The southern part of the Baltic Sea near the Russian. Baltic Sea - description, photo and old Russian names

BALTIC SEA

Baltic Sea (from antiquity until the 18th century it was known as the "Varangian Sea") - an inland marginal sea, deeply protruding into the mainland. The Baltic Sea is located in northern Europe, belongs to basin of the Atlantic Ocean. The northernmost point of the Baltic Sea is located near the Arctic Circle (65°40"N), the southernmost point is near Wismar (53°45"N).

The westernmost point is located in the Flensburg area (9°10"E), the easternmost point is in the St. Petersburg area (30°15"E)

Square : 415 thousand km².

Depth: average - 52 m, maximum - 459 m.

HISTORY OF THE SEA
The fauna of the North Atlantic is much richer than the Baltic. from the ocean and North Sea only those few species that can adapt to the difference in salinity between the sea and the ocean penetrate into the Baltic. The poverty of the Baltic fauna partly due to the youth of the sea itself. Before the onset of the ice age, there was land on the site of the Baltic Sea. After the passage of the glacier, the basin of the Baltic Sea was filled with melted glacial water, but the resulting lake was not yet connected to the ocean. About 13 thousand years ago, the lake joined the ocean and turned into a sea. This sea is called Yoldiev, since in the bottom sediments of that period many remains of the mollusk ioldia were found. About 9 thousand years ago, the land rose and separated the Yoldian Sea from the ocean. Over time, the rivers desalinated the new lake, and the freshwater mollusk ancilus calyx multiplied in its waters. The lake was named after him. Antsilov. Renewed about 7 thousand years ago, the connection with the ocean again turned the lake into a sea. Its shallow waters were inhabited by the sea mollusk littorina. He gave the sea a new name - Littorina Sea. This sea, which covered a significant part of the Baltic, gradually became shallow. About 5 thousand years ago, the vast Littorina Sea acquired the outlines of the modern Baltic. At this time, the modern Baltic fauna began to form. The tectonic process in the Baltic zone is still going on. After 5 thousand years The Baltic will again separate from the ocean, its waters will be desalinated by river runoff, and a large freshwater lake will form in place of the sea.

The Baltic Sea is one of the youngest seas in the world. It began to form as early as the Devonian period, but was finally formed only after the ice ages. The contours of the sea, the size, the name changed. Currently, tectonic movements are taking place in the Baltic Sea. They formed like giant scales, the axis of which runs along the Gulf of Finland: the bottom of the Gulf of Bothnia rises by several centimeters a year, and the southern coasts sink. For this reason, it is necessary to lengthen the piers of the northern ports. So that the sea does not flood the lowlands of the coasts, embankments are made.

The Baltic Sea is separated from the Atlantic Ocean by the Scandinavian Peninsula and Jutland. It is connected to the North Sea by the wide straits of the Skagerrak and Kattegat, as well as by the narrower straits of Öresun, the Small and Big Belt.

Sea area (excluding islands) 422,700 km2. Compared to other seas, the Baltic is small, but it is 6.5 times larger than the area of Lithuania. Its length is 1800 km. Across the Baltic Sea near Lithuania, about 370 km. Lithuania owns 2% of the sea area.

The deepest place Landsort depression (459 m). The shores of the Baltic Sea are winding, the coasts of Sweden and the Gulf of Finland are strewn with small low rocky islands - skerries. The southern and southeastern shores are more even, low, with wide beaches. There are also such coasts in Lithuania. Almost half of the sea area falls on three large bays - Bothnian, Finnish and Riga. Smaller bays, for example, Gdansk, also protrude into the mainland.

In the southeast there are lagoons called bays: Curonian and Kaliningrad. They are separated from each other by the Sambian Peninsula, known for its largest amber mines.

Salinity sea water is small. In the deeper western part it reaches 11 ppm, off the coast of Lithuania - 6-8 ppm, in the Gulf of Bothnia - only 2 ppm.

They flow into the Baltic Sea about 250 rivers, 500 - 1000 mm of precipitation falls on the sea annually. The level of the Baltic Sea is 14 cm higher than the level of the Atlantic Ocean.

Due to the prevailing southwestern winds, flowing rivers, uneven bottom, the water on the sea surface moves counterclockwise along the coasts. These are coastal currents.

The sea is quite rough. During storms, the height of the waves in the open sea reaches 8 meters, and off the coast 14 meters. The waves of the Baltic Sea are short, therefore more dangerous and cause more damage. In the practically closed Baltic Sea low tides and low tides you could say they don't exist. Large fluctuations in the water level (up to 2 m) are caused due to wind-induced pressure and water surge. Surface layers of water in the southern part of the Baltic Sea in summer they heat up to 23-24 degrees, in the middle part - until 15-17. Water rarely gets warmer in the Gulf of Bothnia 12-14 degrees. Near the Lithuanian coast heat water happens in August - 21-23 degrees. In winter, the water cools down to 2 degrees, and in the Gulf of Bothnia, the Gulf of Finland and the Gulf of Riga, the temperature drops below 0 degrees - the bays freeze. In very cold winters, a thin layer of ice forms in the port of Klaipeda, but the ships crush it, and the currents carry it to the sea.

The vast wealth of the Baltic Sea - fish. It contains about 100 species of fish. There are about 70 of them near the Lithuanian coasts. In the northern part of the Baltic Sea, there are seals. They are also found near the coast of Lithuania. Over the past 10-15 years, the conditions of the flora and fauna in the Baltic Sea have changed a lot: various harmful substances enter the sea, more and more fish are caught, so its resources do not have time to be renewed. Once upon a time, the Baltic Sea became famous thanks to amber. Now found at the bottom of the sea oil, gas, heavy metals, iron, nickel, cobalt, manganese, copper. Used sand and gravel from the bottom of the sea . There are many states around the Baltic Sea, important shipping lanes to America, African countries. There are many major ports: St. Petersburg, Ventspils, Lubeck. There are also many in the Baltic Sea resorts, including the Lithuanian resorts of Palanga and Neringa.

More than 70 million people live in the Baltic Sea basin. Every year, 100,000 tons of various toxic substances enter the sea from cities, industrial production, and agricultural areas through rivers into the sea. Off the coast of Lithuania, the Baltic Sea most pollutes Klaipeda and the rivers belonging to the Nemunas basin. Also, a lot of pollutants come from the atmosphere. The sea also suffers from ships that transport oil products.

November 21, 1981 British tanker Globe Asimi 170 m long swam aground near the port of Klaipeda during a storm and was wrecked. 16.5 thousand tons of fuel oil spilled into the sea and the Curonian Lagoon. It was the biggest environmental disaster in the Baltic Sea.

Baltic Sea - inland, the exchange of water between it and the Atlantic is very slow. The water in the Baltic Sea completely changes only after 30 years. Due to the slow exchange of water and the high amount of pollutants, the Baltic Sea is considered one of the most polluted seas in the world. The situation is gradually changing, as treatment facilities are being built near cities, fields through which rivers flow into the Baltic Sea are fertilized less with mineral fertilizers, newer and more modern ships sail in the sea, and programs are being created to improve the condition of the Baltic Sea. All this reduces pollution, but good results can be achieved

ECOSYSTEM OF THE BALTIC SEA
The slow water exchange in the Baltic Sea is the reason why this inland sea is particularly sensitive to pollution. pollutants, which are discharged into the sea, remain there for a long time, accumulate in the bottom layer and living organisms. Low water temperature contributes to the slow decomposition of pollutants. The ecosystems of the Baltic Sea cannot be considered fully developed and sustainable. Thus, the Baltic Sea carries a very large anthropogenic load, which is not only necessary but also possible to reduce. Both governmental and intergovernmental bodies, such as Helsinki Commission, as well as non-governmental organizations in different countries. Ecodefense Group is a member Clean Baltic Coalitions, an international public organization created to unite the efforts of environmental NGOs from the countries of the Baltic region. The Helsinki Commission has identified many “hot” spots in the Baltic region, where the impact on environment man manifests itself in especially dangerous forms.

CHEMICAL WEAPONS IN THE BALTIC SEA
According to reports, chemical weapons discovered in West Germany were flooded by the American and British occupying forces in four areas of the coastal waters of Western Europe. In Norwegian deep water near Arendal; in the Skagerrak near the Swedish port of Lyusechil; between the Danish island of Funen and the mainland; near Skagen, the extreme northern point of Denmark. A total of 302,875 tons of poisonous substances, or approximately 1/5 of the total stock of OM, lie on the seabed in six areas of European waters. In addition, at least 120 thousand tons of chemical weapons were sunk in unidentified places in the Atlantic Ocean and in the western part of the English Channel, and at least 25 thousand tons were taken to the USSR. Soviet military archives contain detailed information about what was found in the chemical arsenals of East Germany and sunk in the Baltic Sea. The main threat of the flooded legacy of the Second World War is not that Baltic fishermen periodically raise chemical bombs from the seabed with trawls and cause damage to their health. The famous Russian geneticist Professor V.A. Tarasov conducted a study of this most complex environmental problem and came to depressing conclusions about the negative impact of flooded chemical weapons on the health of many millions of Europeans. He found that what got along the food chain in human body an insignificant amount of toxic substances has not only a strong toxic, but also a mutagenic effect. In particular, in Russia a number of scientists are working on the problem of ensuring reliable isolation of flooded chemical munitions using special composite materials.

The salinity of which is about 20% of the salinity of the oceans, located in the northern part of Europe. Refers to the type of inland seas. Its area is 419 square kilometers. It was the Baltic Sea during the reign of Peter the Great that became the window to Europe.

general characteristics

The average depth of the Baltic Sea is about 50 meters, the largest recorded depth is 470 meters. The deepest sections are located in the region of Scandinavia, the smallest sections are in the area of the Curonian Spit, there is no depth even 5 meters.

More than two hundred rivers flow into the Baltic Sea. The largest of them are Neman, Daugava, Vistula, Neva. Fresh river water is unevenly distributed in it, so the salinity of the Baltic Sea is not the same.

Ice cover in winter is established in the bays from November to April. The thickness of the ice reaches 60 cm. The southern regions of the sea can remain without ice cover all winter. Sometimes floating ice floes are found near the northern shores even in summer period. The last case of complete freezing of the Baltic Sea was recorded in 1987.

In the autumn-winter period, the influx of North Sea salt water increases due to a decrease in water temperature. Because of this, the salinity in the sea increases.

Geographic features

The Baltic Sea is located in the northwest of Europe. In the north, it reaches almost the Arctic Circle itself, the coordinates of the extreme northern point of the sea are 65 degrees 40 minutes s. sh. In the south, it reaches 53 degrees 45 minutes N. sh. From east to west, the Baltic Sea stretches from St. Petersburg (30 degrees 15 minutes E) to the city of Flensburg in Germany (30 degrees 10 minutes E).

The Baltic Sea is surrounded on almost all sides by the coastline, only in the west it has access to the North Sea. The Belomorkanal opens access to the White Sea. Largest part coast belongs to Sweden and Finland (35% and 17%), Russia has about 7%, the rest coastline divided between Germany, Denmark, Poland, Estonia, Lithuania and Latvia.

There are four large bays in the sea - Bothnian, Curonian, Finnish and Riga. The Curonian Lagoon is separated by the Curonian Spit, territorially belongs to Lithuania and Russia (Kaliningrad region). The Gulf of Bothnia is located between Sweden and Finland, it houses the archipelago of the Åland Islands. The Gulf of Finland is located in the east, adjacent to it are the shores of Finland, Estonia and Russia (St. Petersburg).

Baltic Sea: salinity and temperature regime

The temperature of the water surface in the central part is 15-17 degrees. In the Gulf of Bothnia, this figure does not rise above 12 degrees. The highest temperature is observed in the Gulf of Finland.

Due to the weak water exchange and the constant flow of river water in this sea, the salinity is low. In addition, it does not have constant indicators. So, in the area of the Danish coast, the salinity of the water of the Baltic Sea is 20 ppm on the surface. At depth, the indicator can reach up to 30 ppm. The salinity of the surface waters of the Baltic Sea changes the amount in an easterly direction to a smaller side. In the Gulf of Finland, this figure is not more than 3 ppm.

Observations in last years recorded a tendency to increase the percentage of salinity. This figure has increased by 0.5% compared to previous decades. Now the average salinity of the Baltic Sea is 8 ppm. The figure indicates that a liter of sea water contains 8 g of salt. This is the salinity of the Baltic Sea in grams.

Climate of the Baltic Sea

The Baltic has a temperate maritime climate. The average January temperature above the sea surface is 1-3 degrees, in the north and east - 4-8 degrees. Sometimes the invasion of cold currents from the Arctic drops the temperature to -35 degrees for a short time. In winter, the north wind prevails, which causes a cold winter and a long, lingering spring.

IN summer time wind direction changes to west and southwest. On the coast, rainy and cool summer weather is established. Dry hot days in the Baltic are a rarity. The average July temperature here is 14-19 degrees.

The average salinity of the surface waters of the Baltic Sea depends on the season. The period of strong winds falls on the end of autumn and winter. During a storm in November, the waves rise to 6 meters. In winter, ice prevents the formation of high waves. At this time, salinity decreases.

Animal world

The Baltic Sea, whose water salinity varies in different places, is inhabited by quite a variety of species - from purely marine to freshwater inhabitants. So, in the salty waters of the Danish Straits, various mollusks, oysters, crustaceans live. In some places there is even a guest from the North Sea - the mitten crab.

Most commercial fish species choose central waters for habitat, where the average salinity of the surface waters of the Baltic Sea is 7-9 ppm.

In bays with practically fresh water there are pike, bream, crucian carp, roach, ide, burbot, eel. On an industrial scale, Baltic herring, cod, sprat, salmon and sea trout are caught here.

Spa vacation

Due to the cool climate, the resorts of the Amber Region are not to everyone's taste. They have little in common with the hot beaches of Turkey, Egypt, Crimea. Officially, the beach season in the Baltic lasts from June to the end of September, while in June the water does not always warm up to even 20 degrees.

However, not everyone likes hot crowded beaches. Many people prefer to combine a beach holiday with an active one, for example, with the study of culture and sights. The beaches of the Baltic Sea are very a good option. You can choose the resort of Palanga, Jurmala, Gdansk, Sopot, Svetlogorsk and others. The ideal time to relax here is July and the first half of August, when the water temperature warms up to 25 degrees. Temperatures of 25-27 degrees were recorded in the shallow waters of the Gulf of Riga.

Environmental problems of the Baltic Sea

In recent years, there has been a significant deterioration in water quality due to pollution. One of the reasons is that the rivers flowing into the sea carry already polluted waters. And since the sea is inland and has the only exit through the Danish straits, there is no possibility of natural self-purification.

The following main water pollutants can be distinguished:

industrial, agricultural and municipal waste that comes from urban sewers, often discharged directly into the sea;
heavy metals - come from city drains, some fall out with precipitation;
spilled oil products - in the era of the development of shipping, the leakage of oil products is not uncommon.

The consequences of pollution are the formation of a film on the surface of the water and the termination of oxygen access to its inhabitants.

The main sources of water pollution:

active shipping;
accidents at industrial enterprises and power plants;
industrial and household drains;
polluted rivers flowing into the sea.

Helsinki Convention

In 1992, nine states of the Baltic basin signed a convention on the observance of environmental and maritime rights. The main body is the commission headquartered in Helsinki. The main goal of the commission is the development and implementation of measures aimed at protecting the environment marine environment, conducting research, promoting the safe navigation of ships.

At the head of the commission for a period of two years are alternately states with access to the sea. From 2008 to 2010, Russia held the chairmanship.

Drunken forest and amber

In the Kaliningrad region on the Curonian Spit there is an unusual place, popularly referred to as the Dancing or Drunken Forest. On a small area (within 1 square km), pine trees planted under the USSR grow. The bottom line is that the trees are strangely curved, and some are even twisted into a loop. Scientists cannot accurately explain this phenomenon. Versions are different: the climatic factor, genetics, attack pests and even the influence of space. There are rumors that there are no sounds in the forest and mobile communications are lost. The mystery of the forest annually attracts domestic and foreign tourists.

In autumn, when a storm begins, along with the sand, the sea throws amber ashore. Mainly on the coast of Poland, Russia, Germany. This period is awaited by local craftsmen and visiting adventurers. There is a belief that amber is a wish fulfillment stone. Amber souvenirs fill the atmosphere of the house with positive energy, promote harmony in personal relationships.

This is how the Baltic Sea is, the salinity, climate and richness of which attract with its uniqueness.

Baltic "Titanic"

In 1994, on the night of September 28, a disaster occurred at sea, the mystery of which remains a mystery to this day. On the evening of September 27, the ferry "Estonia" left Tallinn for its last voyage. There were about 1,000 passengers and crew on board. The ship has been making a regular voyage to Stockholm for a long time. The route is familiar, no unforeseen situations were expected on the route. The sea was stormy, but neither the passengers nor the crew members were bothered by this. The usual Baltic autumn, it was believed that a storm was not terrible for a ship of this type.

Closer to midnight, the storm intensified, but the passengers were calm and prepared for bed. By that time, the ferry had departed from the port for 350 km. At this time, the ferry met with the oncoming ship "Mariella". After one in the morning, a distress signal was received from the ferry, after which the ship disappeared from the radar. "Mariella" and the ships nearby hurried to the place of the tragedy. By 3:00 am, rescue helicopters arrived at the crash site. Many victims no longer needed help - death came from hypothermia. In total, about 200 passengers were rescued, another 95 were identified and officially declared dead.

The Baltic Sea and its coastline is an interesting place, saturated with memories of the Vikings, pacifying with its northern landscapes. It differs from other seas in the nature of the relief, temperature and features of the coastline. The Baltic is of great historical and geopolitical importance for Russia.

Geographical position

The Baltic Sea on the map is located in the north of Europe and belongs to 54°46′ and 65°56′ north latitude and 9°57′ and 30°00′ east longitudes. The extreme points that the Baltic Sea has on the map: near the Arctic Circle in the north, near Wismar in the south, the eastern one is near St. Petersburg and the western extreme point located in the Flensburg area.

Relief and depths

The bottom relief has slight differences from the outlines of the shores that limit the Baltic Sea. Depths, in turn, also depend on the nature of the surrounding area. The southern side of the sea, belonging to Germany, Poland and Denmark, is gently sloping, flat, with sandy beaches. The rocky shore and uneven rocky bottom are located in the northern part. The depth and relief of the Baltic Sea are different in different areas. The bottom has a very complex dissected surface. There are depressions that delimit the uplands and bases of the islands that the Baltic Sea includes.

Depths elsewhere are shallow. For example, there are areas of pronounced accumulative relief - these are the shallow Gulfs of Finland, Riga and Bothnia.

Thus, the depth of the Baltic Sea is less than 200 meters. The Landsortskaya depression is different. The maximum depth of the Baltic Sea is located in this area and is about 470 meters. The Landsort Basin extends in a southwestern direction. The rest are of lesser depth: Gotlandskaya - 249 m and Gdanskaya - 116 m in the central part of the sea, Arkonskaya - 53 m and Bornholmskaya - 105 m (in the western part).

Sea bays and straits

Refers to inland seas. In the southwest, it adjoins the North Sea through the Danish straits (Small and Great Belt, Sound), Skagerrak and Kattegat.

In the east it is located between Estonia and Latvia. The Estonian island of Saaremaa partially separates the bay from the rest of the sea. There are also large Gulfs of Finland and Bothnia

The Neva Bay is the eastern section of the Gulf of Finland. At a distance of about 50 km from St. Petersburg is located on which the city of Kronstadt was built. The dam connects the island city and St. Petersburg, the highway is laid along the dam, so that people have the opportunity to get to the mainland and back by car.

In the northeastern part, where the border between Russia and Finland passes, the Gulf of Finland is connected to the Vyborg Gulf. The Saimaa Canal, leased by Finland, also originates there. It performs the function of a transport route, and is also popular with tourists in warm weather. Guests come here for the beauty of landscapes, and for duty-free shopping.

Coast

The coast of the Baltic Sea is diverse. Latvia has an accumulation-type coast formed as a result of the accumulation of sand on the coasts. The lagoon coast, formed by a bay and separated from the sea by a narrow spit, is located near Kaliningrad. Leveled shores border most of the sea, in particular, belong to Poland. And they are formed under the influence of prevailing winds and coastal currents. Fjords are narrow and deep sea bays with towering steep and rocky shores that surround the sea from the north. They were formed by flooding of tectonic faults and river valleys. The skerry shore appeared as a result of flooding of territories with smoothed glaciers composed of crystalline rocks. These hills protrude above the sea surface in the form of many skerries with traces of glacial activity.

The following countries have access to the Baltic Sea - Russia, Latvia, Estonia, Lithuania, Germany, Poland, Sweden, Denmark, Finland. After the collapse of the USSR, Russia was left with a small segment of the coast, only 7%, instead of the former 25%, which brings annual losses to the state. Therefore, one port was laid in Primorsk near Vyborg, which will specialize in coal and dry cargo. And the second port is located in the Luga Bay, it will be oil loading.

Tectonic processes

To this day, the Baltic Sea continues to change. It has shallow depths compared to other parts of the Atlantic Ocean. Actually, this vast reservoir during its existence several times became a lake and again a sea due to tectonic processes.

Currently, the next stage of separating the sea from the ocean and turning it into a fresh lake is underway. It is characterized by the rise of the bottom of the Gulf of Bothnia by several centimeters per year and the flooding of the southern coasts. Such processes create a need for northern ports to lengthen their piers. To save the low parts of the coast, embankments are being made.

Temperature layers

The temperature of the Baltic Sea, in turn, depends on the depth. The predominant part of the waters of a huge reservoir can be divided into surface, transitional and deep water masses.

The surface layer is from 0 to 20 meters, in some places - from 0 to 90 meters with a temperature of 0 to 20 degrees. It is formed as a result of the interaction of the sea with the atmosphere and waters flowing from the mainland. The temperature of the Baltic Sea in this layer varies with the seasons. In summer, cold intermediate water masses are more pronounced, formed in connection with a significant warming of the sea surface.

The deep layer (bottom and 50-60 meters above it) has a temperature of 1 to 15 degrees. This layer is formed by the flow of water through the straits of the Small and Great Belt and their mixing.

The transition layer includes water at a depth of 20-60 to 90-100 meters. They have a temperature of 2-6 degrees, are formed by mixing the waters of the deep and surface layers.

Features of water temperature in the Baltic Sea

Separate areas of the sea are distinguished by the peculiarities of the structure of the waters. So, Bornholmsky district has a warm layer (7-11 degrees) both in summer and in winter. It is formed by warm waters coming here from the more heated Arkona basin. In it, due to the shallow depth of the sea and the movement of waters in the horizontal plane, there is no cold intermediate layer in summer.

Seasonal change in temperature

In winter, in the open sea, the water temperature is higher than near the coast, while it differs from the western and eastern coasts. In February, the temperature is 0.7 degrees near Ventspils, in the open sea of the same latitude - approximately 2 degrees, near the western coast - 1 degree.

In summer surface water V different parts The seas also differ in temperature. The prevailing westerly winds drive surface water masses away from the western shores. The underlying cold waters rise to the surface. As a result of this phenomenon, in the southern and central regions, as well as near the western coasts, the temperature drops. In addition, a cold current from the Gulf of Bothnia flows south along the coast of Sweden.

Seasonal fluctuations in water temperature are pronounced only in the upper 50-60 meters, deeper indicators change slightly. There are no temperature changes in cold weather, but with increasing depth, the indicators slightly decrease. In warm weather, the water temperature rises to horizons of 20-30 meters due to mixing. Even in summer, when the surface layer of water is warm and the thermocline is more pronounced than in spring, a cold intermediate layer is preserved.

The depth, relief and other features of the Baltic Sea depend on many factors. This is a geographical position, being in the northern latitudes, as well as being located on the continental plate.

BALTIC SEA(Late Latin Mare Balticum, among the ancient Slavs - the Varangian Sea or the Svean Sea), the inland sea of the Atlantic Ocean, between the Scandinavian Peninsula and the mainland shores of North-Western Europe. Washes the shores of Sweden, Finland, Russia, Estonia, Latvia, Lithuania, Poland, Germany, Denmark. Joins the North Sea in the southwest Danish Straits. The maritime boundary of the Baltic sea runs along the southern entrances of the Øresund, Great Belt, and Lesser Belt straits. The area is 419 thousand km 2, the volume is 21.5 thousand km 3. The greatest depth is 470 m. Depths above the thresholds of the Danish Straits: Darser - 18 m, Drogden - 7 m. The cross section above the thresholds is 0.225 and 0.08 km 2, respectively, which limits water exchange with the North Sea. The B. m. protrudes deeply into the Eurasian continent. The heavily indented coastline forms numerous bays and coves. The largest bays: Gulf of Bothnia, Gulf of Finland, Gulf of Riga, Curonian Lagoon, Szczecin Bay, Gdansk Bay. The shores of the B. m. in the north are high, rocky, mostly of the skerry and fjord types, in the south and southeast they are mostly low-lying, of the lagoon type, with sandy and pebble beaches. The largest islands: Gotland, Bornholm, Saaremaa, Muhu, Hiiumaa, Eland and Rügen. There are many small rocky islands - skerries, located along the northern shores (there are over 6 thousand in the Aland Islands group).

Relief and geological structure of the bottom

The Baltic Sea is shallow, lies completely within the shelf, depths up to 200 m occupy 99.8% of its area. The most shallow are the Gulfs of Finland, Bothnia and Riga. Their bottom sections have a leveled accumulative relief and a well-developed cover of loose sediments. Most of the bottom of the Baltic Sea is characterized by a strongly dissected relief. The bottom of its basin has depressions delimited by elevations and island bases: in the west - Bornholmskaya (105 m) and Arkonskaya (53 m), in the center - Gotlandskaya (249 m) and Gdanskaya (116 m); to the north of the island of Gotland, from the northeast to the southwest, the deepest depression, Landsortskaya (up to 470 m), stretches. Numerous stone ridges, ledges are traced in the central part of the sea - continuations of glints stretching from the northern coast of Estonia to the northern tip of the island of Öland, underwater valleys, glacial-accumulative landforms flooded by the sea.

B. m. occupies a depression in the west of the ancient East European Platform. The northern part of the sea is located on the southern slope Baltic Shield; the central and southern parts belong to a large negative structure of the ancient platform - the Baltic syneclise. The extreme southwestern part of the sea enters the limits of the young Western European platform. The bottom in the north of the Baltic sea is composed mainly of complexes of Precambrian age, overlain by a discontinuous cover of glacial and modern marine deposits. Silurian and Devonian sediments take part in the bottom structure in the central part of the sea. The ledges traced here are formed by the Cambrian-Ordovician and Silurian rocks. The Paleozoic complexes in the south are overlain by a thick layer of glacial and marine sediments.

During the last ice epoch (late Pleistocene), the depression of the B. m. was completely covered by an ice sheet, after the melting of which the Baltic Glacial Lake was formed. Late Late Pleistocene, ca. 13 thousand years ago, there was a connection of the lake with the ocean and the depression was filled with sea water. Communication with the ocean was interrupted in the interval of 9–7.5 thousand years ago, after which a marine transgression followed, the deposits of which are known on the modern coast of the Baltic Sea. In the northern part of the Baltic Sea, uplift continues, the rate of which reaches 1 cm per year.

Bottom sediments at depths of more than 80 m are represented by clayey silts, under which lies banded clay on glacial deposits; at shallower depths, silt is mixed with sand; sands are common in coastal areas. There are boulders of glacial origin.

Climate

B. m. is characterized by a temperate maritime climate with features of continentality. Its seasonal features are determined by the interaction of baric centers: the Icelandic Low and the Azores High in the west and the Siberian High in the east. Cyclonic activity reaches its greatest intensity in the autumn-winter months, when cyclones bring cloudy, rainy weather with strong western and southwestern winds. The average air temperature in February is from -1.1 °C in the south, -3 °C in the central part of the sea to -8 °C in the north and east, and up to -10 °C in the northern part of the Gulf of Bothnia. Rarely and for a short time, the cold arctic air penetrating the Baltic Sea lowers the temperature to -35 °C. In summer, westerly winds also blow, but of low strength, bringing cool, humid weather from the Atlantic. The air temperature in July is 14–15 °C in the Gulf of Bothnia and 16–18 °C in the rest of the sea. Rare inflows of warm Mediterranean air cause short-term temperature rises up to 22–24 °C. Annual precipitation varies from 400 mm in the north to 800 mm in the south. The greatest number of days with fogs (up to 59 days a year) is noted in the south and in the central part of the Baltic Sea, the smallest (22 days a year) - in the north of the Gulf of Bothnia.

Hydrological regime

The hydrological conditions of the Baltic sea are determined by its climate, a significant influx of fresh water, and limited water exchange with the North Sea. Approx. flows into B. m. 250 rec. River flow averages 472 km 3 per year. Most major rivers: Neva - 83.5 km 3, Vistula - 30, Neman - 21, Western Dvina - 20 km 3 per year. Freshwater runoff is unevenly distributed throughout the territory. 181 km3 per year enters the Gulf of Bothnia, 110 km3 enters the Gulf of Finland, 37 km3 enters the Gulf of Riga, and 112 km3 per year into the central part of the Baltic Sea. The amount of fresh water precipitation (172 km 3 per year) is equal to evaporation. Water exchange with the North Sea averages 1660 km 3 per year. Fresher waters with a surface runoff flow out of the Baltic Sea into the North Sea, while salty North Sea water with a near-bottom current enters through the straits from the North Sea. Strong westerly winds usually increase the inflow, while easterly winds increase the outflow of water from the Baltic Sea through the Danish Straits.

The hydrological structure of the B. m. in most areas is represented by surface and deep water masses, separated by a thin intermediate layer. The surface water mass occupies a layer from 20 to (in some places) 90 m, its temperature during the year varies from 0 to 20 °C, salinity is usually in the range of 7–8‰. This water mass is formed in the sea itself as a result of the interaction sea waters with fresh water precipitation and river runoff. It has winter and summer modifications, which differ mainly in temperature. In the warm season, the presence of a cold intermediate layer is noted, which is associated with the summer heating of water on the surface. The deep water mass occupies a layer from 50–100 m to the bottom, its temperature varies from 1 to 15 °C, salinity - from 10.0 to 18.5‰. Deep water is formed in the bottom layer as a result of mixing with high salinity water coming from the North Sea. The renewal and ventilation of bottom waters are highly dependent on the inflow of North Sea water, which is subject to interannual variability. With a reduction in the influx of salt water into the sea, at great depths and in depressions in the bottom topography, conditions are created for the appearance of dead water phenomena. Seasonal changes in water temperature capture the layer from the surface to 50–60 m and usually do not penetrate deeper.

Wind waves develop especially strongly in the autumn-winter period with prolonged and strong southwestern winds, when waves 5–6 m high and 50–70 m long are observed. The highest waves are observed in November. In winter, sea ice prevents the development of waves.

Cyclonic (counterclockwise) circulation of water, complicated by eddy formations of different scales, is everywhere traced in the Baltic Sea. The velocities of constant currents are usually approx. 3–4 cm/s, but in some areas sometimes increase to 10–15 cm/s. Due to the low velocities of the current, they are unstable, their pattern is often disturbed by the action of winds. Storm winds cause strong wind currents with speeds of up to 150 cm/s, which quickly fade after a storm.

Because of their insignificant connection with the ocean, the tides in the sea are weakly expressed, and the height is 0.1–0.2 m. Surge-induced level fluctuations reach significant values (up to 2 m at the tops of the bays). Combined action of wind and sharp drops atmospheric pressure causes seiche level fluctuations with a period of 24–26 hours. The magnitude of such fluctuations is from 0.3 m in the open sea to 1.5 m in the Gulf of Finland. Seiche waves with surge western winds sometimes cause a rise in the level at the top of the Gulf of Finland to 3-4 m, which delays the flow of the Neva and leads to floods in St. Petersburg, sometimes catastrophic: in November 1824 about 410 cm, in September 1924 - 369 cm .

The temperature of the water on the surface of the B. m. varies greatly from season to season. In August, in the Gulf of Finland, the water warms up to 15-17 ° C, in the Gulf of Bothnia - 9–13 °C, in the central part of the sea– 14–18 °C, in the southern regions it reaches 20 °C. In February, in the open part of the sea, the water temperature on the surface is 1–3 °C, in bays and bays below 0 °C. The salinity of water on the surface is 11‰ at the outlet of the Danish Straits, 6–8‰ in the central part of the sea, and 2‰ or less at the tops of the Gulf of Bothnia and the Gulf of Finland.

B. m. refers to the so-called. brackish basins, in which the temperature of the highest density is above the freezing point, which leads to an intensification of the formation process sea ice. Ice formation begins in November in the bays and off the coast, later in the open sea. In severe winters, the ice cover occupies the entire northern part of the sea and the coastal waters of its central and southern parts. The thickness of landfast (fixed) ice reaches 1 m, drifting - from 0.4 to 0.6 m. Ice melting begins at the end of March, spreads from southwest to northeast and ends in June.

Research History

The first information about B.'s studies of m. is associated with the Normans. All R. 7th c. they penetrated the Gulf of Bothnia, discovered the Aland Islands, in the 2nd floor. 7th–8th centuries reached the western coast of the Baltic, discovered the Moonsund archipelago, first penetrated the Gulf of Riga, in the 9th-10th centuries. used the coast from the mouth of the Neva to the Gdansk Bay for trade and piracy. Hydrographic and cartographic work was carried out by Russians in the Gulf of Finland at the beginning of the 18th century. In 1738, F. I. Soymonov published an atlas of B. m., compiled from domestic and foreign sources. All R. 18th century Long-term studies were carried out by A. I. Nagaev, who compiled a detailed navigation chart of the B. m. The first deep-sea hydrological studies in the middle. 1880s were performed by S. O. Makarov. Since 1920, hydrological work has been carried out by the Hydrographic Department of the Navy, the State Hydrological Institute (Leningrad), and from the 2nd half. 20th century extensive comprehensive research was launched under the leadership of the Leningrad (St. Petersburg) Department of the State Oceanographic Institute of the Russian Academy of Sciences.

Economic use

Fish resources consist of freshwater species living in the fresh waters of the bays (crucian carp, bream, pike, pike perch, chub), the Baltic salmon herd and purely marine species distributed mainly in the central part of the sea (cod, herring, smelt, vendace, sprat). Baltic herring, sprat, herring, smelt, river flounder, cod, perch, and others are fished. Eel is a unique object of fishing. Placers of amber are common on the coast of the Baltic Sea, and mining is carried out near Kaliningrad (Russia). Oil reserves have been discovered at the bottom of the sea, and industrial development has begun. Iron ore is mined off the coast of Finland. B.'s value of m as a transport artery is great. Large volumes of transportation of liquid, bulk, and general cargoes are carried out along the B. m. A significant part of the foreign trade of Denmark, Germany, Poland, Russia, Lithuania, Latvia, Estonia, Finland, and Sweden is carried out through the Baltic Sea. The cargo turnover is dominated by oil products (from the ports of Russia and from the Atlantic Ocean), coal (from Poland, Russia), timber (from Finland, Sweden, Russia), pulp and paper (from Sweden and Finland), iron ore(from Sweden); An important role is also played by machinery and equipment, the major producers and consumers of which are the countries located on the shores and in the basin of the Baltic Sea.

On the bottom of the B. m. between Russia and Germany, a gas pipeline was laid (two threads, each with a diameter of 1220 mm) “Nord Stream” (“Nord Stream”). Passes from Portovaya Bay near Vyborg ( Leningrad region) to Lubmin near Greifswald (Germany, the federal state of Mecklenburg - Vorpommern); length 1224 km (the longest underwater gas pipeline in the world). The capacity (capacity) of the gas pipeline is 55 billion m³ of gas per year. The maximum depth of the sea in the places where the pipe passes is 210 m. 148 sea vessels were involved in the construction. The total mass of steel used in the construction of the gas pipeline is 2.42 million tons.

At the preparatory stage, Nord Stream spent approx. 100 million euros. In 1997, preparatory work began on the construction of the offshore section: Scientific research, on the basis of which an approximate route of the gas pipeline is determined. In 2000, by decision of the Commission of the European Union on Energy and Transport, the project was awarded the status of TEN (“Trans-European Networks”). The construction of the gas pipeline began on April 9, 2010. The first string of the gas pipeline was put into operation on November 8, 2011, the second - on October 8, 2012.

In September 2015, a Shareholders' Agreement was signed for the implementation of the project, called Nord Stream 2. On July 8, 2016, Nord Stream 2 completed a tender to select a contractor for applying concrete weight coating to gas pipeline pipes.

344 ships with a total carrying capacity of 1,196,600 deadweight tons are registered in the ports of the Baltic sea. The largest ports: St. Petersburg, Kaliningrad, Vyborg, Baltiysk (all - Russia); Tallinn (Estonia); Riga, Liepaja, Ventspils (all - Latvia); Klaipeda (Lithuania); Gdansk, Gdynia, Szczecin (all - Poland); Rostock - Warnemünde, Luebeck, Kiel (all - Germany); Copenhagen (Denmark); Malmö, Stockholm, Lulea (all - Sweden); Turku, Helsinki and Kotka (all from Finland). Maritime passenger and ferry traffic is developed: Copenhagen - Malmo, Trelleborg - Sassnitz (railway ferries), Nortelje - Turku (car ferry), etc. Crossings across the straits: Great Belt (1998; length 6790 m), Small Belt (both - Denmark; 1970; 1700 m), Øresund (Denmark - Sweden; 2000; 16 km); it is planned to build a crossing across the Femer Strait (Denmark - Germany; 2018; 19 km). Due to shallow depths, many places are inaccessible to ships with a significant draft, but the largest cruise ships pass through the Danish Straits into the Atlantic Ocean.

There are many resort places on the southern and southeastern coasts: Sestroretsk, Zelenogorsk, Svetlogorsk, Pionersky, Zelenogradsk, Curonian Spit (all - Russia); Pärnu, Narva-Jõesuu (both - Estonia); Jurmala, Saulkrasti (both - Latvia); Palanga, Neringa (both - Lithuania); Sopot, Hel, Kolobrzeg, Koszalin (all - Poland); Ahlbeck, Binz, Heiligendamm, Timmendorf (all from Germany); Öland island (Sweden).

Ecological state

The marine sea, which has a difficult water exchange with the World Ocean (renewal of water lasts about 30 years), is surrounded by industrialized countries and experiences an extremely intense anthropogenic load. Main ecological problems associated with the disposal of chemical weapons at the bottom of the sea, the discharge of sewage from large cities into the sea, the washing off of chemical fertilizers used in agriculture, and especially with shipping - one of the most intensive in the world (mainly oil tankers). After the entry into force of the Convention for the Protection of the Marine Environment of marine marine life in 1980, the ecological situation improved due to the commissioning of a large number of sewage treatment plants, a reduction in the use of chemical fertilizers, and control over technical condition courts. The concentration of toxic substances such as DDT and polychlorinated biphenyls, petroleum hydrocarbons has decreased. The content of dioxins in the Baltic herring is 3 times lower than the MPC, the gray seal population has recovered. Consideration is being given to giving the BM the status of a particularly vulnerable sea area.

The Baltic Sea, like a real European one, washes the borders of several states at once. If earlier many principalities and empires fought for the right to own the ports located on it, today the situation in the region of the water area is calm. Nine states have access to the shores of the Baltic Sea: Russia, Estonia, Lithuania, Latvia, Poland, Denmark, Sweden, Germany and Finland.

The Baltic Sea can be called a typical inland sea. It is located in the northwestern part of Eurasia and is connected to the Atlantic Ocean in the North Sea through the Danish straits. The size of the water area is quite large for Europe - 419,000 sq.m, despite the fact that the average depth is 51 m (the maximum figure is 470 m). The Baltic Sea is full-flowing due to the large number of rivers that flow into it - these are the world-famous Vistula, Neman, Neva and Daugava. The largest among them (bringing large quantity water in the pool) is our Neva.

As for the shores of the Baltic Sea, relative to the mainland of the planet, they stretched from the southwest to the northeast. The widest place on land is called a piece of land from St. Petersburg to Stockholm - this is almost 650 km of continuous beach.

It will be fair to note that the Baltic was far from always under the sphere of influence of Russia. These northern shores have long attracted the kings and princes of the specific feudal states. Quite often, commanders, together with armies, tried to get a tidbit of the seashore, but they could not get what they wanted. One has only to recall the bloody attempts of Tsar Ivan the Terrible and the disastrous Livonian War he started.

Luck smiled at Russia only at the beginning of the 18th century. The Northern War, which engulfed almost the entire northern and eastern parts of Europe, allowed Peter the Great to get his piece of the Gulf of Finland and begin the process of "Europeanization" of the Russian people.

Cities on the Baltic Sea in Russia

Today, the Baltic Sea is considered not only a strategic area, but also an excellent resort for residents of the country and neighboring regions. The water here is quite cold, sometimes capricious and violent, which, however, does not deter tourists who come here every summer.

Kaliningrad

(Port terminal Kaliningrad, located in the Kaliningrad Bay)

The central city of the region, as is known, was previously called Keninsberg. Today it is a large city on the sea, which has managed to retain the outlines of German prosperity, while acquiring a typical Russian look. Today people come here not only to the grave of the great Kant, but also to medical mineral water and sandy beaches.

Svetlogorsk and Zelenogradsk

Two typical resort towns that differ only in size. The first is larger and more touristy. A large number of hotels and restaurants for every taste, the locals have long adapted to the needs of guests and offer a quiet and cozy holiday on the seashore.

In addition, the region has a huge number of small villages in the coastal zone. Many of them trade with amber mining and offer excursions to old breweries. Today, the Russian shores of the Baltic Sea have become completely Russified, and only the pointed roofs of temples and two-story houses with red tiles stretching along the coast remind of the time when the lands belonged to Europe.