific Ocean. This is due to the fact that the Atlantic Ocean was more exposed to freezing during the Ice Age. But the Atlantic is richer in the number of individuals of each species.

The flora and fauna of the underwater world is clearly distributed among climatic zones.

The flora is represented mainly by algae and flowering plants (Zostera, Poseidonia, Fucus). In northern latitudes, kelp predominates; in temperate latitudes, red algae predominates. Throughout the ocean, phytoplankton actively thrives at depths of up to 100 m.

The fauna is rich in species. Almost all species and classes of marine animals live in the Atlantic. Of the commercial fish, herring, sardine, and flounder are especially valued. There is an active catch of crustaceans and mollusks, and whaling is limited.

The tropical zone of the Atlantic amazes with its abundance. There are a lot of corals and many amazing species of animals: turtles, flying fish, several dozen species of sharks.

The name of the ocean first appears in the works of Herodotus (5th century BC), who calls it the Sea of ​​Atlantis. And in the 1st century AD. The Roman scientist Pliny the Elder writes about a vast expanse of water called Oceanus Atlanticus. But the official name “Atlantic Ocean” was established only in the 17th century.

The history of Atlantic exploration can be divided into 4 stages:

1. From antiquity to the 15th century. The first documents that talk about the ocean date back to the 1st millennium BC. The ancient Phoenicians, Egyptians, Cretans and Greeks knew the coastal zones of the water area well. Maps of those times have been preserved with detailed depth measurements and indications of currents.

2. The time of the Great Geographical Discoveries (XV-XVII centuries). The development of the Atlantic continues, the ocean becomes one of the main trade routes. In 1498, Vasco de Gama, having circumnavigated Africa, paved the way to India. 1493-1501 - Columbus's three voyages to America. The Bermuda anomaly was identified, many currents were discovered, detailed maps of depths, coastal zones, temperatures, and bottom topography were compiled.

Expeditions of Franklin in 1770, I. Kruzenshtern and Yu. Lisyansky of 1804-06.

3. XIX - first half of the XX century - the beginning of scientific oceanographic research. Chemistry, physics, biology, ocean geology are studied. A map of currents has been compiled, and research is being carried out to lay an underwater cable between Europe and America.

4. 1950s - present day. A comprehensive study of all components of oceanography is being carried out. Priorities include: studying the climate of different zones, identifying global atmospheric problems, ecology, mining, ensuring ship traffic, and seafood production.

In the center of the Belize Barrier Reef there is a unique underwater cave - the Great Blue Hole. Its depth is 120 meters, and at the very bottom there is a whole gallery of smaller caves connected by tunnels.

The Atlantic is home to the only sea in the world without shores - the Sargasso. Its boundaries are formed by ocean currents.

Here is one of the most mysterious places on the planet: the Bermuda Triangle. The Atlantic Ocean is also home to another myth (or reality?) - the continent of Atlantis.

Is the Gulf Stream, El Niño, Kuroshio. What other currents exist? Why are they called warm? Read about it further.

Where do currents come from?

Currents are directional flows of water masses. They can have different widths and depths - from several meters to hundreds of kilometers. Their speed can reach up to 9 km/h. The direction of water flows is determined by the rotational force of our planet. Thanks to it, currents in the Southern Hemisphere deviate to the right, and in the Northern Hemisphere - to the left.

The formation and character of currents is influenced by many conditions. The reason for their appearance may be the wind, the tidal forces of the Moon and the Sun, different densities and temperatures, and the water level of the World Ocean. Most often, several factors contribute to the formation of currents.

There is a neutral, in the ocean. They are defined as such not because of the temperature of their own water masses, but because of the difference with the temperature of the surrounding waters. This means that the current can be warm, even if its waters are considered cold by many indicators. For example, the Gulf Stream is warm, although its temperature ranges from 4 to 6 degrees, and the cold temperature is up to 20 degrees.

A warm current is one that forms near the equator. They form in warm waters and move to colder ones. In turn, they move towards the equator. Neutral currents are those that do not differ in temperature from the surrounding waters.

Warm currents

Currents influence the climate of coastal areas. Warm water currents warm the ocean waters. They contribute to a mild climate, high air humidity and large amounts of precipitation. Forests form on the banks next to which warm waters flow. There are such warm currents of the World Ocean:

Pacific Ocean Basin

• East Australian.
• Alaskan.
• Kuroshio.
• El Niño.

Indian Ocean Basin

• Agulhasskoe.

Atlantic Ocean Basin

• Irminger.
• Brazilian.
• Guiana.
• Gulf Stream.
• North Atlantic.

Arctic Ocean Basin

• West Spitsbergen.
• Norwegian.
• West Greenland.

Gulf Stream

The warm Atlantic current, one of the largest in the Northern Hemisphere, is the Gulf Stream. It begins in the waters of the Atlantic Ocean and moves in a northeast direction.

The current carries a lot of floating algae and various fish. Its width reaches up to 90 kilometers, and the temperature is 4-6 degrees Celsius. The waters of the Gulf Stream have a bluish tint, contrasting with the surrounding greenish ocean water. It is not homogeneous, and consists of several streams that can separate from the general flow.

The Gulf Stream is a warm current. Meeting with the cold Labrador Current in the Newfoundland area, it contributes to the frequent formation of fogs along the coast. In the very center of the North Atlantic, the Gulf Stream divides, forming the Canary and North Atlantic currents.

El Niño

El Niño is also a warm current - the most powerful current. It is not constant and occurs once every few years. Its appearance is accompanied by a sharp increase in water temperature in the surface layers of the ocean. But this is not the only sign of El Niño.

Other warm currents of the World Ocean can hardly compare with the power of influence of this “baby” (as the name of the current is translated). Together with warm waters, the current brings with it strong winds and hurricanes, fires, droughts, and prolonged rains. Residents of coastal areas are suffering from the damage caused by El Niño. Vast areas are flooded, leading to the destruction of crops and livestock.

The current is formed in the Pacific Ocean, in its equatorial part. It stretches along the coast of Peru and Chile, replacing the cold Humboldt Current. When El Niño occurs, fishermen also suffer. Its warm waters trap cold waters (which are rich in plankton) and prevent them from rising to the surface. In this case, the fish do not come to these territories to feed, leaving fishermen without a catch.

Kuroshio

In the Pacific Ocean, another warm current is the Kuroshio. It flows near the eastern and southern coasts of Japan. The current is often defined as a continuation of the Northern Trade Wind. The main reason for its formation is the difference in levels between the ocean and the East China Sea.

Flowing between the straits of Ryukkyu Island, the Kuroshio becomes the North Pacific Current, which turns into the Alaskan Current off the coast of America.

It has similar features to the Gulf Stream. It forms a whole system of warm currents in the Pacific Ocean, just like the Gulf Stream in the Atlantic. Thanks to this, Kuroshio is an important climate-forming factor, softening the climate of coastal areas. The current also has a strong influence on the water area, being an important hydrobiological factor.

The waters of the Japanese current are characterized by a dark blue color, hence its name “Kuroshio”, which translates as “black current” or “dark water”. The current reaches a width of 170 kilometers, and its depth is about 700 meters. Kuroshio's speed ranges from 1 to 6 km/h. The water temperature of the current is 25 -28 degrees in the south and approximately 15 degrees in the north.

Conclusion

The formation of currents is influenced by many factors, and sometimes a combination of them. A current whose temperature exceeds the temperature of the surrounding waters is called warm. At the same time, the water in the current can be quite cold. The most famous warm currents are the Gulf Stream, which flows in the Atlantic Ocean, as well as the Pacific Kuroshio and El Niño currents. The latter occurs periodically, bringing with it a chain of environmental disasters.

As a rule, their movement occurs in a strictly defined direction and can have a large extent. The current map below displays them in full.

Water flows are of considerable size: they can reach tens, or even hundreds of kilometers in width, and have great depth (hundreds of meters). The speed of ocean and sea currents varies - on average, it is 1-3 thousand m/hour. But there are also so-called high-speed ones. Their speed can reach 9,000 m/hour.

Where do currents come from?

The causes of water currents can be a sharp change in water temperature due to heating, or, conversely, cooling. They are also affected by different densities, for example, in a place where several currents (sea and ocean) collide, precipitation, evaporation. But basically, cold and warm currents arise due to the action of winds. Therefore, the direction of the largest oceanic water flows depends mainly on the air currents of the planet.

Currents formed by winds

An example of constantly blowing winds is the trade winds. They begin their life from 30 latitudes. The currents created by these air masses are called trade winds. There are the Southern Trade Wind and Northern Trade Wind Currents. In the temperate zone, such water flows are formed under the influence of westerly winds. They form one of the largest currents on the planet. In the northern and southern hemispheres there are two water flow cycles: cyclonic and anticyclonic. Their formation is influenced by the inertial force of the Earth.

Types of currents

Mixed, neutral, cold and warm currents are types of circulating masses on the planet. When the temperature of the stream water is lower than the temperature of the surrounding water, this is If, on the contrary, this is its warm variety. Neutral currents do not differ from the temperature of surrounding waters. And mixed ones can change along their entire length. It is worth noting that there is no constant temperature indicator for currents. This figure is very relative. It is determined by comparing the surrounding water masses.

In tropical latitudes, warm currents circulate along the eastern edges of the continents. Cold ones - along the western ones. In temperate latitudes, warm currents pass along the western shores, and cold currents along the eastern shores. The variety can be determined by another factor. So, there is an easier rule: cold currents go towards the equator, and warm currents - from it.

Meaning

It’s worth talking about it in more detail. Cold and warm currents play an important role on planet Earth. The significance of circulating water masses is that due to their movement, solar heat is redistributed on the planet. Warm currents increase the air temperature of nearby areas, while cold currents lower it. Formed on water, water flows have a serious impact on the mainland. In areas where warm currents constantly pass, the climate is humid, where there are cold currents, on the contrary, it is dry. Ocean currents also contribute to the migration of oceanic ichthyofauna. Under their influence, plankton moves, and fish migrate after them.

We can give examples of warm and cold currents. Let's start with the first variety. The largest water flows are: Gulf Stream, Norwegian, North Atlantic, Northern and Southern Trade Winds, Brazilian, Kuroshio, Madagascar and others. The coldest ocean currents: Somali, Labrador, California.

Major currents

The largest warm current on the planet is the Gulf Stream. This is a meridional circulating flow that carries 75 million tons of water every second. The width of the Gulf Stream is from 70 to 90 km. Thanks to him, Europe receives a comfortable mild climate. It follows from this that cold and warm currents largely affect the life of all living organisms on the planet.

Of the zonal, cold watercourses, the current is of greatest importance. In the southern hemisphere, near the shores of Antarctica, there are no island or continental accumulations. A large area of ​​the planet is completely filled with water. The Indian and Quiet streams converge here into one stream and unite into a separate huge body of water. Some scientists recognize its existence and call it Southern. It is here that the largest flow of water is formed - the current of the Western Winds. Every second it carries a flow of water that is three times larger than the Gulf Stream.

Canary or cold?

Currents can change their temperature. For example, the flow starts from cold masses. Then it warms up and becomes warm. One of the options for such a circulating water mass is the Canary Current. It originates in the northeast Atlantic Ocean. It is directed by a cold stream along Europe. Passing along the western coast of Africa, it becomes warm. This current has long been used by sailors to travel.

The world's oceans are an incredibly complex, multifaceted system that has not been fully studied to date. Water in large water basins should not be stationary, as this would quickly lead to a large-scale environmental disaster. One of the most important factors in maintaining balance on the planet is the currents of the World Ocean.

Reasons for the formation of currents

An ocean current is a periodic or, on the contrary, constant movement of impressive volumes of water. Very often, currents are compared to rivers, which exist according to their own laws. Water circulation, its temperature, power and flow speed - all these factors are determined by external influences.

The main characteristics of ocean currents are direction and speed.

The circulation of water flows in the World Ocean occurs under the influence of physical and chemical factors. These include:

• Wind. Under the influence of strong air currents, water moves on the surface of the ocean and at its shallow depths. The wind has no effect on deep-sea currents.
• Space. The influence of cosmic bodies (Sun, Moon), as well as the rotation of the Earth in orbit and around its axis leads to the displacement of layers of water in the World Ocean.
• Different indicators of water density- what determines the appearance of ocean currents.

Rice. 1. The formation of currents largely depends on the influence of space.

Direction of currents

Depending on the direction of water flows, they are divided into 2 types:

• Zonal- moving to the East or West.
• Meridional- directed to the North or South.

There are other types of currents, the appearance of which is caused by ebbs and flows. They are called tidal, and they are most powerful in the coastal zone.

TOP 3 articleswho are reading along with this

Sustainable are called currents in which the strength of the flow and its direction remain unchanged. These include the Southern Trade Wind and Northern Trade Wind Currents.

If the flow changes, then it is called unstable. This group includes all surface currents.

Our ancestors have known about the existence of currents since time immemorial. During shipwrecks, sailors threw corked bottles into the water with notes containing the coordinates of the incident, requests for help, or words of farewell. They knew for sure that sooner or later their messages would reach people precisely thanks to currents.

Warm and cold currents of the World Ocean

The formation and maintenance of climate on the globe is greatly influenced by ocean currents, which, depending on the temperature of the water, can be warm or cold.

Water streams whose temperature is above 0 are called warm.

These include the Gulf Stream, Kuroshio, Alaskan and others. They usually move from low to high latitudes.

The warmest current in the world's oceans is El Niño, whose name means Christ Child in Spanish. And this is not without reason, since a strong and full of surprises current appears on the globe on Christmas Eve.

Fig.2. El Niño is the warmest current.

Cold currents have a different direction of movement, the largest of which are the Peruvian and Californian.

The division of ocean currents into cold and warm is very arbitrary, since it shows the ratio of the temperature of the water in the flow to the temperature of the surrounding water. For example, if the water in the flow is warmer than in the surrounding water space, then such a flow is called thermal, and vice versa.

4.3. Total ratings received: 262.