Geography of Lake Baikal. General information

Origin of Lake Baikal

Kochetova N.S.

deepest lake

On Earth, only 6 lakes with fresh water have a depth of more than 500 meters.

Baikal (Russia) - 1637 m

Tanganyika (Africa) - 1435 m

Caspian Sea - 1025 m

Nyasa (Africa) - 706 m

Issyk-Kul (Kyrgyzstan) - 702 m

B. Slave (Canada) - 614 m

Kivu (Africa) - 496 m

Upper (USA) - 393 m

Geneva (Switzerland) - 310 m

Lake Baikal is located in the southern part Eastern Siberia.

This deepest lake planets.

largest natural reservoir fresh water.

Baikal is of rift origin.

The rift zone extends from Mongolia to Yakutia, its length is 2500 km . The maximum depth of the Baikal Rift Basin is about 9.6 km , including the maximum depth of the lake.

Baikal is located on the border of the connection of two platforms of the earth's crust - the Siberian and Central Asian folded belt.

Under Baikal in the mantle of the Earth there is an ascending flow of magma. The current rises up to the fault and spreads under it to the sides, stretching the earth's crust.

Long-term observations, including data from space stations, have shown that Baikal basin not yet finalized . It continues to expand at a rate of several millimeters per year. Scientists speculate that in hundreds of millions of years, this process will lead to the splitting of the Asian continent at the site of Baikal and the formation of an ocean .

The territory of Baikal is a zone of increased seismic hazard. Seismographs record about 2,000 earthquakes a year. The largest in the history of observations is Tsagan earthquake of 1861-1862

Based on the results of long-term observations of seismic activity, scientists have found that large earthquakes in the Baikal-Mongolian region are repeated once every 50-60 years.

There are more than 30 seismic stations with seismographs . With their help, scientists calculated that within the Baikal rift, more than 5 - 8 thousand earthquakes per year . About 2,000 earthquakes a year are recorded directly on Lake Baikal. The work of a seismograph and the registration of earthquakes on a computer can be observed in the Baikal Museum in the village of Listvyanka.

With the help of high-precision observations using satellites, it was found that as a result of the stretching of the earth's crust, the Baikal Basin is expanding at a rate of several millimeters per year. Some scientists suggest that in 100-150 million years these processes can lead to the split of the Asian continent in place of Baikal and the formation of the ocean . Therefore, we can meet, the judgment that despite the ancient age Baikal continues to change, increase in size, which means that it can be argued that it still "young".

Numerous hot springs also testify to the activity of the earth's crust in the Baikal rift zone. mineral water which are located right on the shores of Lake Baikal. The most famous of them are the sources Zmeinaya Bay (Chivyrkuysky Bay), Frolikha spring and Khakusy bay (northeast coast), Goryachinsk district (East Coast). The springs are healing and are used in the treatment of various diseases.

Peculiarity the formation of the Baikal basin - lack of powerful volcanic activity , which usually accompanies the formation of a rift.

Volcanic activity in the area of ​​Lake Baikal during the formation of the rift zone was insignificant. Closest to Baikal volcanoes - Volcanoes of the Tunkinskaya valley, as well as the Kropotkin volcano and the Peretolchin volcano in Eastern Sayan. They are currently not active.

The Baikal basin consists of three independent depressions:

• South Baikal ,
• Middle Baikal, separated by an uplift near Posolskaya Bank,
• Severobaikalskaya, separated from the Srednebaikalskaya by the underwater Academic Ridge, crossing Baikal along the line Olkhon Island - the Ushkany Islands archipelago.

With the development of geophysical methods and the accumulation of knowledge, certain details of the chronological sequence of the formation of Lake Baikal began to appear.

Three stages can be distinguished in the geological history of the Baikal Rift :

• Archeobaikalian covers the time interval 70-30 million years ago. ,
• Proto-Baikal 30.0-3.5 million years ago.
• paleobaikalian from 3.5 million years ago to the present.

When traveling around Lake Baikal in a kayak, the last thing you think about is that now you have 20% of the world's purest fresh water reserves under you.

This section contains basic information about the lake, and links to the Magic of Baikal pages, where you can get more detailed information. In the process of collecting information, I encountered the fact that data from different sources diverge, sometimes significantly. For example, there is still no generally accepted opinion regarding the number of islands on Baikal, the number of rivers flowing into the lake, etc. The origin of the names of capes, islands, bays and other objects is often a mystery shrouded in darkness. I tried to take information from reliable sources and point out the discrepancies and their reasons. Located in Vladivostok recreation center Rus.

Lake Baikal is located in the south of Eastern Siberia. In the form of a crescent being born, Baikal stretched from southwest to northeast between 55°47" and 51°28" north latitude and 103°43" and 109°58" east longitude. The length of the lake is 636 km, the maximum width in the central part is 81 km, the minimum width opposite the Selenga delta is 27 km (between the capes Goly on west bank Baikal and Sredny on the east). Baikal is located at an altitude of 455 m above sea level. Length coastline about 1850 km (excluding part of the coast north of the island Yarki). More than half of the lake's shoreline is under the protection of Lake Baikal environmental organizations.

The area of ​​the water mirror, determined at the water's edge of 454 m above sea level, is 31,470 square kilometers. The maximum depth of the lake is 1637 m, average depth- 730 m. Sometimes in the literature there is a statement that the maximum depth of Baikal is 1642 m. Which value is correct? The answer to this question is somewhat paradoxical - both are correct. The fact is that the measurement error of such depths is about 2%, i.e. 30 meters. Therefore, it is correct to say that the greatest depth of Baikal is 1640 m.

336 permanent rivers and streams flow into Baikal, while half of the water entering the lake comes from the Selenga. flows out of Baikal the only river- Angara. However, the question of the number of rivers flowing into Baikal is rather controversial, most likely there are fewer than 336. There is no doubt that Baikal is the deepest lake in the world, the closest contender for this title, African lake Tanganyika, lags behind by as much as 200 meters. There are 30 islands on Baikal, although, as mentioned above, there is no unanimity on this issue. The largest is Olkhon Island.

Age of Lake Baikal.

The age of the lake is usually given in the literature as 20-25 million years. In fact, the question of the age of Baikal should be considered open, since the use of various methods for determining the age gives values ​​from 20-30 million to several tens of thousands of years. Apparently, the first estimate is closer to the truth - Baikal is really very ancient lake. If we assume that the age of Baikal is indeed several tens of millions of years, then this is the oldest lake on Earth.

It is believed that Baikal arose as a result of the action of tectonic forces. Tectonic processes are still going on, which is manifested in the increased seismicity of the Baikal region.

Origin of name.

Numerous scientific studies have been devoted to the problem of the origin of the word "Baikal", which indicates a lack of clarity in this matter. There are about a dozen possible explanations for the origin of the name. Among them, the most probable is the version of the origin of the name of the lake from the Turkic-speaking Bai-Kul - a rich lake. Of the other versions, two more can be noted: from the Mongolian Baigal - a rich fire and Baigal Dalai - big lake. The peoples who lived on the shores of the lake called Baikal in their own way. Evenks, for example, - Lamu, Buryats - Baigal-Nuur, even the Chinese had a name for Baikal - Beihai - the North Sea.

The Evenk name Lamu - the Sea was used for several years by the first Russian explorers in the 17th century, then they switched to the Buryat Baigal, slightly softening the letter "g" by phonetic replacement. Quite often, Baikal is called the sea, simply out of respect, for its violent temper, for the fact that the far opposite coast is often hidden somewhere in the haze. At the same time, the Small Sea and the Big Sea are distinguished. Small Sea - what is located between north coast Olkhon and the mainland, everything else is the Big Sea.

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Baikal - freshwater lake in the south of Eastern Siberia, it stretched from 53 to 56 ° N. and from 104 to 109°30’ E Its length is 636 km, and the coastline is 2100 km. The width of the lake varies from 25 to 79 km. The total area of ​​the lake (mirror area) is 31,500 sq. km.

Baikal is the deepest lake in the world (1620 m). It contains the largest fresh water reserves on earth - 23 thousand cubic kilometers, which is 1/10 of the world's fresh water reserves. A complete change of such a huge amount of water in Baikal takes 332 years.

This is one of the oldest lakes, its age is 15-20 million years.

336 rivers flow into the lake, including the Selenga, Barguzin, Upper Angara, and only one Angara flows out. Baikal has 27 islands, the largest of which is Olkhon. The lake freezes in January, opens in May.

Baikal lies in a deep tectonic depression and is surrounded by taiga-covered mountain ranges; the area around the lake has a complex, deeply dissected relief. Near Baikal, the band of mountains expands noticeably. The mountain ranges here stretch parallel to one another in the direction from the northwest to the southeast and are separated by hollow-shaped depressions, along the bottom of which rivers flow and in some places there are lakes. The height of most of the ridges of Transbaikalia rarely exceeds 1300 - 1800, but most high ridges reach high values. For example, xr. Khamar-Daban (Sokhor peak) - 2304 m, and the Barguzinsky ridge. about 3000 m.

Tectonic movements continue here even now. This is evidenced by frequent earthquakes in the region of the basin, outcrops of hot springs, and, finally, subsidence of significant sections of the coast.

The waters of Baikal have a blue-green color, are distinguished by exceptional purity and transparency, often even greater than in the ocean: you can clearly see stones lying at a depth of 10-15 m and thickets of greenish algae, and a white disk lowered into the water is visible at a depth of 40 m.
Baikal lies in the temperate zone.

Geography of Lake Baikal.

Lake Baikal is located in the south of Eastern Siberia. In the form of a crescent being born, Baikal stretched from southwest to northeast between 55°47′ and 51°28′ north latitude and 103°43′ and 109°58′ east longitude. The length of the lake is 636 km, the maximum width in the central part is 81 km, the minimum width opposite the Selenga delta is 27 km. Baikal is located at an altitude of 455 m above sea level. The length of the coastline is about 2000 km. The area of ​​the water mirror, determined at the water's edge of 454 m above sea level, is 31,470 square kilometers. The maximum depth of the lake is 1637 m, the average depth is 730 m. 336 permanent rivers and streams flow into Baikal, while half of the water entering the lake comes from the Selenga. The only river that flows out of Baikal is the Angara. However, the question of the number of rivers flowing into Baikal is rather controversial, most likely there are less than 336 of them. There is no doubt that Baikal is the deepest lake in the world, the closest contender for this title, the African Lake Tanganyika, lags behind by as much as 200 meters. There are 22 islands on Baikal, although, as mentioned above, there is no unanimity on this issue. Most large island— Olkhon.

Age of Lake Baikal.

The age of the lake is usually given in the literature as 20-25 million years. In fact, the question of the age of Baikal should be considered open, since the use of various methods for determining the age gives values ​​from 20-30 million to several tens of thousands of years. Apparently, the first estimate is closer to the truth - Baikal is indeed a very ancient lake.
It is believed that Baikal arose as a result of the action of tectonic forces. Tectonic processes are still going on, which is manifested in the increased seismicity of the Baikal region. If we assume that the age of Baikal is indeed several tens of millions of years, then this is the oldest lake on Earth.

Origin of name.

Numerous scientific studies have been devoted to the problem of the origin of the word "Baikal", which indicates a lack of clarity in this matter. There are about a dozen possible explanations for the origin of the name. Among them, the most probable is the version of the origin of the name of the lake from the Turkic-speaking Bai-Kul - a rich lake. Of the other versions, two more can be noted: from the Mongolian Baigal - a rich fire and Baigal Dalai - a large lake. The peoples who lived on the shores of the lake called Baikal in their own way. Evenks, for example, - Lamu, Buryats - Baigal-Nuur, even the Chinese had a name for Baikal - Beihai - the North Sea.

The Evenki name Lamu - the Sea was used for several years by the first Russian explorers in the 17th century, then they switched to the Buryat Baigal, slightly softening the letter "g" by phonetic replacement. Quite often, Baikal is called the sea, simply out of respect, for its violent temper, for the fact that the far opposite shore is often hidden somewhere in the haze ... At the same time, the Small Sea and the Big Sea are distinguished. The Small Sea is what is located between the northern coast of Olkhon and the mainland, everything else is the Big Sea.

Baikal water.

Baikal water is unique and amazing, like Baikal itself. It is unusually transparent, pure and saturated with oxygen. In not so ancient times, it was considered healing, with its help, diseases were treated. In spring, the transparency of Baikal water, measured using the Secchi disk (a white disk with a diameter of 30 cm), is 40 m (for comparison, in the Sargasso Sea, which is considered the standard of transparency, this value is 65 m). Later, when a massive algae bloom begins, the transparency of the water decreases, but in calm weather, the bottom can be seen from a boat at a fairly decent depth. This high transparency is due to the fact that Baikal water, due to the activity of living organisms living in it, is very weakly mineralized and close to distilled. The volume of water in Baikal is about 23 thousand cubic kilometers, which is 20% of the world's fresh water reserves.

Climate.

The climate in Eastern Siberia is sharply continental, but the huge mass of water contained in Baikal and its mountainous surroundings create an unusual microclimate. Baikal works like a big thermal stabilizer - in winter it is warmer in Baikal, and in summer a little cooler than, for example, in Irkutsk, located at a distance of 60 km from the lake. The temperature difference is usually around 10 degrees. A significant contribution to this effect is made by forests growing on almost the entire coast of Lake Baikal.

Baikal's influence is not limited to regulation temperature regime. Due to the fact that evaporation cold water from the surface of the lake is very insignificant, clouds cannot form over Baikal. In addition, the air masses that bring clouds from the land heat up when passing the coastal mountains, and the clouds dissipate. As a result, the sky over Baikal is clear most of the time. This is also evidenced by the numbers: the number of hours of sunshine in the area of ​​Olkhon Island is 2277 hours (for comparison, on the Riga seashore in 1839, in Abastumani (Caucasus) - 1994). You should not think that the sun always shines over the lake - if you are not lucky, then you can run into one or even two weeks of disgusting rainy weather even in the sunny place Baikal - on Olkhon, but this is extremely rare.

The average annual water temperature on the surface of the lake is +4°C. Near the coast in summer the temperature reaches +16-17°C, in shallow bays up to +22-23°C.

Wind and waves.

The wind on Baikal blows almost always. More than thirty local names of winds are known. This does not mean at all that there are so many different winds on Baikal, just that many of them have several names. The peculiarity of the Baikal winds is that almost all of them almost always blow along the coast and there are not as many shelters from them as we would like.

Prevailing winds: northwest, often called mountain winds, northeast (barguzin and verkhovik, also known as angara), southwest (kultuk), southeast (shelonnik). The maximum wind speed recorded on Lake Baikal is 40 m/s. In the literature, there are also large values ​​- up to 60 m / s, but there is no reliable evidence for this.

Where there is wind, there, as you know, there are waves. I note right away that the opposite is not true - the wave can be even with complete calm. Waves on Lake Baikal can reach a height of 4 meters. Sometimes values ​​​​of 5 and even 6 meters are given, but this is most likely an estimate “by eye”, which has a very large error, as a rule, towards overestimation. The height of 4 meters was obtained using instrumental measurements in the open sea. The excitement is strongest in autumn and spring. In the summer on Lake Baikal, strong excitement is rare, and calm often occurs.

Baikal is one of the giant closed reservoirs on the planet. No lake can compare with it in depth. Baikal has a significant share of the world's fresh water reserves. Its flora and fauna are extremely diverse. Baikal water is remarkable for its amazing purity and transparency. The history of the study of the lake has been going on for more than three centuries, but there are still many mysteries related to its age and the reasons for its origin.

Geographic location

Baikal is located in the southern part of Eastern Siberia, on the border separating the territories Irkutsk region and the Republic of Buryatia. The lake is located in a crescent-shaped hollow surrounded by rocks and hills. Its length is 620 km, the width varies from 24 to 79 km. The east coast is less rocky and steep than the west coast. The area of ​​the water surface is comparable to the territories of some European states. It is 31722 km 2. According to this indicator, Baikal ranks seventh on the planet. Only a few largest lakes the American and African continents surpass it in terms of water surface area.

Depth

Baikal was the reason for its unique characteristics. Scientific studies confirm that this lake is the deepest in the world. It is worth taking into account that its water mirror is located at an altitude of 456 m above sea level. Hydrographic expeditions recorded and mapped maximum value the depth of the lake is 1642 m. Consequently, the bottom point, which is extremely remote from the surface, is located 1187 m below the level of the world ocean. This record figure allows Baikal to be included in the list of the most deep depressions on the planet. It can only be compared with Lake Tanganyika in Central Africa and the Caspian Sea, which is officially considered a closed body of water, since it does not have access to the oceans. Their depth exceeds 1000 m.

Water volume

The long history of Baikal exploration has brought many surprises. It has been proven that it has the largest reserves of lake fresh water in the world. Its volume is 23615 km3. This is about 20% of the world's reserves. Only the volume of the Caspian Sea exceeds given value, but the water in it is salty, unlike Baikal. The history of the emergence and development of special flora and fauna has made the lake a unique ecological system. The fresh water of Lake Baikal is distinguished by its rare purity. The lake is a world record holder not only in its quantity, but also in quality.

Water characteristics

In the history of Baikal special place occupies the study of its flora and fauna. As it turned out, the water of the lake owes its unique purity to the local flora and fauna. All elements of the natural system are interconnected and influence each other. Baikal water is highly saturated with oxygen. It contains a negligible amount of dissolved minerals and organic impurities. Even pollution resulting from human activities does not lead to a significant deterioration in water quality. The development of industry and the tourism industry does not go unnoticed for the ecological state of the lake. However, in terms of its characteristics, the water remains close to the distillation product obtained in the laboratory. One of the reasons for its amazing purity lies in the vital activity of a microscopic crustacean. This representative of the fauna played an important role in the history of Baikal. The crustacean reproduces in huge numbers and absorbs organic matter, naturally purifying the water of the lake.

Origin hypotheses

The history of the origin of Baikal causes some controversy. The lake is located in a large depression that appeared at the site of a break in the earth's crust. The emergence of Baikal is due to tectonic causes. Some researchers put forward a version that the depression was formed as a result of the interaction of two continental plates - the Eurasian and Hindustan. Others argue that the lake is located in a transform fault zone. This type of rupture of the earth's crust occurs along the boundary of the lithospheric plate. In addition, there is a hypothesis that is poorly substantiated from a scientific point of view about the appearance of vacuum pockets due to the ejection of volcanic rock to the surface. According to this version, this caused the depression to subside.

The controversy continues. However, increased seismic activity in this region leaves no doubt about the tectonic nature of the reservoir.

Age

The opinions of scientists differ greatly about the duration of the history of Baikal. The traditional version claims that the lake has existed for over 25 million years. This hypothesis raises some doubts. Usually lakes remain in their original form for no more than 10-15 thousand years. After that, due to the accumulation of a significant amount of silt at the bottom, they turn into swamps. A natural question arises: why, despite many millions of years of history, Baikal did not suffer the same fate?

Exists alternative version, indirectly confirmed by some studies. According to her, the age of the lake is about 8 thousand years. Of interest is the huge discrepancy between traditional and alternative theories. At present, the question of the age of Baikal remains open.

Freezing

Even in summer, the water in the lake does not heat up above 10°C. Maximum temperature, noted throughout the history of observations, is 23°C. In winter, the water mirror freezes almost completely. The thickness of the ice reaches 1 m, and in some places it can reach up to 2 m. winter period the fish in the lake do not suffer from lack of oxygen. Due to severe frosts, cracks several meters wide are formed in the ice. Their length is 10-30 km. Through the cracks, water is saturated with oxygen. It saves from death a large number of fish. The period of complete freezing of the lake usually lasts from January to May. Passenger and cargo navigation starts in June and ends in September.

Flora and fauna

About half of the species of living organisms living in Baikal are not found anywhere else on the planet. This fact is explained by the isolation and antiquity of the ecological system of the lake. According to scientists, the Baikal fauna consists of 2600 species of animals. The reason for this diversity is the high concentration of oxygen in the water. This makes the lake a favorable habitat for all representatives of the animal world. The presence of a significant amount of oxygen persists even at great depths.

Of the fish living in the reservoir, the most famous is He has become in some way a symbol of the lake. The water column is inhabited by hundreds of species of flatworms, molluscs and crustaceans. At the bottom there are sponges that cover the stones with a continuous growth. They serve as a refuge for many living organisms.

Settlement

The history of the development of Lake Baikal began around the 2nd century BC. The first mention of the lake is contained in a Chinese manuscript of that era. According to archaeologists, 3 thousand years ago, the Baikal region was inhabited by Mongoloid tribes, the ancestors of modern Evenks. In the early Middle Ages, a nationality appeared on the territory of southern Siberia, which was called "guligan" in Chinese written sources. Its representatives were engaged in cattle breeding and agriculture, they knew how to smelt metals. In the 17th century, the formation of the Buryat people began from the Mongol-speaking tribes that migrated to southern Siberia from the west.

The Russian history of the discovery of Baikal is associated with the name of the Cossack Kurbat Ivanov. The expedition under his leadership reached the lake in 1643. The reports received by the tsarist government about the wealth of this region predetermined further development history of Baikal. The lake was briefly described in 1665 by the famous archpriest Avvakum, who visited its shores on his way to exile.

Research

At the beginning of the 18th century, there were geographic Maps Baikal. By order of Peter I, a scientific expedition headed by physician Daniel Messerschmitt was sent to Siberia. It became the source of the first reliable information about the lake and its environs. The contribution to the study of Baikal was made by scientists who were part of the Great Northern Expedition led by They made detailed description lakes and collected extensive information about its flora and fauna.

The first hydrometeorological stations on Baikal were founded in the second half of the 19th century. Their task was to conduct continuous monitoring of fluctuations in the temperature of the surface of the lake and changes in the water level in it. In those years, the study of the bottom relief was also initiated.

Climate

In addition to many other unique features, Baikal is known for its unusual weather conditions. The rocky terrain and the presence of a giant body of water in the lake soften the East Siberian continental climate. The air temperature in the vicinity of Lake Baikal is stable. Summer in coastal zone on average, it is cooler than the surrounding areas, and there are no severe frosts in winter. It is characterized by a long autumn and a late onset of spring.

Baikal(bur. Baigal dalai, Baigal nuur) - lake tectonic origin in the southern part of Eastern Siberia, the deepest lake in the world and the largest (by volume) reservoir of watery fresh water. It contains about 19% of the global supply of fresh water. The lake is located in the rift plain in Eastern Siberia on the border of the Irkutsk region and the Republic of Buryatia. 336 rivers flow into it, many of which are the Selenga, Upper Angara, Barguzin and others, and one river flows out - the Angara.

Information about Baikal:

Geographical location and dimensions of the basin

Baikal is located in the center of Asia, in Russia, on the border of the Irkutsk region and the Republic of Buryatia. The lake stretches from northeast to southwest for 620 km in the form of a huge crescent. The width of Lake Baikal ranges from 24 to 79 km. There is no other deepest lake on earth. The bottom of Baikal is 1167 meters below the level of the World Ocean, and the mirror of its waters is 453 meters higher.

The area of ​​​​the aquatic surface is 31,722 km² (excluding islands), which is approximately equal to the area of ​​\u200b\u200bsuch states as Belgium, the Netherlands or Denmark. Baikal ranks sixth among the largest lakes in the world in terms of the area of ​​its water surface.

The lake is located in a specific basin, surrounded on all sides by mountain ranges and hills. With all this, the western coast is rocky and steep, the relief east coast- more gentle (in some places the mountains recede from the coast for 10 km).

Depth

Baikal is the deepest lake on the planet Earth. Modern meaning the greatest depth of the lake - 1637 m - was established in 1983 by L.G. Kolotilo and A.I. Sulimov during the performance of hydrographic work by the expedition of the GUNiO of the USSR Ministry of Defense at the point with coordinates 53 ° 14 "59" N. latitude. 108°05"11" E

The greatest depth was mapped in 1992 and proved in 2002 as a result of a joint Belgian-Spanish-Russian project to create the latest bathymetric map of Baikal, when the depths were digitized at 1,312,788 points of the lake’s water area (the depth values ​​were obtained as a result of recalculation acoustic sounding data combined with additional bathymetric information, including echolocation and seismic profiling; one of the creators of the discovery of the greatest depth, L.G. Kolotilo, was a participant in this project).

If we take into account that the water surface of the lake is located at an altitude of 453 m above sea level, then the lower point of the basin lies 1186.5 m below the level of the world ocean, which makes the Baikal bowl also one of the deepest continental depressions.

The average depth of the lake is also very large - 744.4 m. It exceeds greatest depths many very deep lakes.

Apart from Baikal, only two lakes on Earth have a depth of more than 1000 meters: Tanganyika (1470 m) and the Caspian Sea (1025 m). According to some data, the subglacial Lake Vostok in Antarctica has a depth of more than 1200 m, but it must be taken into account that this subglacial “lake” is not a lake in the sense that we are used to, because there are four kilometers of ice above the water and it is a kind of closed container, where the water is under tremendous pressure, and the "surface" or "level" of water in different parts of this "lake" differs by more than 400 meters. Consequently, the concept of "depth" for the subglacial Lake Vostok is fundamentally different from the depth of "ordinary" lakes.

Water volume

Water reserves in Baikal are huge - 23,615.39 km³ (about 19% of global fresh water reserves - in all fresh lakes the world contains 123 thousand km³ of water). In terms of water reserves, Baikal occupies the 2nd place in the world among lakes, second only to the Caspian Sea, but the water in the Caspian Sea is salty. There is more water in Baikal than in all 5 Great Lakes taken together, and 25 times more than in Lake Ladoga.

Tributaries and runoff

336 rivers and streams flow into Baikal, but this number takes into account only constant tributaries. The largest of them are Selenga, Upper Angara, Barguzin, Turka, Snezhnaya, Sarma. One river flows out of the lake - the Angara.

Water characteristics

Baikal water is very transparent. The main characteristics of Baikal water can be briefly described as follows: it contains very few dissolved and suspended mineral substances, negligible organic impurities, and a lot of oxygen.

The water in Baikal is cool. The temperature of the surface layers even in summer does not exceed +8…+9°C, in some bays - +15°C. The temperature of the deep layers is about +4°C. Only in the summer of 1986 the temperature surface water in the northern part of Baikal rose to a record 22-23°C.

The water in the lake is so transparent that individual pebbles and various objects can be seen at a depth of 40 m. At this time, the Baikal water is blue. In summer and autumn, when a mass of plant and animal organisms develop in the water warmed by the sun, its transparency drops to 8-10 m, and the color becomes blue-green and green. Pure and clearest water Baikal contains so few mineral salts (96.7 mg/l) that it can be used instead of distilled water.

The freezing period is on average January 9 - May 4; Baikal freezes completely, not counting a small, 15-20 km long section located at the source of the Angara. The sailing period for passenger and cargo ships is usually from June to September; research vessels begin navigation right after the ice breaks up the lake and complete it with the freezing of Lake Baikal, in other words, from May to January.

By the end of winter, the ice thickness on Baikal reaches 1 m, and in the bays - 1.5-2 m. severe frost cracks, which have a local name "stanovye cracks", break the ice into separate fields. The length of such cracks is 10-30 km, and the width is 2-3 m. Breaks occur once a year in approximately the same areas of the lake. They are accompanied by a sonorous crack, reminiscent of thunder or cannon shots. It seems to a person standing on the ice that the ice cover is bursting just under his feet and he will currently fall into the abyss. Thanks to the cracks in the ice, the fish in the lake do not die from a lack of oxygen. Baikal ice, in addition, is very transparent, and the sun's rays fall through it, therefore planktonic aquatic plants that produce oxygen rapidly develop in the water. It is possible to follow along the shores of Lake Baikal in winter ice grottoes and splashes.

Baikal ice presents scientists with many mysteries. So, in the 1930s, specialists from the Baikal Limnological Station found unusual forms of ice cover, corresponding only to Baikal. For example, “hills” are cone-shaped ice mounds up to 6 m high, hollow inside. Appearance they resemble ice tents, "open" in the opposite direction from the coast. The hills can be placed separately, and from time to time they form small "mountain ranges". There are also a number of other types of ice on Baikal: “sokuy”, “kolobovnik”, “autumn”.

In addition, in the spring of 2009, satellite images of various parts of Lake Baikal were widely distributed on the Internet, where dark rings. According to scientists, these rings appear due to the rise of deep waters and an increase in the temperature of the surface layer of water in the central part of the ring structure. As a result of this process, an anticyclonic (clockwise) direction appears. In the zone where the direction achieves the highest velocities, the vertical water exchange increases, which leads to accelerated destruction of the ice cover.

Bottom relief

The bottom of Lake Baikal has a pronounced relief. Along the entire coast of Baikal, coastal shallow waters (shelves) and underwater slopes are developed to a greater or lesser extent; the bed of 3 main basins of the lake is expressed; there are underwater banks and even underwater ridges.

The Baikal basin is divided into three basins: Southern, Middle and Northern, separated from each other by 2 ridges - Akademichesky and Selenginsky.

More expressive is the Academic Ridge, which stretches along the bottom of Lake Baikal from Olkhon Island to the Ushkany Islands (which are its most highest part). Its length is about 100 km, highest altitude above the bottom of Lake Baikal 1848 m. The thickness of bottom sediments in Baikal reaches about 6 thousand m, and highest mountains on Earth, with a height of more than 7000 m.

Islands and peninsulas

There are 27 islands on Baikal (Ushkany Islands, Olkhon Peninsula, Yarki Peninsula and others), the largest of them is Olkhon (71 km long and 12 km wide, located almost in the center of the lake near its west coast, area - 729 km², according to other sources - 700 km²), largest peninsula- Holy Nose.

seismic activity

The Baikal region (the so-called Baikal rift zone) is one of the areas with the highest seismicity: earthquakes constantly occur here, the strength of most of which is one or two points on the MSK-64 intensity scale. But there are also strong ones; So, in 1862, during the ten-point Kudarinsky earthquake in the northern part of the Selenga delta, a land area of ​​​​200 km² with 6 uluses, in which 1300 people lived, went under water, and Proval Bay was formed. Strong earthquakes were also recorded in 1903 (Baikal), 1950 (Mondinskoe), 1957 (Muiskoe), 1959 (Middle Baikal). The epicenter of the Middle Baikal earthquake was located at the bottom of Lake Baikal near the village of Sukhaya ( southeast coast). His strength reached 9 points. In Ulan-Ude and Irkutsk, the force of the head shock reached 5-6 points, cracks and minor damage were observed in buildings and structures. The last strong earthquakes on Baikal occurred in August 2008 (9 points) and in February 2010 (6.1 points).

Climate

Baikal winds often raise a storm on the lake. The water mass of Baikal influences the climate of the coastal area. Winter is milder here summer time- cooler. The arrival of spring on Baikal is delayed by 10-15 days compared to the surrounding areas, and autumn is often quite long.

The Baikal region is distinguished by a large total duration of sunshine. For example, in the village of Huge Goloustnoye, it reaches 2524 hours, which is more than in the Black Sea resorts, and is a record for Russia. There are only 37 days in the absence of the sun in the same inhabited Friday, and 48 on the Olkhon Peninsula.

The special features of the climate are justified Baikal winds, which have their own names - barguzin, sarma, verkhovik, kultuk.

Origin of the lake

The origin of Baikal still causes scientific controversy. Scientists usually determine the age of the lake at 25-35 million years. This fact also makes Baikal unique natural object, because most of lakes, separate glacial origin, live an average of 10-15 thousand years, and later they are filled with silty sediments and become swampy.

But there is also a version about the youth of Baikal, put forward by A.V. Tatarinov in 2009, which received circumstantial evidence during the second step of the Mirs expedition to Baikal. Namely, the activity of mud volcanoes at the bottom of Lake Baikal allows scientists to believe that the modern coastal strip of the lake is only 8 thousand years old, and the deep-water part is 150 thousand years old.

Of course, only that the lake is located in a rift basin and is similar in structure, for example, to the Dead Sea basin. Some researchers explain the formation of Baikal by its location in the transform fault zone, others imply the presence of a mantle plume under Baikal, and others explain the formation of the basin by passive rifting as a result of the collision of the Eurasian plate and Hindustan. Be that as it may, the transformation of Baikal continues to this day - earthquakes constantly occur in the lake districts. There are speculations that the subsidence of the basin is associated with the formation of vacuum chambers due to the outpouring of basalts on the surface (Quaternary period).

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