Why is the Caspian Sea called. The seas of Russia are the Caspian Sea. Shipping is developed in the Caspian Sea. Ferry crossings operate on the Caspian Sea, in particular, Baku - Turkmenbashi, Baku - Aktau, Makhachkala - Aktau. The Caspian Sea has a navigable

The Caspian Sea is located in different geographical zones. It plays a big role in world history, is an important economic region and source of resources. The Caspian Sea is a unique body of water.

Short description

This sea has big sizes. The bottom is covered with oceanic bark. These factors make it possible to classify it as a sea.

It is a closed reservoir, has no drains and is not connected with the waters of the oceans. Therefore, it can also be attributed to the category of lakes. In this case, it will be the most big lake on the planet.

The approximate area of ​​the Caspian Sea is about 370 thousand square kilometers. The volume of the sea changes depending on the various fluctuations in the water level. The average value is 80 thousand cubic kilometers. The depth varies in its parts: the southern one has a greater depth than the northern one. The average depth is 208 meters, the highest value in the southern part exceeds 1000 meters.

The Caspian Sea plays an important role in the development of trade relations between the countries. The resources mined in it, as well as other trade items, were transported to different countries since the development of navigation at sea. Since the Middle Ages, merchants have delivered exotic goods, spices and furs. Today, in addition to the transportation of resources, by sea, ferry crossings between cities. The Caspian Sea is also connected by a navigable canal through rivers with Sea of ​​Azov.

Geographic characteristics

The Caspian Sea is located between two continents - Europe and Asia. Washes the territory of several countries. These are Russia, Kazakhstan, Iran, Turkmenistan and Azerbaijan.

It has more than 50 islands, both large and small in size. For example, the islands of Ashur-Ada, Tyuleniy, Chigil, Gum, Zenbil. As well as the peninsulas, the most significant - Absheron, Mangyshlak, Agrakhan and others.

Main tributary water resources The Caspian Sea receives from the rivers flowing into it. In total, there are 130 tributaries of this reservoir. The largest is the Volga River, which brings the bulk of the water. The Kheras, Ural, Terek, Astarchay, Kura, Sulak and many others rivers also flow into it.

The waters of this sea form many bays. Among the largest are: Agrakhansky, Kizlyarsky, Turkmenbashi, Girkan Bay. In the eastern part there is a bay-lake called Kara-Bogaz-Gol. It communicates with the sea by a small strait.

Climate

The climate is characterized geographical location sea, therefore, it has several types: from continental in the northern region to subtropical in the south. This affects the air and water temperatures, which have great contrasts depending on the part of the sea, especially in the cold season.

in winter average temperature air in the northern region is about -10 degrees, water reaches a value of -1 degree.

In the southern region, the temperature of air and water in winter warms up to an average of +10 degrees.

IN summer time The air temperature in the northern zone reaches +25 degrees. Much hotter in the south. The maximum recorded value here is + 44 degrees.

Resources

The natural resources of the Caspian Sea contain large reserves of various deposits.

One of the most valuable resources of the Caspian Sea is oil. Mining has been carried out since about 1820. Springs were opened on the territory of the seabed and its coast. By the beginning of the new century, the Caspian was at the forefront in obtaining this valuable product. During this time, thousands of wells were opened, which made it possible to extract oil on a huge industrial scale.

The Caspian Sea and the territory adjacent to it also have rich deposits of natural gas, mineral salts, sand, lime, several types of natural clay and rocks.

Inhabitants and fisheries

The biological resources of the Caspian Sea are very diverse and highly productive. It contains more than 1500 species of inhabitants, rich in commercial fish species. The population depends on climatic conditions in different parts of the sea.

In the northern part of the sea, pike perch, bream, catfish, asp, pike and other species are more common. Gobies, mullet, bream, herring live in the western and eastern. southern waters rich various representatives. One of the many are sturgeons. According to their content, this sea occupies a leading place among other reservoirs.

Among the wide variety, tuna, beluga, stellate sturgeon, sprat and many others are also caught. In addition, there are mollusks, crayfish, echinoderms and jellyfish.

The mammal Caspian seal lives in the Caspian Sea, or This animal is unique and lives only in these waters.

The sea is also characterized by a high content of various algae, for example, blue-green, red, brown; sea ​​grass and phytoplankton.

Ecology

The extraction and transportation of oil has a huge negative impact on the ecological situation of the sea. The ingress of oil products into water is almost inevitable. Oil stains cause irreparable damage to marine habitats.

The main inflow of water resources to the Caspian Sea is provided by rivers. Unfortunately, most of them have a high level of pollution, which degrades the quality of the water in the sea.

Industrial and domestic effluents from the surrounding cities are poured into the sea in large quantities, which also damages the environment.

Poaching causes great damage to the marine habitat. Sturgeon species are the main target for illegal catching. This significantly reduces the number of sturgeon and threatens the entire population of this type.

The above information will help to assess the resources of the Caspian Sea, to briefly study the characteristics and ecological situation of this unique reservoir.

The Caspian Sea is the most big lake On the Earth. It is called the sea because of its size and bed, which is folded like an ocean basin. The area is 371,000 square meters, the depth is 1025 m. The list of rivers flowing into the Caspian Sea includes 130 names. The largest of them are: Volga, Terek, Samur, Sulak, Ural and others.

Caspian Sea

It took 10 million years before the Caspian was formed. The reason for its formation is that the Sarmatian Sea, which lost its connection with the World Ocean, was divided into two reservoirs, which were called the Black and Caspian Seas. Between the latter and the World Ocean stretch thousands of kilometers of waterless path. It is located at the junction of two continents - Asia and Europe. Its length in the north-south direction is 1200 km, west-east - 195-435 km. The Caspian Sea is an internal drainless basin of Eurasia.

Near the Caspian Sea, the water level is below the level of the World Ocean, and besides, it is subject to fluctuations. According to scientists, this is due to many factors: anthropogenic, geological, climatic. At present, the average water level reaches 28 m.

The network of rivers and sewage is unevenly distributed along the coast. To the part of the sea with north side Few rivers flow into it: Volga, Terek, Ural. From the west - Samur, Sulak, Kura. The east coast is characterized by the absence of permanent watercourses. Differences in space in the flow of water that rivers bring to the Caspian Sea is an important geographical feature of this reservoir.

Volga

This river is one of the largest in Europe. In Russia, it ranks sixth in size. In terms of catchment area, it is second only to Siberian rivers flowing into the Caspian Sea, such as the Ob, Lena, Yenisei, Irtysh. For the source, from where the Volga originates, the key is taken near the village of Volgoverkhovye, Tver Region, on the Valdai Upland. Now there is a chapel at the source, which attracts the attention of tourists, for whom it is a pride to step over the very beginning of the mighty Volga.

A small fast stream gradually gains strength and becomes a huge river. Its length is 3690 km. The source is 225 m above sea level. Among the rivers flowing into the Caspian Sea, the largest is the Volga. Her path runs through many regions of our country: Tver, Moscow, Nizhny Novgorod, Volgograd and others. The territories through which it flows are Tatarstan, Chuvashia, Kalmykia and Mari El. The Volga is the location of millionaire cities - Nizhny Novgorod, Samara, Kazan, Volgograd.

Volga Delta

The main riverbed is divided into channels. Formed certain form mouth. It's called the delta. Its beginning is the place of separation of the Buzan branch from the bed of the Volga river. The delta is located 46 km north of the city of Astrakhan. It includes channels, branches, small rivers. There are several main branches, but only Akhtuba is navigable. Among all the rivers of Europe, the Volga is distinguished by the largest delta, which is a rich fish region in this basin.

It lies 28 m lower than the ocean level. The mouth of the Volga is the location of the southernmost Volga city of Astrakhan, which in the distant past was the capital of the Tatar Khanate. Later, at the beginning of the 18th century (1717), Peter 1 gave the city the status of "the capital of the province of Astrakhan." During his reign, the main attraction of the city, the Assumption Cathedral, was built. Its Kremlin is made of white stone, brought from the capital of the Golden Horde, the city of Saray. The mouth is divided by branches, the largest of which are: Bolda, Bakhtemir, Buzan. Astrakhan is a southern city located on 11 islands. Today it is a city of shipbuilders, sailors and fishermen.

Currently, the Volga needs protection. For this purpose, a reserve has been established at the place where the river flows into the sea. The delta of the Volga, the largest river flowing into the Caspian Sea, abounds unique flora and fauna: sturgeon, lotuses, pelicans, flamingos and others. Immediately after the revolution of 1917, a law was passed on their protection by the state as part of the Astrakhan Reserve.

Sulak River

It is located in Dagestan, flows through its territory. It feeds on the waters of melted snows that flow down from the mountains, as well as tributaries: Small Sulak, Chvakhun-bak, Akh-su. Water also enters Sulak through a canal from the Aksai and Aktash rivers.

The source is formed by the confluence of two rivers that originate in the basins: Didoyskaya and Tushinskaya. The length of the Sulak River is 144 km. Its pool has a fairly large area - 15,200 square meters. It flows through the canyon with the same name as the river, then through the Akhetlinsky gorge and finally comes to the plane. Going around the Agrakhan Bay with south side, Sulak flows into the sea.

The river provides drinking water to Kaspiysk and Makhachkala, it is home to hydroelectric power plants, the urban-type settlements of Sulak and Dubki, and small town Kizilyurt.

Samur

The river got its name not by chance. The name translated from the Caucasian language (one of them) means "middle". Indeed, the border between the states of Russia and Azerbaijan is marked along the waterway along the Samur River.

The sources of the river are glaciers and springs, originating in the spurs of the Caucasus Range from the northeast side, not far from the Guton mountain. The height above sea level is 3200 m. Samur has a length of 213 km. The height in the upper reaches and the mouth differs by three kilometers. The catchment basin has an area of ​​almost five thousand square meters.

The places where the river flows are narrow gorges located between the mountains. high altitude, composed of shale and sandstone, which is why the water here is muddy. The Samur basin has 65 rivers. Their length reaches 10 km or more.

Samur: the valley and its description

The valley of this river in Dagestan is the most densely populated region. Derbent is located near the mouth - ancient city peace. The banks of the Samur River are home to twenty or more species of relict representatives of the flora. Endemic, endangered and rare species listed in the Red Book grow here.

In the river delta, a relict forest is comfortably located, which is the only one in Russia. Liana forest is a fairy tale. Huge trees of the rarest and most common species grow here, intertwined with lianas. The river is rich in valuable species of fish: mullet, pike perch, pike, catfish and others.

Terek

The river got its name from the Karachay-Balkar peoples who lived along its banks. They called it "Terk Suu", which means "rushing water" in translation. Ingush and Chechens called it Lomeki - "mountain water".

The beginning of the river is the territory of Georgia, the Zigla-Khokh glacier is a mountain located on a slope Caucasian ridge. It is under glaciers all year round. One of them melts when sliding down. A small stream is formed, which is the source of the Terek. It is located at an altitude of 2713 m above sea level. The length of the river flowing into the Caspian Sea is 600 km. At the confluence with the Caspian, the Terek is divided into many branches, as a result of which a vast delta is formed, its area is 4000 square meters. In some places it is very swampy.

The course in this place has changed several times. The old arms have now been turned into canals. The middle of the last century (1957) was marked by the construction of the Kargaly hydroelectric complex. It is used to supply water to the channels.

How is the Terek replenished?

The river has a mixed supply, but for the upper reaches, water from the melting of glaciers plays an important role, they fill the river. In this regard, 70% of the runoff occurs in spring and summer, that is, at this time the water level in the Terek is the highest, and the lowest is in February. The river freezes if the winters are characterized by a harsh climate, but the freeze-up is unstable.

The river is not distinguished by cleanliness and transparency. The turbidity of the water is large: 400-500 g/m 3 . Every year, the Terek and its tributaries pollute the Caspian Sea, pouring into it from 9 to 26 million tons of various suspensions. This is due to the rocks of which the shores are composed, and they are clayey.

Terek mouth

Sunzha is the most major tributary, flowing into the Terek, the lower reaches of which are counted precisely from this river. By this time, the Terek flows for a long time over the flat terrain, leaving the mountains located behind the Elkhot Gates. The bottom here is composed of sand and pebbles, the current slows down, and in some places stops altogether.

The mouth of the Terek River has an unusual appearance: the channel here is elevated above the valley, along appearance resembles a canal, which is fenced with an embankment of great height. The water level rises above the land level. This phenomenon is due to a natural cause. Since the Terek is a turbulent river, it brings sand and stones in large quantities from the Caucasus Range. Given that the current in the lower reaches is weak, some of them settle here and do not reach the sea. For the inhabitants of the area, sediments are both a threat and a boon. When they are washed away by water, floods of great destructive power occur, this is very bad. But in the absence of floods, the soils become fertile.

Ural River

In ancient times (until the second half of the 18th century), the river was called Yaik. It was renamed into the Russian style by the decree of Catherine II in 1775. Just at this time, the Peasant War was suppressed, the leader of which was Pugachev. The name is still preserved in the Bashkir language, and in Kazakhstan it is official. The Urals are the third longest in Europe, only the Volga and the Danube are larger than this river.

The Ural originates in Russia, on the slope of the Kruglyaya Sopka of the Uraltau Ridge. The source is a spring gushing out of the ground at an altitude of 637 m above sea level. At the beginning of its journey, the river flows in a north-south direction, but after meeting a plateau on the way, it makes a sharp turn and continues to flow in a north-westerly direction. However, beyond Orenburg, its direction again changes to the southwestern, which is considered the main one. Having overcome the winding path, the Ural flows into the Caspian Sea. The length of the river is 2428 km. The mouth is divided into branches and tends to shallow.

The Ural is a river along which the natural water boundary between Europe and Asia passes, with the exception of the upper reaches. This is an inland European river, but its upper reaches east of Ural Range are the territory of Asia.

Importance of the Caspian rivers

The rivers flowing into the Caspian Sea are of great importance. Their waters are used for human and animal consumption, domestic needs, agricultural and industrial needs. Hydroelectric power plants are being built on the rivers, the energy of which is in demand by man for various purposes. River basins are full of fish, algae, shellfish. Even in ancient times, people chose river valleys for future settlements. And now cities and towns are being built on their banks. Rivers ply passenger and transport ships, performing important tasks for the transport of passengers and goods.

The Caspian Sea is the largest lake on Earth, located at the junction of Europe and Asia, called the sea because of its size. The Caspian Sea is drainless lake, and the water in it is salty, from 0.05 ‰ near the mouth of the Volga to from 11-13 ‰ in the southeast. The water level is subject to fluctuations, currently - about -28 m below the level of the World Ocean. The area of ​​the Caspian Sea is currently approximately 371,000 km², maximum depth- 1025 m.

The Caspian Sea is located at the junction of two parts of the Eurasian continent - Europe and Asia. The Caspian Sea is similar in shape to latin letter S, the length of the Caspian Sea from north to south is approximately 1200 kilometers (36°34′ - 47°13′ N), from west to east - from 195 to 435 kilometers, on average 310-320 kilometers (46° - 56° E).

The Caspian Sea is conditionally divided according to physical and geographical conditions into 3 parts - the Northern Caspian, the Middle Caspian and the Southern Caspian. The conditional border between the North and Middle Caspian is passed along the line Chechen (island) - Tyub-Karagansky cape, between the Middle and South Caspian - along the line Zhiloy (island) - Gan-Gulu (cape). The area of ​​the Northern, Middle and Southern Caspian is 25, 36, 39 percent respectively.

Origin

According to one of the hypotheses, the Caspian Sea got its name in honor of the ancient tribes of horse breeders - the Caspians, who lived before our era on the southwestern coast of the Caspian Sea. Throughout the history of its existence, the Caspian Sea had about 70 names for different tribes and peoples: the Hyrcanian Sea; The Khvalyn Sea or the Khvalis Sea is an ancient Russian name, derived from the name of the inhabitants of Khorezm, who traded in the Caspian Sea - Khvalis; Khazar Sea - the name in Arabic (Bahr-al-Khazar), Persian (Daria-e Khazar), Turkish and Azerbaijani (Khazar Denizi) languages; Abeskun Sea; Saray Sea; Derbent Sea; Sihai and other names. In Iran, the Caspian Sea is still called the Khazar or Mazenderan Sea (after the name of the people inhabiting the Iranian coastal province of the same name).

Data

The coastline of the Caspian Sea is estimated at about 6500 - 6700 kilometers, with islands - up to 7000 kilometers. The shores of the Caspian Sea in most of its territory are low-lying and smooth. In the northern part, the coastline is indented by water streams and islands of the Volga and Ural deltas, the shores are low and swampy, and the water surface is covered with thickets in many places. On east coast limestone coasts adjoining semi-deserts and deserts predominate. The most winding coasts are on the west coast in the area of ​​the Apsheron Peninsula and on the east coast in the area of ​​the Kazakh Gulf and Kara-Bogaz-Gol.

Islands

Large peninsulas Caspian Sea: Agrakhan Peninsula, Absheron Peninsula, Buzachi, Mangyshlak, Miankale, Tub-Karagan.

There are about 50 large and medium-sized islands in the Caspian Sea with total area approximately 350 square kilometers. Most major islands: Ashur-Ada, Garasu, Gum, Dash, Zira (island), Zyanbil, Kyur Dashy, Khara-Zira, Sengi-Mugan, Chechen (island), Chygyl.

gulfs

Large bays Caspian Sea: Agrakhansky Gulf, Komsomolets (Gulf) (former Dead Kultuk, former Tsesarevich Gulf), Kaydak, Mangyshlak, Kazakh (Gulf), Turkmenbashi (Gulf) (former Krasnovodsk), Turkmen (Gulf), Gyzylagach, Astrakhan (Gulf) , Gizlar, Girkan (former Astarabad) and Enzali (former Pahlavi).

nearby lakes

Off the east coast is salt Lake Kara Bogaz Gol, until 1980 it was a bay-lagoon of the Caspian Sea, connected to it by a narrow strait. In 1980, a dam was built separating Kara-Bogaz-Gol from the Caspian Sea, in 1984 a culvert was built, after which the level of Kara-Bogaz-Gol dropped by several meters. In 1992, the strait was restored, through which water leaves the Caspian Sea to Kara-Bogaz-Gol and evaporates there. Every year, 8-10 cubic kilometers of water (according to other sources - 25 thousand kilometers) and about 150 thousand tons of salt enter Kara-Bogaz-Gol from the Caspian Sea.

Rivers

130 rivers flow into the Caspian Sea, of which 9 rivers have a mouth in the form of a delta. Large rivers flowing into the Caspian Sea are the Volga, Terek (Russia), Ural, Emba (Kazakhstan), Kura (Azerbaijan), Samur (Russian border with Azerbaijan), Atrek (Turkmenistan) and others. largest river, which flows into the Caspian Sea - the Volga, its average annual runoff is 215-224 cubic kilometers. The Volga, Ural, Terek and Emba provide up to 88 - 90% of the annual drainage of the Caspian Sea.

Pool

The area of ​​the Caspian Sea basin is approximately 3.1 - 3.5 million square kilometers, which is approximately 10 percent of the world's closed water basins. The length of the Caspian Sea basin from north to south is about 2,500 kilometers, from west to east - about 1,000 kilometers. The Caspian Sea basin covers 9 states - Azerbaijan, Armenia, Georgia, Iran, Kazakhstan, Russia, Uzbekistan, Turkey and Turkmenistan.

Cities and states

The Caspian Sea washes the shores of five coastal states:

Russia (Dagestan, Kalmykia and Astrakhan region) - in the west and north-west, the length of the coastline is 695 kilometers
Kazakhstan - in the north, northeast and east, the length of the coastline is 2320 kilometers
Turkmenistan - in the southeast, the length of the coastline is 1200 kilometers
Iran - in the south, the length of the coastline - 724 kilometers
Azerbaijan - in the southwest, the length of the coastline is 955 kilometers
The largest city - a port on the Caspian Sea - Baku, the capital of Azerbaijan, which is located in the southern part of the Absheron Peninsula and has 2,070 thousand people (2003). Other large Azerbaijani Caspian cities are Sumgayit, which is located in the northern part of the Absheron Peninsula, and Lankaran, which is located near the southern border of Azerbaijan. To the South-East of the Absheron Peninsula, there is a settlement of oil workers Neftyanye Kamni, whose facilities stand on artificial islands, flyovers and technological platforms.

Large Russian cities- the capital of Dagestan, Makhachkala and the southernmost city of Russia, Derbent - are located on the western coast of the Caspian Sea. port city Astrakhan is also considered to be part of the Caspian Sea, which, however, is not located on the shores of the Caspian Sea, but in the Volga delta, 60 kilometers from the northern coast of the Caspian Sea.

On the eastern shore of the Caspian Sea is the Kazakh city - the port of Aktau, in the north in the Ural delta, 20 km from the sea, the city of Atyrau is located, south of Kara-Bogaz-Gol on the northern shore of the Krasnovodsk Bay - the Turkmen city of Turkmenbashi, formerly Krasnovodsk. Several Caspian cities are located on the southern (Iranian) coast, the largest of them is Anzali.

Dimensions

The area and volume of water in the Caspian Sea varies significantly depending on fluctuations in water levels. At a water level of -26.75 m, the area was approximately 392,600 square kilometers, the volume of water was 78,648 cubic kilometers, which is approximately 44 percent of the world's lake water reserves. The maximum depth of the Caspian Sea is in the South Caspian depression, 1025 meters from its surface level. In terms of maximum depth, the Caspian Sea is second only to Baikal (1620 m) and Tanganyika (1435 m). The average depth of the Caspian Sea, calculated from the bathygraphic curve, is 208 meters. At the same time in Northern part The Caspian Sea is shallow, its maximum depth does not exceed 25 meters, and average depth- 4 meters.

The water level in the Caspian Sea is subject to significant fluctuations. According to modern science, over the past 3 thousand years, the amplitude of changes in the water level of the Caspian Sea was 15 meters. Instrumental measurement of the level of the Caspian Sea and systematic observations of its fluctuations have been carried out since 1837, during this time the highest water level was recorded in 1882 (-25.2 m.), the lowest - in 1977 (-29.0 m.) , since 1978 the water level has risen and in 1995 reached -26.7 m, since 1996 there has been a downward trend again. Scientists associate the causes of changes in the water level of the Caspian Sea with climatic, geological and anthropogenic factors.

Climate

Water temperature is subject to significant latitudinal changes, most clearly expressed in winter period when the temperature changes from 0 - 0.5 °C at the ice edge in the north of the sea to 10 - 11 °C in the south, that is, the water temperature difference is about 10 °C. For shallow water areas with depths less than 25 m, the annual amplitude can reach 25 - 26 °C. The average water temperature at west coast 1 - 2 °C higher than that of the eastern, and in the open sea the water temperature is 2 - 4 °C higher than that of the coasts. According to the nature of the horizontal structure of the temperature field in the annual cycle of variability, three time intervals can be distinguished in the upper 2-m layer. From October to March, the water temperature increases in the south and east, which is especially evident in the Middle Caspian. Two stable quasi-latitudinal zones can be distinguished, where the temperature gradients are increased. This is, firstly, the border between the North and Middle Caspian, and, secondly, between the Middle and South. At the ice edge, in the northern frontal zone, the temperature in February-March increases from 0 to 5 °C, in the southern frontal zone, in the area of ​​the Apsheron threshold, from 7 to 10 °C. During this period, the least chilled waters are in the center of the South Caspian, which form a quasi-stationary core. In April-May, the area of ​​minimum temperatures moves to the Middle Caspian, which is associated with faster warming of waters in the shallow northern part of the sea. True, at the beginning of the season in the northern part of the sea a large number of heat is spent on melting ice, but already in May the temperature rises here to 16 - 17 °C. In the middle part, the temperature at this time is 13 - 15 °C, and in the south it rises to 17 - 18 °C. The spring warming of the water evens out the horizontal gradients, and the temperature difference between coastal areas And open sea does not exceed 0.5 °C. The heating of the surface layer, which begins in March, breaks the uniformity in the temperature distribution with depth. In June-September, there is a horizontal uniformity in the temperature distribution in surface layer. In August, which is the month of the greatest warming, the water temperature throughout the sea is 24 - 26 °C, and in the southern regions it rises to 28 °C. In August, the water temperature in shallow bays, for example, in Krasnovodsk, can reach 32 °C. The main feature of the water temperature field at this time is upwelling. It is observed annually along the entire eastern coast of the Middle Caspian and partially penetrates even into the South Caspian. The rise of cold deep waters occurs with varying intensity as a result of the influence of the prevailing summer season northwest winds. Wind this direction causes the outflow of warm surface waters from the coast and the rise of colder waters from the intermediate layers. Upwelling starts in June, but it reaches its highest intensity in July-August. As a result, a decrease in temperature is observed on the surface of the water (7 - 15 °C). Horizontal temperature gradients reach 2.3 °C at the surface and 4.2 °C at a depth of 20 m. in June to 43 - 45 ° N in September. Summer upwelling has great importance for the Caspian Sea, radically changing the dynamic processes in the deep water area. In the open areas of the sea in late May - early June, the formation of a temperature jump layer begins, which is most clearly expressed in August. Most often, it is located between the horizons of 20 and 30 m in the middle part of the sea and 30 and 40 m in the southern part. Vertical temperature gradients in the shock layer are very significant and can reach several degrees per meter. In the middle part of the sea, due to the surge near the eastern coast, the shock layer rises close to the surface. Since there is no stable baroclinic layer in the Caspian Sea with a large potential energy reserve similar to the main thermocline of the World Ocean, with the cessation of the effect of the prevailing winds that cause upwelling, and with the onset of autumn-winter convection in October-November, the temperature fields are rapidly reorganized to the winter regime. In the open sea, the water temperature in the surface layer drops in the middle part to 12 - 13 °C, in the southern part to 16 - 17 °C. In the vertical structure, the shock layer is washed out due to convective mixing and disappears by the end of November.

Compound

The salt composition of the waters of the closed Caspian Sea differs from that of the ocean. There are significant differences in the ratios of the concentrations of salt-forming ions, especially for the waters of areas under the direct influence of continental runoff. The process of metamorphization of sea waters under the influence of continental runoff leads to a decrease in the relative content of chlorides in the total amount of salts in sea waters, an increase in the relative amount of carbonates, sulfates, calcium, which are the main components in the chemical composition river waters. The most conservative ions are potassium, sodium, chloride and magnesium. The least conservative are calcium and bicarbonate ion. In the Caspian Sea, the content of calcium and magnesium cations is almost two times higher than in the Sea of ​​Azov, and sulfate anion is three times higher. The salinity of water changes especially sharply in the northern part of the sea: from 0.1 units. psu in the mouth areas of the Volga and the Urals up to 10 - 11 units. psu on the border with the Middle Caspian. Mineralization in shallow saline bays-kultuks can reach 60 - 100 g/kg. In the Northern Caspian, during the entire ice-free period from April to November, a quasi-latitudinal salinity front is observed. The greatest desalination associated with the spread of river runoff over the sea area is observed in June. On the formation of salinity field in the Northern Caspian big influence renders the wind field. In the middle and southern parts of the sea, salinity fluctuations are small. Basically, it is 11.2 - 12.8 units. psu, increasing in the south and east directions. Salinity increases insignificantly with depth (by 0.1 - 0.2 psu). In the deep-water part of the Caspian Sea, in the vertical salinity profile, characteristic troughs of isohalines and local extrema are observed in the area of ​​the eastern continental slope, which indicate the processes of near-bottom creep of waters becoming saline in the eastern shallow waters of the South Caspian. The salinity value also strongly depends on the sea level and (which is interrelated) on the amount of continental runoff.

General information

The relief of the northern part of the Caspian is a shallow wavy plain with banks and accumulative islands, the average depth of the Northern Caspian is about 4 - 8 meters, the maximum does not exceed 25 meters. The Mangyshlak threshold separates the Northern Caspian from the Middle. The Middle Caspian is quite deep, the depth of water in the Derbent depression reaches 788 meters. The Apsheron threshold separates the Middle and South Caspian. The South Caspian is considered deep water, the depth of water in the South Caspian depression reaches 1025 meters from the surface of the Caspian Sea. Shell sands are widespread on the Caspian shelf, deep-water areas are covered with silty sediments, and in some areas there is an outcrop of bedrock.

The climate of the Caspian Sea is continental in the northern part, temperate in the middle part and subtropical in the southern part. In winter average monthly temperature The Caspian varies from -8 -10 in the northern part to +8 - +10 in the southern part, in summer - from +24 - +25 in the northern part to +26 - +27 in the southern part. Maximum temperature fixed on the east coast - 44 degrees.

The average annual rainfall is 200 millimeters per year, ranging from 90-100 millimeters in the arid eastern part to 1,700 millimeters off the southwestern subtropical coast. Evaporation of water from the surface of the Caspian Sea is about 1000 millimeters per year, the most intense evaporation in the area of ​​the Absheron Peninsula and in the eastern part of the South Caspian is up to 1400 millimeters per year.

Winds often blow on the territory of the Caspian Sea, their average annual speed is 3-7 meters per second, the wind rose is dominated by northern winds. In the autumn and winter months, the winds increase, the wind speed often reaches 35-40 meters per second. The most windy territories are the Apsheron Peninsula and the environs of Makhachkala-Derbent, the most high wave- 11 meters.

The circulation of water in the Caspian Sea is connected with the runoff and winds. Because the most of The water flow falls on the Northern Caspian, the northern currents predominate. An intense northern current carries water from the Northern Caspian along the western coast to Absheron peninsula, where the flow splits into two branches, one of which moves further along West Bank, the other goes to the Eastern Caspian.

The fauna of the Caspian is represented by 1809 species, of which 415 are vertebrates. 101 species of fish are registered in the Caspian world, and most of the world's stocks of sturgeon are concentrated in it, as well as such freshwater fish as vobla, carp, pike perch. The Caspian Sea is the habitat of such fish as carp, mullet, sprat, kutum, bream, salmon, perch, pike. The Caspian Sea is also inhabited by a marine mammal - the Caspian seal. Since March 31, 2008, 363 dead seals have been found on the coast of the Caspian Sea in Kazakhstan.

The flora of the Caspian Sea and its coast is represented by 728 species. Of the plants in the Caspian Sea, algae predominate - blue-green, diatoms, red, brown, char and others, of flowering - zoster and ruppia. By origin, the flora belongs mainly to the Neogene age, however, some plants were brought into the Caspian Sea by man either consciously or on the bottoms of ships.

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On Sunday, August 12, in Kazakhstan's Aktau, the presidents of Azerbaijan, Iran, Kazakhstan, Russia and Turkmenistan signed the Convention on the Legal Status of the Caspian Sea. Previously, its status was regulated by the Soviet-Iranian treaties, in which the Caspian Sea was defined as a closed (inland) sea, and each Caspian state had sovereign rights to a 10-mile zone and equal rights to the rest of the sea.

Now, according to the new convention, each country has its own territorial waters (zones 15 miles wide). In addition, the provisions of the UN Convention on the Law of the Sea of ​​1982 will not apply to the Caspian Sea, the seabed will be delimited into sectors, as is done by neighbors on the seas, and sovereignty over the water column will be established on the basis of the principle that this is a lake.

Why is the Caspian considered neither a lake nor a sea?

To be considered a sea, the Caspian must have access to the ocean, this is one of the most important conditions for a body of water to be called a sea. But the Caspian has no access to the ocean, so it is considered a closed body of water, not connected to the oceans.

The second feature that distinguishes sea water from lake water is their high salinity. The water in the Caspian Sea is really salty, but in its own way salt composition it occupies an intermediate position between the river and the ocean. In addition, in the Caspian Sea, salinity increases towards the south. The Volga delta contains from 0.3‰ salts, and eastern regions In the South and Middle Caspian, salinity already reaches 13-14‰. And if we talk about the salinity of the World Ocean, then it averages 34.7 ‰.

Due to specific geographical and hydrological characteristics the reservoir received a special legal status. The summit participants decided that the Caspian Sea is an inland water body that has no direct connection with the World Ocean, and therefore cannot be considered a sea, and at the same time, due to its size, water composition and bottom features, it cannot be considered a lake.

What has been achieved since the signing of the Convention?

The new treaty expands the possibilities for cooperation between countries, and also involves limiting any military presence of third countries. According to political scientist, director of the Institute of Recent States Alexei Martynov, the main achievement of the last summit is that its participants managed to stop any talk about the possible construction of NATO military bases and infrastructure facilities in the Caspian Sea.

“The most important thing that has been achieved is to fix that the Caspian will be demilitarized for all the Caspian states. There will be no other military, except for those representing the countries that have signed the Caspian Agreement. This is a fundamental and main issue that was important to fix. Everything else, that is divided in proportion to the zone of influence, the zone of extraction of bioresources, the zone of extraction of shelf resources was not so important. As we remember, in the last twenty years, the military has been actively striving for the region. The USA even wanted to build their own military base", says Martynov.

In addition to the distribution of the shares of each country in the oil and gas fields of the Caspian basin, the Convention also provides for the construction of pipelines. As stated in the document, the rules for their laying provide for the consent of only neighboring countries, and not all countries of the Caspian Sea. After the signing of the agreement, Turkmenistan, in particular, stated that it was ready to lay pipelines along the bottom of the Caspian Sea, which would allow it to export its gas through Azerbaijan to Europe. The consent of Russia, which previously insisted that the project could only be implemented with the permission of all five Caspian states, is no longer required. The gas pipeline is planned to be connected in the future to the Trans-Anatolian gas pipeline, through which natural gas will go through the territory of Azerbaijan, Georgia and Turkey to Greece.

“Turkmenistan is not a foreign country to us, but our partner, a country that we consider very important for us in the post-Soviet space. We cannot be against them receiving an additional impetus for development through such pipeline projects. Gas has been coming from Turkmenistan and other countries through a different pipeline system for a long time, somewhere it even mixes with Russian gas, and there is nothing wrong with that. If this project works, then everyone will benefit, including Russia. In no case should the project be considered as a kind of competition. The European market is so big and insatiable, I mean the energy market, that there is enough space for everyone,” says Martynov.

Today, almost all Turkmen gas is supplied to China, where Russia also intends to supply natural gas. For this purpose, in particular, a large-scale project for the construction of the Power of Siberia gas pipeline is being implemented. Thus, the geography of gas supplies from both countries may expand - Turkmenistan will gain access to the European market, and Russia will be able to increase its gas supplies to China.

Location

Geographical position

• The Caspian Sea is located at the junction of two parts of the Eurasian continent - Europe and Asia. The Caspian Sea is similar in shape to the Latin letter S, the length of the Caspian Sea from north to south is approximately 1200 kilometers (36 ° 34 "- 47 ° 13" N), from west to east - from 195 to 435 kilometers, on average 310-320 kilometers (46° - 56° E).

The Caspian Sea is conditionally divided according to physical and geographical conditions into 3 parts - the Northern Caspian, the Middle Caspian and the Southern Caspian. The conditional border between the North and Middle Caspian is passed along the line Chechen (island) - Tyub-Karagansky cape, between the Middle and South Caspian - along the line Zhiloy (island) - Gan-Gulu (cape). The area of ​​the Northern, Middle and Southern Caspian is 25, 36, 39 percent respectively.

Caspian Sea- the largest lake on Earth, located at the junction of Europe and Asia lake Water level of the oceans

Caspian Sea- the largest lake on Earth, located at the junction of Europe and Asia, called the sea because of its size. The Caspian Sea is a drainless lake, and the water in it is salty, from 0.05‰ near the mouth of the Volga to from 11-13‰ in the southeast. The water level is subject to fluctuations, currently - about -28 m below sea level. The area of ​​the Caspian Sea is currently approximately 371,000 km², the maximum depth is 1025 m.

Coast of the Caspian Sea

Peninsulas of the Caspian Sea

• Large peninsulas of the Caspian Sea:

• Absheron Peninsula, located on the western coast of the Caspian Sea in Azerbaijan, at the northeastern end of the Greater Caucasus, the cities of Baku and Sumgayit are located on its territory

• Mangyshlak, located on the eastern coast of the Caspian Sea, on the territory of Kazakhstan, on its territory is the city of Aktau.

Islands of the Caspian Sea

• There are about 50 large and medium-sized islands in the Caspian Sea with a total area of ​​approximately 350 square kilometers.

• The largest islands:

Bays of the Caspian Sea

• Large bays of the Caspian Sea:

• Turkmenbashi (bay) (former Krasnovodsk),

• Hyrcanus (former Astarabad) and

• Anzali (former Pahlavi).

Rivers flowing into the Caspian Sea

• Delta of the Volga. View from space.

130 rivers flow into the Caspian Sea, of which 9 rivers have a mouth in the form of a delta. Large rivers flowing into the Caspian Sea - Volga, Terek (Russia), Ural, Emba (Kazakhstan), Kura (Azerbaijan), Samur (Russian border with Azerbaijan), Atrek (Turkmenistan) and others. The largest river flowing into the Caspian Sea is the Volga, its average annual drainage is 215-224 cubic kilometers. The Volga, Ural, Terek and Emba give up to 88 - 90 annual drainage of the Caspian Sea.

Caspian Sea Basin

Square basin The Caspian Sea is approximately 3.1 - 3.5 million square kilometers, which is approximately 10 percent of the world's closed water basins. The length of the Caspian Sea basin from north to south is about 2,500 kilometers, from west to east - about 1,000 kilometers. The Caspian Sea basin covers 9 states - Azerbaijan, Armenia, Georgia, Iran, Kazakhstan, Russia, Uzbekistan, Turkey and Turkmenistan.

coastal states

• The Caspian Sea washes the shores of five coastal states:

• Russia (Dagestan, Kalmykia and Astrakhan region) - in the west and north-west, the length of the coastline is 695 kilometers

• Kazakhstan - in the north, northeast and east, the length of the coastline is 2320 kilometers

• Turkmenistan - in the southeast, the length of the coastline is 1200 kilometers

• Iran - in the south, the length of the coastline - 724 kilometers

• Azerbaijan - in the southwest, the length of the coastline is 955 kilometers

Cities on the coast of the Caspian Sea

• Historical part of the city of Baku, view of the Caspian Sea

The largest port city on the Caspian Sea is Baku, the capital of Azerbaijan, which is located in the southern part of the Absheron Peninsula and has a population of 2,070 (2003). Other major Azerbaijani Caspian cities are Sumgayit, which is located in the northern part of the Absheron Peninsula, and Lenkoran, which is located near the southern border of Azerbaijan. To the South-East of the Absheron Peninsula, there is a settlement of oil workers Oil Rocks, whose facilities are on artificial islands, overpasses and technological sites.

• Large Russian cities - the capital of Dagestan Makhachkala and the southernmost city of Russia Derbent - are located on the western coast of the Caspian Sea. Astrakhan is also considered a port city of the Caspian Sea, which, however, is not located on the shores of the Caspian Sea, but in the Volga Delta, 60 kilometers from the northern coast of the Caspian Sea.

• On the eastern shore of the Caspian Sea is the Kazakh city - the port of Aktau, south of Kara-Bogaz-Gol on the northern shore of the Krasnovodsk Gulf - the Turkmen city of Turkmenbashi, formerly Krasnovodsk. Several Caspian cities are located on the southern (Iranian) coast, the largest of them is Anzali.

Physiography

• Area, depth, volume of water

The area and volume of water in the Caspian Sea varies significantly depending on fluctuations in water levels. At a water level of -26.75 m, the area was approximately 392,600 square kilometers, the volume of water was 78,648 cubic kilometers, which is approximately 44 percent of the world's lake water reserves. The maximum depth of the Caspian Sea is in the South Caspian depression, 1025 meters from its surface level. In terms of maximum depth, the Caspian Sea is second only to Baikal (1620 m) and Tanganyika (1435 m). The average depth of the Caspian Sea, calculated from the bathygraphic curve, is 208 meters. At the same time, the northern part of the Caspian Sea is shallow, its maximum depth does not exceed 25 meters, and the average depth is 4 meters.

Water level fluctuations

The water level in the Caspian Sea is subject to significant fluctuations. According to modern science, over the past 3 thousand years, the amplitude of changes in the water level of the Caspian Sea has amounted to 15 meters. Instrumental measurement of the level of the Caspian Sea and systematic observations of its fluctuations have been carried out since the year, during this time the highest water level was recorded in 1882 (-25.2 m.), the lowest - in the year (-29.0 m.), from In 1978, the water level went down and in the year it reached 26.6 m, since 1996 there has been an upward trend again. Scientists associate the causes of changes in the water level of the Caspian Sea with climatic, geological and anthropological factors.

Water temperature

• The average monthly water temperature of the Caspian Sea ranges from 0 degrees in the northern part to +10 in the southern part, and approximately +23 - +26 throughout the Caspian Sea in the summer months. At great depths, the water temperature is approximately +6 - +7 and practically does not undergo seasonal changes.

In winter, part of the surface of the Caspian Sea freezes. In the northern part of the Caspian Sea, the surface is covered with a layer of ice up to 2 meters thick, freezing begins in mid-November, and ice melts in late February. The freezing boundary runs approximately along the line Chechen Island - Mangyshlak, on the Apsheron Peninsula, the formation and drift of ice is observed approximately once every 10-11 years.

Water composition

• Water composition

• The salinity of the water of the Caspian Sea varies from 0.3 ppm in the northern part near the Volga delta to 13.5 ppm near the southeastern shores, in most of the Caspian Sea it is 12.6 - 13.2 ppm. In winter, due to the freezing of the Volga, the salinity of the water in the northern part of the Caspian Sea increases.

• Bottom relief

The relief of the northern part of the Caspian is a shallow wavy plain with banks and accumulative islands, the average depth of the Northern Caspian is about 4 - 8 meters, the maximum does not exceed 25 meters. The Mangyshlak threshold separates the Northern Caspian from the Middle. The Middle Caspian is quite deep, the depth of water in the Derbent depression reaches 788 meters. The Apsheron threshold separates the Middle and South Caspian. The South Caspian is considered deep water, the depth of water in the South Caspian depression reaches 1025 meters from the surface of the Caspian Sea. Shell sands are widespread on the Caspian shelf, deep-water areas are covered with silty sediments, and in some areas there is an outcrop of bedrock.

Climate

The climate of the Caspian Sea is continental in the northern part, temperate in the middle part and subtropical in the southern part. In winter, the average monthly temperature of the Caspian varies from -8 -10 in the northern part to +8 - +10 in the southern part, in summer - from +24 - +25 in the northern part to +26 - +27 in the southern part. The maximum temperature recorded on the east coast is 44 degrees.

The average annual rainfall is 200 millimeters per year, ranging from 90-100 millimeters in the arid eastern part to 1,700 millimeters off the southwestern subtropical coast. Evaporation of water from the surface of the Caspian Sea is about 1000 millimeters per year, the most intense evaporation in the area of ​​the Absheron Peninsula and in the eastern part of the South Caspian is up to 1400 millimeters per year.

Winds often blow on the territory of the Caspian Sea, their average annual speed is 3-7 meters per second, north winds prevail in the wind rose. In the autumn and winter months, the winds increase, the wind speed often reaches 35-40 meters per second. The most windy territories are the Apsheron Peninsula and the environs of Makhachkala - Derbent, where the highest wave was recorded - 11 meters.

currents

The circulation of water in the Caspian Sea is connected with the runoff and winds. Since most of the water flow falls on the Northern Caspian, northern currents predominate. An intense northern current carries water from the Northern Caspian along the western coast to the Absheron Peninsula, where the current is divided into two branches, one of which moves further along the western coast, the other goes to the Eastern Caspian.

Animal and plant world

• ,

  • Mining of oil and gas

  • Many oil and gas fields are being developed in the Caspian Sea. The proven oil resources in the Caspian Sea are about 10 billion tons, the total resources of oil and gas condensate are estimated at 18-20 billion tons.

  • Oil production in the Caspian Sea began in 1820, when the first oil well was drilled on the Absheron shelf. In the second half of the 19th century, oil production began on an industrial scale on the Absheron Peninsula, and then on other territories.

  • In addition to oil and gas production, salt, limestone, stone, sand, and clay are also mined on the coast of the Caspian Sea and the Caspian shelf.

  • Shipping

  • Shipping is developed in the Caspian Sea. Ferry crossings operate on the Caspian Sea, in particular, Baku - Turkmenbashi, Baku - Aktau, Makhachkala - Aktau. The Caspian Sea has a navigable connection with the Sea of ​​Azov through the Volga and Don rivers and the Volga-Don Canal.

  
  

  Fishing and seafood

  • Fishing (sturgeon, bream, carp, pike perch, sprat), caviar production, as well as seal fishing. More than 90 percent of the world's sturgeon catch is carried out in the Caspian Sea. In addition to industrial production, illegal production of sturgeon and their caviar flourishes in the Caspian Sea.

  • Recreational resources

  natural environment Caspian coast with sandy beaches, mineral waters and therapeutic mud in the coastal zone creates good conditions for rest and treatment. At the same time, in terms of the degree of development of resorts and the tourism industry, the Caspian coast is noticeably losing Black Sea coast Caucasus. However, in last years the tourism industry is actively developing on the coast of Azerbaijan, Iran, Turkmenistan and Russian Dagestan.

  
  

  Ecological problems

  The environmental problems of the Caspian Sea are associated with water pollution as a result of oil production and transportation on the continental shelf, the flow of pollutants from the Volga and other rivers flowing into the Caspian Sea, the vital activity of coastal cities, as well as the flooding of individual objects due to the rise in the level of the Caspian Sea. Predatory harvesting of sturgeons and their caviar, rampant poaching lead to a decrease in the number of sturgeons and forced restrictions on their production and export.

  
  

  International status of the Caspian Sea

  • Border dispute over the status of the Caspian Sea

  After the collapse of the USSR, the division of the Caspian Sea has long been and still remains the subject of unsettled disagreements related to the division of the resources of the Caspian shelf - oil and gas, as well as biological resources. For a long time there were negotiations between littoral states about the status of the Caspian Sea - Azerbaijan, Kazakhstan and Turkmenistan insisted on dividing the Caspian along the median line, Iran - on dividing the Caspian along one fifth between all the Caspian states. In 2003, Russia, Azerbaijan and Kazakhstan signed an agreement on the partial division of the Caspian Sea along the median line