Caspian Sea where it is located. Caspian Sea Map

Is it correct to call the Caspian Sea?

It is known that the sea is part of the World Ocean. From this geographically correct point of view, the Caspian Sea cannot be considered a sea, for it is separated from the ocean by huge tracts of land. The shortest distance from the Caspian to the Black Sea, the closest of the seas included in the World Ocean system, is 500 kilometers. Therefore, it would be more correct to speak of the Caspian as a lake. This largest lake in the world is often referred to simply as the Caspian or the sea-lake.

The Caspian Sea has a number of signs of the sea: its water is salty (however, there are other salt lakes), the area is not much inferior to the area of ​​such seas as the Black, Baltic, Red, North and even exceeds the area of ​​the Azov and some others (however, the Canadian Lake Superior also has a huge area , like the three seas of Azov). Fierce storm winds are frequent in the Caspian, huge waves(and this is not uncommon on Lake Baikal).

So the Caspian Sea is a lake after all? That's on Wikipedia it is written And the Great Soviet Encyclopedia answers that no one has yet been able to give an exact definition of this issue - "There is no generally accepted classification."

Do you know why this is very important and fundamental? And here's why ...

The lake belongs to inland waters - sovereign territories of coastal states, to which the international regime does not apply (the principle of UN non-interference in the internal affairs of states). But the sea area is divided in a different way, and the rights of coastal states are completely different here.

In terms of its geographical position, the Caspian itself, in contrast to the surrounding land territories, for many centuries has not been the object of any targeted attention from the coastal states. Only at the beginning of the 19th century. The first treaties were concluded between Russia and Persia: Gulistan (1813) 4 and Turkmanchay (1828), summing up the results of the Russo-Persian war, as a result of which Russia annexed a number of Transcaucasian territories and received the exclusive right to maintain a military fleet in the Caspian sea. Russian and Persian merchants were allowed to trade freely on the territory of both states and use the Caspian for the transport of goods. The Turkmanchay agreement confirmed all these provisions and became the basis for the maintenance of international relations between the parties until 1917.

After the October Revolution of 1917, in a note from the new government of Russia that came to power on January 14, 1918, it renounced its exclusive military presence in the Caspian Sea. The treaty between the RSFSR and Persia of February 26, 1921 declared invalid all agreements concluded before it by the tsarist government. The Caspian Sea became a reservoir of common use of the parties: both states were granted equal rights of free navigation, except for cases when the crews of Iranian ships could include citizens of third countries using the service for unfriendly purposes (Article 7). 1921 Treaty maritime border between the parties did not provide.

In August 1935, the following treaty was signed, the parties to which were new subjects of international law - the Soviet Union and Iran, which came under the new name. The parties confirmed the provisions of the 1921 treaty, but introduced into the agreement a new concept for the Caspian - a 10-mile fishing zone, which limited the spatial limits of this fishery for its participants. This was done in order to control and preserve the living resources of the reservoir.

In the context of the outbreak of World War II, unleashed by Germany, an urgent need arose to conclude a new agreement on trade and navigation in the Caspian Sea between the USSR and Iran. The reason for this was the concern of the Soviet side, caused by Germany's interest in intensifying its trade relations with Iran and the danger of using the Caspian Sea as one of the stages of the transit route. The treaty between the USSR and Iran, signed in 1940, 10 protected the Caspian Sea from such a prospect: it repeated the main provisions of the previous agreements, which provided for the stay in its waters of the ships of only these two Caspian states. It also included a norm about its indefinite validity.

The collapse of the Soviet Union radically changed the regional situation in the former Soviet space, in particular in the Caspian region. Among the large number of new problems, the problem of the Caspian Sea has arisen. Instead of two states - the USSR and Iran, which previously bilaterally resolved all emerging issues of maritime navigation, fishing and the use of other living and nonliving resources, now there are five of them. Of the former, only Iran remained, the place of the USSR as succession was taken by Russia, the other three are new states: Azerbaijan, Kazakhstan, Turkmenistan. They had access to the Caspian before, but only as republics of the USSR, and not as independent states. Now, having become independent and sovereign, they have the opportunity to participate on an equal footing with Russia and Iran in the discussion and decision-making in considering all the above issues. This was reflected in the attitude of these states towards the Caspian, since all five states that had access to it showed the same interest in the use of its living and nonliving resources. And this is logical, and most importantly, justified: the Caspian Sea is rich in natural resources, both fish stocks and black gold - oil and blue fuel - gas. Exploration and production of the last two resources have long been the subject of the most heated and protracted negotiations. But they are not the only ones.

Besides having rich mineral resources About 120 species and subspecies of fish live in the waters of the Caspian Sea; the world gene pool of sturgeons is located here, the catch of which until recently amounted to 90% of their total world catch.

Due to its location, the Caspian has traditionally and for a long time been widely used for shipping, acting as a kind of transport artery between the peoples of the coastal states. There are such large seaports like the Russian Astrakhan, the capital of Azerbaijan Baku, the Turkmen Turkmenbashy, the Iranian Anzeli and the Kazakhstani Aktau, between which routes for the movement of trade, cargo and passenger sea transport have long been laid.

And yet, the main object of attention of the Caspian states is its mineral resources - oil and natural gas, which each of them can claim within the boundaries that must be determined by them collectively on the basis of international law. And to do this, they will have to divide among themselves the Caspian Sea and its bottom, in the depths of which its oil and gas are hidden, and develop rules for their extraction with minimal damage to a very fragile environment, primarily the marine environment and its living inhabitants.

The main obstacle in resolving the issue of the start of extensive production of the Caspian mineral resources for the Caspian states continues to be its international legal status: should it be considered a sea or a lake? The complexity of the issue lies in the fact that these states themselves must solve it, and there is no agreement in their ranks so far. But at the same time, each of them seeks to start the production of Caspian oil and natural gas as soon as possible and make their sale abroad a permanent source of funds for the formation of their budget.

Therefore, the oil companies of Azerbaijan, Kazakhstan and Turkmenistan, without waiting for the end of the settlement of the existing differences on the territorial division of the Caspian, have already begun active production of its oil, hoping to stop being dependent on Russia, turn their countries into oil producing countries and, in this capacity, begin to build their own long-term trading relations with neighbors.

However, the question of the status of the Caspian Sea remains unresolved. Regardless of whether the Caspian states agree to consider it a "sea" or a "lake", they will have to apply the principles corresponding to the choice made to the territorial division of its water area and the bottom, or develop their own in this case.

Kazakhstan was in favor of recognizing the Caspian by the sea. Such recognition will make it possible to apply to the division of the Caspian the provisions of the 1982 UN Convention on the Law of the Sea on internal waters, territorial sea, exclusive economic zone, continental shelf. This would allow the coastal states to acquire sovereignty over the subsoil of the territorial sea (Art. 2) and exclusive rights to exploration and development of the resources of the continental shelf (Art. 77). But the Caspian cannot be called a sea from the standpoint of the 1982 UN Convention on the Law of the Sea, since this body of water is closed and has no natural connection with the world's oceans.

In this case, the option of joint use of its water area and bottom resources is also excluded.

In the treaties between the USSR and Iran, the Caspian Sea was considered as a border lake. With the granting of the legal status of the "lake" to the Caspian Sea, it is supposed to be divided into sectors, as is done in relation to border lakes. But in international law there is no rule obliging states to do just that: division into sectors is an established practice.

The Russian Foreign Ministry has repeatedly made statements that the Caspian is a lake, and its waters and subsoil are the common property of coastal states. Iran also considers the Caspian Sea as a lake from the position enshrined in treaties with the USSR. The government of the country believes that this status implies the creation of a consortium for the unified management of production and the use of its resources. Caspian states... This opinion is also expressed by some authors, for example, R. Mamedov believes that with this status, the extraction of hydrocarbon resources in the Caspian by these states should be carried out jointly.

In the literature, there has been a proposal to give the Caspian Sea the status of a lake "sui generis", and in this case we are talking about a special international legal status such a lake and its special regime. Under the regime, states are supposed to jointly develop their own rules for the use of its resources.

Thus, the recognition of the Caspian by a lake does not require its obligatory division into sectors - each coastal state has its own part. In addition, in international law, there are no norms at all on the division of lakes between states: this is their good will, behind which certain internal interests may be hidden.

At present, all the Caspian states recognize that the modern legal regime was established by the established practice of its use, but now the Caspian is in actual common use of not two, but five states. Back at the meeting of foreign ministers held in Ashgabat on November 12, 1996, the Caspian states confirmed that the status of the Caspian Sea can be changed only with the consent of all five coastal states. Later, this was also confirmed by Russia and Azerbaijan in a joint statement of January 9, 2001 on the principles of cooperation, as well as in the Declaration on Cooperation in the Caspian Sea signed between Kazakhstan and Russia of October 9, 2000.

But in the course of numerous Caspian negotiations, conferences and four summits of the Caspian states (Ashgabat summit on April 23-24, 2002, Tehran summit on October 16, 2007, Baku summit on November 18, 2010 and Astrakhan summit on September 29, 2014) it was never achieved.

Cooperation at the bilateral and trilateral levels is still more productive. Back in May 2003, Russia, Azerbaijan and Kazakhstan signed an agreement on the junction point of the delimitation lines of adjacent sections of the Caspian Sea bottom, which was based on previous bilateral agreements. In the current situation, by its participation in these agreements, Russia, as it were, confirmed that the agreements between the USSR and Iran are outdated and do not correspond to the existing realities.

In the Agreement of July 6, 1998 between the Russian Federation and the Republic of Kazakhstan on the delimitation of the bottom of the northern part of the Caspian Sea in order to exercise sovereign rights to subsoil use, it was announced that the seafloor was delimited between adjacent and opposing sides along a modified median line based on the principle of justice and the agreement of the parties. The states have sovereign rights to the bottom of the plot, but at the same time their common use of the water surface is preserved.

Iran perceived this agreement as a separate one and in violation of the previous Treaties with the USSR in 1921 and 1940. However, it should be noted that in the preamble to the 1998 agreement, to which Russia and Kazakhstan were parties, the agreement was viewed as a temporary measure pending the signing of the convention by all the Caspian states.

Later, on July 19 of the same year, Iran and Russia made a joint statement in which they proposed three possible scenarios for the delimitation of the Caspian. First, the sea should be shared on the basis of the condominium principle. The second scenario boils down to dividing the water area, waters, bottom and subsoil into national sectors. The third scenario, which is a compromise between the first and second options, assumes that only the seabed is divided between the coastal states, and the water surface is considered common and open to all coastal countries.

The existing options for the delimitation of the Caspian, including those mentioned above, are possible only if there is a good political will of the parties. Azerbaijan and Kazakhstan have clearly expressed their position from the very beginning of the multilateral consultation process. Azerbaijan considers the Caspian Sea to be a lake and, therefore, it should be divided. Kazakhstan proposes to consider the Caspian an enclosed sea, referring to the 1982 UN Convention (Articles 122, 123), and, accordingly, advocates its division in the spirit of the Convention. Turkmenistan has long supported the idea of ​​joint management and use of the Caspian, but foreign companies already developing resources off the coast of Turkmenistan influenced the policy of its president, who began to object to the establishment of a condominium regime, supporting the position of dividing the sea.

Azerbaijan was the first of the Caspian states to start using the hydrocarbon resources of the Caspian under the new conditions. After the conclusion of the "Deal of the Century" in September 1994, Baku expressed a desire to declare the adjacent sector an integral part of its territory. This provision was also enshrined in the Constitution of Azerbaijan, adopted in order to exercise sovereign rights to subsoil use, Moscow, July 6, 1998 at a referendum on November 12, 1995 (Article 11). But such a radical position from the very beginning did not correspond to the interests of all other coastal states, especially Russia, which expresses fears that this will open access to the Caspian Sea to countries in other regions. Azerbaijan agreed to a compromise. In the Agreement between the Russian Federation and Azerbaijan on the delimitation of adjacent areas of the Caspian Sea in 2002, a provision was fixed in which the seabed was divided using the median line, and the water area of ​​the reservoir remained in joint use.

Unlike Azerbaijan, which expressed a desire to completely divide the Caspian, Iran offers to leave its subsoil and water in joint use, but does not object to the option of dividing the Caspian into 5 equal parts. Accordingly, each member of the Caspian Five would be allocated 20 percent of the total area of ​​the reservoir.

Russia's point of view was changing. For a long time Moscow insisted on the establishment of a condominium, but wishing to build a long-term policy with its neighbors, who did not find it profitable to consider the Caspian as the property of the five coastal states, changed its position. This then pushed the states to start a new stage of negotiations, upon completion of which in 1998 the above Agreement was signed, where Russia declared that it was “ripe” for the division of the Caspian. Its main principle was the position “common water - we divide the bottom”.

Taking into account the fact that some of the Caspian states, namely Azerbaijan, Kazakhstan and Russia, have reached agreements on the conditional delimitation of spaces in the Caspian, we can conclude that they are actually satisfied with the already established regime with the division of its bottom along the modified median line and the joint use of the surface reservoir for shipping and fishing.

However, the lack of complete clarity and unity in the position of all coastal countries prevents the Caspian states themselves from developing oil production. And oil is of key importance to them. There are no unambiguous data regarding their reserves in the Caspian Sea. According to the US Energy Information Agency in 2003, the Caspian was ranked second in oil reserves and third in gas reserves. The data of the Russian side are different: they speak of artificial overstatement by Western experts of the energy resources of the Caspian Sea. The discrepancies in assessments are due to the political and economic interests of regional and external players. The factor of data distortion was the geopolitical significance of the region, with which the foreign policy plans of the United States and the EU are connected. Back in 1997, Zbigniew Brzezinski expressed the opinion that this region is the “Eurasian Balkans”.

Caspandyskoe mOre(Caspian Sea) is the largest enclosed body of water on Earth. In size, the Caspian Sea is much larger than such lakes as the Upper, Victoria, Huron, Michigan, Baikal. Formally, the Caspian Sea is a closed lake. However, given its large size, brackish waters and a regime similar to the sea, this body of water is called the sea.

According to one hypothesis, the Caspian Sea (among the ancient Slavs - the Khvalynskoe Sea) got its name in honor of the Caspian tribes who lived on its southwestern coast before our era.

The Caspian Sea washes the shores of five states: Russia, Azerbaijan, Iran, Turkmenistan and Kazakhstan.

The Caspian Sea is elongated in the meridional direction and is located between 36 ° 33΄ and 47 ° 07΄ N. and 45 ° 43΄ and 54 ° 03΄ E (excluding the Kara-Bogaz-Gol bay). The length of the sea along the meridian is about 1200 km; the average width is 310 km. The northern coast of the Caspian Sea is bordered by the Caspian lowland, the eastern coast by the deserts of Central Asia; in the west, the mountains of the Caucasus approach the sea, in the south, near the coast, the Elburs ridge stretches.

The surface of the Caspian Sea is significantly below the level of the World Ocean. Its current level fluctuates around -27 ... -28 m. These levels correspond to the sea surface area of ​​390 and 380 thousand km 2 (excluding the Kara-Bogaz-Gol bay), the volume of waters 74.15 and 73.75 thousand km 3, average depth is about 190 m.

The Caspian Sea is traditionally divided into three large parts: the North (24% of the sea area), the Middle (36%) and the South Caspian (40%), significantly different in morphology and regime, as well as the large and isolated Kara-Bogaz-Gol bay. The northern shelf part of the sea is shallow: its average depth is 5–6 m, maximum depths are 15–25 m, and the volume is less than 1% of the total water mass of the sea. The Middle Caspian is a separate basin with an area of ​​maximum depths in the Derbent depression (788 m); its average depth is about 190 m. In the South Caspian the average and maximum depths are 345 and 1025 m (in the South Caspian depression); 65% of the water mass of the sea is concentrated here.

There are about 50 islands in the Caspian Sea with total area approximately 400 km 2; the main ones are Tyuleniy, Chechnya, Zyudev, Konevsky, Dzhambaysky, Durneva, Ogurchinsky, Apsheronsky. The length of the coastline is about 6.8 thousand km, with islands - up to 7.5 thousand km. The shores of the Caspian Sea are diverse. In the northern and eastern parts, they are rather heavily indented. There are large bays Kizlyarsky, Komsomolets, Mangyshlaksky, Kazakhsky, Kara-Bogaz-Gol, Krasnovodsky and Turkmensky, many bays; at west coast- Kyzylagachsky. The largest peninsulas are Agrakhanskiy, Buzachi, Tyub-Karagan, Mangyshlak, Krasnovodskiy, Cheleken and Apsheronskiy. The most common banks are accumulative; areas with abrasive shores are found along the contour of the Middle and South Caspian.

More than 130 rivers flow into the Caspian Sea, of which the largest is the Volga , Ural, Terek, Sulak, Samur, Kura, Sefidrud, Atrek, Emba (its runoff enters the sea only in high-water years). Nine rivers have deltas; the largest are located at the mouths of the Volga and Terek.

The main feature of the Caspian, as an endless reservoir, is instability and a wide range of long-term fluctuations in its level. This most important hydrological feature of the Caspian Sea has a significant impact on all its other hydrological characteristics, as well as on the structure and regime of river mouths and coastal zones. The level of the Caspian Sea varied in the range of ~ 200 m: from -140 to +50 m BS; in from -34 to -20 m BS. From the first third of the XIX century. and until 1977 the sea level dropped by about 3.8 m - to the lowest point in the last 400 years (-29.01 m BS). In 1978-1995 the level of the Caspian Sea rose by 2.35 m and reached -26.66 m BS. Since 1995, a certain downward trend in the level has dominated - to -27.69 m BS in 2013.

During large periods, the northern coast of the Caspian shifted to the Samarskaya Luka on the Volga, and perhaps even further. At maximum transgressions, the Caspian turned into waste lake: excess water drained through the Kuma-Manych depression into the Sea of ​​Azov and further into the Black Sea. In extreme regressions, the southern coast of the Caspian Sea shifted to the Apsheron sill.

Long-term fluctuations in the level of the Caspian Sea are explained by changes in the structure of the water balance of the Caspian Sea. The sea level rises when the input part of the water balance (primarily the river runoff) increases and exceeds the discharge part, and decreases if the river water inflow decreases. The total runoff of all rivers is on average 300 km 3 / year; at the same time, the five largest rivers account for almost 95% (the Volga gives 83%). During the period of the lowest sea level, in 1942-1977, the river flow was 275.3 km 3 / year (of which 234.6 km 3 / year - the Volga flow), precipitation - 70.9, groundwater flow - 4 km 3 / year, and evaporation and outflow into the Kara-Bogaz-Gol Bay - 354.79 and 9.8 km 3 / year. During the period of intensive sea level rise, in 1978–1995, - respectively 315 (Volga - 274.1), 86.1, 4, 348.79 and 8.7 km 3 / year; in the modern period - 287.4 (Volga - 248.2), 75.3, 4, 378.3 and 16.3 km 3 / year.

The intra-annual changes in the level of the Caspian Sea are characterized by a maximum in June – July and a minimum in February; the range of intra-annual level fluctuations is 30–40 cm. Surge-surging level fluctuations are manifested throughout the sea, but they are most significant in the northern part, where, with maximum surges, the level can rise by 2–4.5 m and “retreat” by several dozen kilometers inland, and during surges - to drop by 1–2.5 m. Seiche and tidal level fluctuations do not exceed 0.1–0.2 m.

Despite the relatively small size of the reservoir in the Caspian Sea, there is strong waves. The highest wave heights in the South Caspian can reach 10–11 m. Wave heights decrease in the direction from south to north. Storm excitement can develop at any time of the year, but more often and more dangerous in the cold half of the year.

The Caspian Sea as a whole is dominated by wind currents; nevertheless, runoff currents play a significant role in the estuarine seaside areas of large rivers. In the Middle Caspian, cyclonic water circulation prevails, in the South Caspian - anticyclonic. In the northern part of the sea, the patterns of wind currents are more irregular and depend on the characteristics and variability of the wind, the bottom topography and outlines of the banks, river runoff and aquatic vegetation.

Water temperature is subject to significant latitudinal and seasonal variations. In winter, it varies from 0–0.5 o C at the ice edge in the north of the sea to 10–11 o C in the south. In summer, the sea water temperature averages 23-28 o C, and in shallow coastal waters in the North Caspian it can reach 35-40 o C. At depths, a constant temperature is maintained: deeper than 100 m, it is 4-7 o C.

Only freezes in winter Northern part The Caspian Sea; in a harsh winter - the entire Northern Caspian and the coastal zones of the Middle Caspian. Freezing up in the Northern Caspian lasts from November to March.

The salinity of the water changes especially sharply in the northern part of the sea: from 0.1 ‰ on the estuarine coastal areas of the Volga and the Urals to 10–12 ‰ on the border with the Middle Caspian. In the North Caspian, the temporal variability of water salinity is also great. In the middle and southern parts of the sea, salinity fluctuations are small: mainly it is 12.5–13.5 ‰, increasing from north to south and from west to east. The highest water salinity is in the Kara-Bogaz-Gol Bay (up to 300 ‰). With depth, the salinity of water increases insignificantly (by 0.1–0.3 ‰). The average salinity of the sea is about 12.5 ‰.

More than a hundred species of fish live in the Caspian Sea and the mouths of the rivers flowing into it. There are Mediterranean and Arctic invaders. The object of the fishery is goby, herring, salmon, carp, mullet and sturgeon fish. The latter include five species: sturgeon, beluga, stellate sturgeon, thorn and sterlet. The sea is capable of producing annually up to 500-550 thousand tons of fish, if it is not allowed to be overfished. Of the marine mammals, the endemic Caspian seal lives in the Caspian Sea. 5-6 million waterfowl migrate through the Caspian region annually.

The economy of the Caspian Sea is associated with oil and gas production, shipping, fishing, seafood production, various salts and minerals (Kara-Bogaz-Gol Bay), using recreational resources... The explored oil resources in the Caspian Sea amount to about 10 billion tons, the total oil and gas condensate resources are estimated at 18–20 billion tons. Oil and gas production is being carried out on an ever-increasing scale. It is used by the Caspian Sea and by water transport, including along the river-sea and sea-river routes. The main ports of the Caspian are Astrakhan, Olya, Makhachkala (Russia), Aktau, Atyrau (Kazakhstan), Baku (Azerbaijan), Noushehr, Bender-Anzeli, Bender-Torkemen (Iran) and Turkmenbashi (Turkmenistan).

Economic activity and hydrological features of the Caspian Sea create a number of serious environmental and water management problems. Among them: anthropogenic pollution of river and sea ​​waters(mainly with oil products, phenols and synthetic surfactants), poaching and reduction of fish stock, especially sturgeon; damage to the population and coastal-coastal economic activities due to large-scale and rapid changes in the level of the reservoir, the impact of numerous hazardous hydrological phenomena and hydrological and morphological processes.

The total economic damage to all the Caspian countries associated with the rapid and significant recent rise in the level of the Caspian Sea, the flooding of part of the coastal land, the destruction of coasts and coastal structures, amounted to rough estimates from 15 to 30 billion US dollars. It took urgent engineering measures to protect the coast.

A sharp drop in the level of the Caspian Sea in the 1930-1970s. led to less damage, but they were significant. The navigable approach channels became shallow, the shallow seaside in the estuaries of the Volga and the Urals became heavily overgrown, which became an obstacle to the passage of fish into rivers for spawning. It was necessary to build fish-passage channels through the mentioned seaside.

Among the unsolved problems is the absence of an international agreement on the international legal status of the Caspian Sea, the division of its water area, bottom and subsoil.

The Caspian Sea is the object of many years of research by specialists from all the Caspian states. Such domestic organizations as the State Oceanographic Institute, the Institute of Oceanology of the Russian Academy of Sciences, the Hydrometeorological Center of Russia, the Caspian Research Institute of Fisheries, the Faculty of Geography of the Moscow state university and etc.

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42 ° N sh. 51 ° East etc. HGI AMOL

Caspian Sea- the largest closed body of water on Earth, which can be classified as the largest closed lake, or as a full-fledged sea, due to its size, as well as due to the fact that its bed is composed of an oceanic type of crust. Located at the junction of Europe and Asia. The water in the Caspian is brackish, - from 0.05 ‰ near the mouth of the Volga to 11-13 ‰ in the southeast. The water level is subject to fluctuations, according to 2009 data was 27.16 m below sea level. The area of ​​the Caspian Sea is currently about 371,000 km², the maximum depth is 1025 m.

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Subtitles

Etymology

Geographical position

The Caspian Sea is located at the junction of Europe and Asia. The length of the sea from north to south is about 1200 kilometers (36 ° 34 "-47 ° 13" N), from west to east - from 195 to 435 kilometers, on average 310-320 kilometers (46 ° -56 ° E etc.).

According to physical and geographical conditions, the Caspian Sea is conditionally divided into three parts - the North Caspian (25% of the sea area), the Middle Caspian (36%) and the South Caspian (39%). The conditional border between the North and Middle Caspian runs along the line of Chechen Island - Cape Tyub-Karagan, between the Middle and South Caspian - along the line of Chilov Island - Cape Gan-Gulu.

Coast

The territory adjacent to the Caspian Sea is called the Caspian region.

Peninsula

• Absheron Peninsula, located on the western coast of the Caspian Sea on the territory of Azerbaijan, at the northeastern end of the Greater Caucasus, on its territory are the cities of Baku and Sumgait
• Mangyshlak, located on east coast Of the Caspian Sea, on the territory of Kazakhstan, on its territory there is the city of Aktau

Islands

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

The largest islands:

Gulfs

Large bays:

Kara-Bogaz-Gol

The east coast is salt Lake Kara-Bogaz-Gol, which until 1980 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 several meters. In 1992, the strait was restored, along it the water leaves the Caspian Sea to Kara-Bogaz-Gol and evaporates there. Every year from the Caspian Sea, Kara-Bogaz-Gol receives 8-10 cubic kilometers of water (according to other sources - 25 cubic kilometers) and about 15 million tons of salt.

Rivers flowing into the Caspian Sea

130 rivers flow into the Caspian Sea, 9 of which have delta-shaped estuaries. Large rivers flowing into the Caspian Sea are Volga, Terek, Sulak, Samur (Russia), Ural, Emba (Kazakhstan), Kura (Azerbaijan), Atrek (Turkmenistan), Sefidrud (Iran). Largest river The Volga, which flows into the Caspian Sea, has an average annual runoff of 215-224 cubic kilometers. The Volga, Ural, Terek, Sulak and Emba provide up to 88-90% of the annual runoff into the Caspian Sea.

Basin of the Caspian Sea

Coastal states

According to the Intergovernmental Economic Conference of the Caspian States:

The Caspian Sea washes the shores of five coastal states:

Cities on the coast of the Caspian Sea

On the Russian coast cities are located - Lagan, Makhachkala, Kaspiysk, Izberbash, Dagestan Lights and the most Southern City Russia Derbent. Astrakhan is also considered the 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 north coast The Caspian Sea.

Physiography

Area, depth, volume of water

The area and volume of water in the Caspian Sea varies significantly depending on the fluctuations in the water level. At a water level of -26.75 m, the area is approximately 371,000 square kilometers, the volume of water is 78,648 cubic kilometers, which is approximately 44% of the world's lake water reserves. The maximum depth of the Caspian Sea is in the South Caspian depression, 1025 meters above its surface. 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 according to the bathygraphic curve, is 208 meters. At the same time, the northern part of the Caspian is shallow, its maximum depth does not exceed 25 meters, and the average depth is 4 meters.

Water level fluctuations

Vegetable world

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, charovy and others, from flowering plants - zostera and ruppia. In origin, the flora belongs mainly to the Neogene age, however, some plants were introduced into the Caspian Sea by humans deliberately, or on the bottoms of ships.

Story

Origin

The Caspian Sea is of oceanic origin - its bed is composed of oceanic crust. 13 million liters. n. the formed Alps separated the Sarmatian Sea from the Mediterranean. 3.4 - 1.8 million liters. n. (Pliocene) the Akchagyl Sea existed, the deposits of which were investigated by N.I. Andrusov. Originally formed on the site of the dried-up Pontic Sea, from which Lake Balakhany remained (on the territory of the southern Caspian Sea). The Akchagyl transgression was replaced by the Domashka regression (a drop of 20 - 40 m from the level of the Akchagyl basin), accompanied by strong desalination of sea waters, which is due to the termination of the supply of sea (oceanic) waters from the outside. After a short Domashkin regression at the beginning of the Quaternary period (Eopleistocene), the Caspian is almost restored in the form of the Absheron Sea, which covers the Caspian and floods the territories of Turkmenistan and the Lower Volga region. At the beginning of the Absheron transgression, the basin turns into a brackish water body. The Absheron Sea exists from 1.7 to 1 million years ago. The beginning of the Pleistocene in the Caspian Sea was marked by a long and deep Türkyan regression (-150 m to -200 m), corresponding to the Matuyama-Brunhes magnetic inversion (0.8 million years ago). The water mass of the Türkyan basin with an area of ​​208 thousand km² was concentrated in the South Caspian and part of the Middle Caspian basins, between which there was a shallow strait in the area of ​​the Apsheron threshold. In the Early Neopleistocene, after the Türkyan regression, there existed an isolated Early Bakinsky basin and a late Bakinsky (level up to 20 m) drainage basin (about 400 ka BP). The Venedian (Mishovdag) regression divided the Baku and Urundzhik (Middle Neopleistocene, up to −15 m) transgressions at the end of the early - beginning of the late Pleistocene (basin area - 336 thousand km²). A large deep Cheleken regression (up to −20 m), corresponding to the optimum of the Likhvin interglacial (350-300 thousand years ago), was noted between the marine Urundzhik and Khazar deposits. In the Middle Neopleistocene, there were basins: the Early Khazar Early (200 thousand years ago), the Early Khazar Middle (level up to 35-40 m), and the Early Khazar Late. In the Late Neopleistocene, there was an isolated Late Khazar basin (level up to −10 m, 100 ka), after which a small Cherniyarsk regression of the second half - the end of the Middle Pleistocene (thermoluminescent dates 122-184 ka) occurred, in in turn, replaced by the Girkan (Gyurgyan) basin.

The deep long-term Atelian regression of the mid-late Pleistocene at the initial stage had a level of −20 - −25 m, at the maximum stage −100 - −120 m, at the third stage - −45 - −50 m. At the maximum, the basin area is reduced to 228 thousand km² ... After atelier regression (−120 - −140 m), approx. 17 thousand liters n. the early Khvalynian transgression began - up to + 50 m (the Manych-Kerch Strait was functioning), which was interrupted by the Elton regression. The Early Khvalynian II basin (level up to 50 m) was replaced at the beginning of the Holocene by a short-term Enotai regression (from −45 to −110 m), coinciding in time with the end of the Preboreal and the beginning of the Boreal. Enotaevskaya regression was replaced by late Khvalynian transgression (0 m). The late Khvalynian transgression was replaced in the Holocene (about 9-7 thousand years ago or 7.2-6.4 thousand years ago) by the Mangyshlak regression (from -50 to -90 m). The Mangyshlak regression was replaced in the first phase of interglacial cooling and humidification (Atlantic period) by the Novocaspian transgression. The Novocaspian basin was brackish water (11-13 ‰), warm water and isolated (level up to −19 m). At least three cycles of transgressive-regressive phases in the development of the Novo-Caspian basin have been recorded. The Dagestan (Gousan) transgression previously belonged to the initial stage of the New Caspian epoch, however, the absence of the leading Novocaspian form in its sediments Cerastoderma glaucum (Cardium edule) provides a basis for its separation into an independent transgression of the Caspian. Izberbash regression, separating the Dagestan and the New Caspian transgressions of the Caspian proper, occurred in the interval between 4.3 and 3.9 thousand years ago. Judging by the structure of the Turali section (Dagestan) and the data of radiocarbon analysis, transgressions were recorded twice - about 1900 and 1700 years ago.

Anthropological and cultural history of the Caspian Sea

Shipping

Shipping is well developed in the Caspian Sea. Ferry services operate on the Caspian Sea, in particular, Baku - Turkmenbashi, Baku - Aktau, Makhachkala - Aktau. The Caspian Sea has a shipping connection with Sea of ​​Azov across the Volga, Don and Volga-Don canal.

Fishing and seafood production

Fishing (sturgeon, bream, carp, pike perch, sprat), caviar and 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 is flourishing in the Caspian Sea.

Recreational resources

The natural environment of the Caspian coast with sandy beaches, mineral waters and curative mud in the coastal area creates good conditions for recreation and treatment. At the same time, in terms of the development of resorts and tourism industry, the Caspian coast is noticeably inferior to the Black Sea coast of the Caucasus. However, in last years the tourism industry is actively developing on the coasts of Azerbaijan, Iran, Turkmenistan and Russian Dagestan. A resort area in the Baku region is actively developing in Azerbaijan. At the moment, a world-class resort has been created in Amburan, another modern tourist complex is being built in the area of ​​the village of Nardaran, recreation in the sanatoriums of the villages of Bilgah and Zagulba is very popular. A resort area is also being developed in Nabran, in the north of Azerbaijan. However, high prices in general low level service and lack of advertising lead to the fact that there are almost no foreign tourists in the Caspian resorts. The development of the tourism industry in Turkmenistan is hindered by a long-term policy of isolation, in Iran - by Sharia law, which makes it impossible for foreign tourists to spend mass vacations on the Caspian coast of Iran.

Ecological problems

Environmental problems of the Caspian Sea are associated with water pollution as a result of oil production and transportation on the continental shelf, the influx of pollutants from the Volga and other rivers flowing into the Caspian Sea, the life of coastal cities, as well as flooding of certain objects due to the rise in the level of the Caspian Sea. Predatory hunting of sturgeon and their caviar, rampant poaching lead to a decrease in the number of sturgeon and to forced restrictions on their production and export.

Legal status

After the collapse of the USSR, the division of the Caspian Sea for a long time was and still remains the subject of unresolved disagreements related to the division of the Caspian shelf resources - oil and gas, as well as biological resources. For a long time, negotiations were going on between the Caspian states on the status of the Caspian Sea - Azerbaijan, Kazakhstan and Turkmenistan insisted on dividing the Caspian along the median line, Iran - on dividing the Caspian by one fifth between all the Caspian states.

With regard to the Caspian, the key is the physical and geographical circumstance that it is a closed inland water body that does not have a natural connection with the World Ocean. Accordingly, the norms and concepts of international maritime law, in particular, the provisions of the 1982 UN Convention on the Law of the Sea, should not be automatically applied to the Caspian Sea. Based on this, in relation to the Caspian it would be inappropriate to apply such concepts as "territorial sea", "exclusive economic zone", "continental shelf", etc.

The current legal regime of the Caspian Sea was established by the Soviet-Iranian treaties of 1921 and 1940. These treaties provide for freedom of navigation throughout the sea, freedom of fishing with the exception of ten-mile national fishing zones and a ban on ships flying the flag of non-Caspian states in its waters.

Negotiations on the legal status of the Caspian are ongoing.

Delimitation of sections of the seabed of the Caspian Sea for the purpose of subsoil use

The Russian Federation signed an agreement with Kazakhstan on delimiting the bottom of the northern part of the Caspian Sea in order to exercise sovereign rights to subsoil use (dated July 6, 1998 and the Protocol to it dated May 13, 2002), an agreement with Azerbaijan on delimiting adjacent sections of the bottom of the northern part of the Caspian Sea (dated September 23, 2002), as well as the trilateral Russian-Azerbaijani-Kazakh agreement on the junction point of the delimitation lines of adjacent sections of the Caspian Sea bottom (dated May 14, 2003), which established geographical coordinates dividing lines limiting the seabed areas within which the parties exercise their sovereign rights in the field of exploration and production of mineral resources.

Which countries are located on the shores of the Caspian Sea can not be listed by all.

Countries on the shores of the Caspian Sea

Caspian Sea is the largest inland body of water on our planet. It also has no outflow. The Caspian Sea is classified in different ways: as the world's largest lake and as a full-fledged sea. Its surface is 371,000 km 2 (143,200 mi 2), and the volume of the reservoir is 78,200 km 3. The maximum depth is 1025 m. The salinity of the sea is about 1.2% (12 g / l). The sea level is constantly fluctuating from tectonic movements and high temperature air. Today it is 28 m below sea level.

Even the ancient inhabitants who inhabited the coast of the Caspian Sea perceived it as a real ocean. It seemed to them limitless and very large. The word "Caspian" comes from the language of these peoples.

Which countries are located on the shores of the Caspian Sea?

The waters of the sea wash the shores of 5 coastal states. This:

• Russia... The coastal zone covers Kalmykia, Dagestan and the Astrakhan region in the northwest and west. The coastline is 695 km long.
• Kazakhstan... The coastal zone covers the east, north and north-east of the state. The coastline is 2320 km long.
• Turkmenistan... The coastal zone covers the southeast of the country. The coastline is 1200 km long.
• Iran... The coastal zone covers the southern part of the state. The coastline is 724 km long.
• Azerbaijan... The coastal zone covers the southwest of the country. The coastline is 955 km long.

In addition, this water volume is the main object of the International Society, since there are huge reserves of natural gas and oil. The Caspian Sea is only 700 miles long, but contains six hydrocarbon basins. Most of them have not been mastered by humans.

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 about 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 conventionally divided by physical and geographical conditions into 3 parts - the North Caspian, the Middle Caspian and the South Caspian. The conditional border between the North and Middle Caspian Sea we pass along the Chechen line (Island)- Tyub-Karagan Cape, between the Middle and South Caspian - along the Zhilaya line (Island)- Gan-Gulu (cape)... The area of ​​the North, Middle and South Caspian Sea is 25, 36, 39 percent, respectively.

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 on the southwestern coast of the Caspian Sea before our era. Throughout the history of its existence, the Caspian Sea had about 70 names among different tribes and peoples: the Hyrcanian Sea; Khvalynskoe sea or Khvalisskoe sea - an ancient Russian name derived from the name of the inhabitants of Khorezm who traded in the Caspian - khvalis; Khazar Sea - name in Arabic (Bahr al-Khazar), Persian (Daria-e Khazar), Turkish and Azerbaijani (Khazar denizi) languages; Abeskun Sea; Sarayskoe sea; Derbent Sea; Sihai and other names. In Iran, the Caspian Sea is still called the Khazar or Mazenderan Sea. (by the name of the people inhabiting the coastal province of Iran of the same name).

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 and smooth. In the northern part, the coastline is cut 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. The eastern coast is dominated by limestone shores adjacent to semi-deserts and deserts. The most winding shores are on the western coast in the area of ​​the Absheron Peninsula and on the eastern coast in the area of ​​the Kazakh Bay and Kara-Bogaz-Gol.

Large peninsulas of the 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 a total area of ​​about 350 square kilometers. The largest islands: Ashur-Ada, Garasu, Gum, Dash, Zira (Island), Zyanbil, Kur Dashy, Khara-Zira, Sengi-Mugan, Chechen (Island), Chygyl.

Large bays of the Caspian Sea: Agrakhan Gulf, Komsomolets (bay) (formerly Dead Kultuk, formerly the Gulf of Tsarevich), Kaidak, Mangyshlak, Kazakh (bay), Turkmenbashi (bay) (formerly Krasnovodsk), Turkmen (bay), Gizilagach, Astrakhan (bay), Gyzlar, Girkan (formerly Astarabad) and Anzeli (formerly Pahlavi).

Near the eastern coast is the salt lake Kara Bogaz Gol, which until 1980 was a lagoon-bay 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 several meters. In 1992, the strait was restored, along it the water leaves the Caspian Sea to Kara-Bogaz-Gol and evaporates there. Every year, 8-10 cubic kilometers of water flows from the Caspian Sea to Kara-Bogaz-Gol (according to other sources - 25 thousand kilometers) and about 150 thousand tons of salt.

130 rivers flow into the Caspian Sea, 9 of which have delta-shaped estuaries. Large rivers flowing into the Caspian Sea - Volga, Terek (Russia), Ural, Emba (Kazakhstan), Kura (Azerbaijan), Samur (border of Russia with Azerbaijan), Atrek (Turkmenistan) other. The largest river flowing into the Caspian Sea is 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 runoff of the Caspian Sea.

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 territory of enclosed water basins. The length of the Caspian Sea basin from north to south is about 2500 kilometers, from west to east - about 1000 kilometers. The Caspian Sea basin covers 9 states - Azerbaijan, Armenia, Georgia, Iran, Kazakhstan, Russia, Uzbekistan, Turkey and Turkmenistan.

The Caspian Sea washes the shores of five coastal states:

• Of Russia (Dagestan, Kalmykia and Astrakhan region)- in the west and north-west, the length of the coastline is 695 kilometers
• Kazakhstan - in the north, north-east 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 is 724 kilometers
• Azerbaijan - in the south-west, the length of the coastline is 955 kilometers

The largest city - port on the Caspian Sea - Baku, the capital of Azerbaijan, which is located in the southern part of the Absheron Peninsula and employs 2,070 thousand people (2003) ... Other major Azerbaijani Caspian cities- Sumgait, 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 village of oil workers Neftyanye Kamni, whose structures are located 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 coast 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 coast of the Krasnovodsk Bay - the Turkmen city of Turkmenbashi, formerly Krasnovodsk. Several Caspian cities are located in the southern (Iranian) coast, the largest of them is Anzali.

The area and volume of water in the Caspian Sea varies significantly depending on the fluctuations in the water level. With 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 above its surface. 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 according to the bathygraphic curve, is 208 meters. At the same time, the northern part of the Caspian is shallow, its maximum depth does not exceed 25 meters, and the average depth is 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 fluctuation have been carried out since 1837, during which 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 been increasing and in 1995 reached the level of -26.7 m, since 1996 there has been a downward trend again. Scientists associate the reasons for the change in the water level of the Caspian Sea with climatic, geological and anthropogenic factors.

Water temperature is subject to significant latitudinal changes, most pronounced in winter, when the temperature varies 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 difference in water temperature is about 10 ° C. For shallow areas with depths less than 25 m, the annual amplitude can reach 25 - 26 ° C. On average, the water temperature near the western coast is 1 - 2 ° C higher than that of the eastern one, and in the open sea the water temperature is 2 - 4 ° C higher than that of the coasts. By 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 southern and eastern, which is especially well traced in the Middle Caspian. Two stable quasi-latitude zones can be distinguished, where 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 sill, from 7 to 10 ° C. During this period, the least cooled 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 a faster warming up 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 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. Spring water warming evens out the horizontal gradients, and the temperature difference between the coastal areas and open sea does not exceed 0.5 ° C. The heating of the surface layer, which begins in March, disturbs the uniformity in the temperature distribution with depth. In June-September, there is horizontal uniformity in the temperature distribution in the 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 northwestern winds prevailing in the summer season. The wind in this direction causes the outflow of warm surface waters from the coast and the rise of colder waters from the intermediate layers. The upwelling begins in June, but it reaches its highest intensity in July-August. As a result, a decrease in temperature is observed on the water surface. (7 - 15 ° C)... Horizontal temperature gradients reach 2.3 ° C at the surface and 4.2 ° C at a depth of 20 m. The upwelling focus is gradually shifting from 41 - 42 ° N. in June to 43 - 45 ° N in September. Summer upwelling is of 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 layer of temperature jump begins, which is most pronounced 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 jump layer are very significant and can reach several degrees per meter. In the middle part of the sea, as a result of the drive off the eastern coast, the shock layer rises close to the surface. Since in the Caspian Sea there is no stable baroclinic layer with a large supply of potential energy, similar to the main thermocline of the World Ocean, then with the termination of the prevailing winds causing upwelling, and with the onset of autumn-winter convection in October-November, a rapid restructuring of the temperature fields to the winter regime occurs. In the open sea, the water temperature in the surface layer drops in the middle to 12-13 ° C, in the southern part to 16-17 ° C. In the vertical structure, the shock layer is eroded due to convective mixing and disappears by the end of November.

The salt composition of the waters of the enclosed 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 of sea waters, an increase in the relative amount of carbonates, sulfates, calcium, which are the main components in the chemical composition of river waters. The most conserved ions are potassium, sodium, chlorine and magnesium. The least conservative are calcium and bicarbonate ions. In the Caspian, the content of calcium and magnesium cations is almost two times higher than in the Sea of ​​Azov, and the content of sulfate anions 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 salty bays-kultuk can reach 60 - 100 g / kg. In the Northern Caspian, during the entire ice-free period from April to November, a salinity front of a quasi-latitude location is observed. The greatest desalination associated with the spread of river runoff over the sea area is observed in June. The formation of the salinity field in the North Caspian is greatly influenced by 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 southerly and easterly. Salinity increases slightly with depth. (by 0.1 - 0.2 psu units)... In the deep-water part of the Caspian Sea, in the vertical salinity profile, there are characteristic isohaline troughs and local extrema in the area of ​​the eastern continental slope, which indicate the processes of bottom sliding of waters salinizing in the eastern shallow waters of the South Caspian. Salinity is also highly dependent on sea level and (which is interconnected) from the volume of continental runoff.

The relief of the northern part of the Caspian is a shallow undulating plain with banks and accumulative islands, the average depth of the North Caspian is about 4 - 8 meters, the maximum depth does not exceed 25 meters. The Mangyshlak sill separates the North Caspian from the Middle. The Middle Caspian is quite deep, the water depth in the Derbent depression reaches 788 meters. The Absheron sill separates the Middle and South Caspian. The South Caspian Sea is considered to be 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, in some areas there is an outcrop of bedrocks.

The climate of the Caspian Sea is continental in the northern part, temperate in the middle and subtropical in the southern part. In winter, the average monthly temperature of the Caspian Sea 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 highest temperature recorded on the east coast is 44 degrees.

Average annual rainfall is 200 millimeters per year, 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 is in the area of ​​the Absheron Peninsula and in the eastern part of the South Caspian - 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, in the wind rose prevail north winds... In the autumn and winter months, the winds increase, the speed of the winds often reaches 35-40 meters per second. The most windy areas are the Apsheron Peninsula and the vicinity of Makhachkala - Derbent, where the highest wave was recorded - 11 meters.

The circulation of waters in the Caspian Sea is associated with runoff and winds. Since most of the runoff is in the North Caspian, northern currents prevail. The intense northern current carries water from the North Caspian along the western coast to the Absheron Peninsula, where the current splits into two branches, one of which moves further along the western coast, the other goes to the Eastern Caspian.

The fauna of the Caspian Sea is represented by 1810 species, of which 415 are vertebrates. There are 101 species of fish registered in the Caspian world, and most of the world's sturgeon stocks, as well as freshwater fish such as roach, carp, and pike perch, are concentrated in the Caspian world. The Caspian Sea is a habitat for such fish as carp, mullet, sprat, kutum, bream, salmon, perch, pike. The Caspian Sea is also home to 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, charovy and others, and of flowering plants - zostera and ruppia. By origin, the flora belongs mainly to the Neogene age, however, some plants were introduced into the Caspian Sea by humans deliberately or on the bottoms of ships.