The seas are like large natural complexes.

Goals and objectives of the lesson:

To form ideas about the nature of the White and Azov Seas. Show the relationships between the components of the sea. Expand knowledge about natural complexes.

Equipment:

Physical map of Russia, map of the oceans, table of the sea of ​​Russia, movie of the sea of ​​Russia.

During the classes.

1. Organizing time.

2. Repetition. Checking homework.

Remember what a natural complex is, and what components of land it consists of.

Why are natural complexes diverse?

Name the components of any natural complex.( Relief, rocks, soil, plants, animals, climate, water).

Who founded the science that studies PTK? ( ).

What is it called? (Landscape science).

3. Learning new material.

Natural complexes exist not only on land, but also in the ocean. The seas are natural complexes consisting of bottom rocks, water, flora and fauna. Man has been using the resources of the seas for a long time. The significance of the interconnections between the components of the sea will help to rationally use its resources.

Today we will get acquainted with the complexes of the White and Azov Seas. Find them on the map.

In the Sea of ​​Azov, find the Kerch Strait, the Sivash Bay, the rivers flowing into the Sea of ​​Azov: Don, Kuban.

In the White Sea - the Strait of the Throat of the White Sea, Cape Svyatoy Nos, Cape Kanin Nos, Kandalashsky Bay, lips - Onega, Mezenskaya, Dvinskaya; Find the rivers flowing into the White Sea: Northern Dvina, Mezen, Onega. The mouths of these rivers are flooded with water of the White Sea, have a funnel shape, they are called estuaries.

About the seas - internal, connected with the oceans by narrow straits, therefore they have a special appearance, they are special complexes. Let's get to know each other in more detail with the White Sea.

1gr. To characterize the natural complex of the White Sea according to the plan:

4) Temperature (freezes?)

5) Salinity of water.

8) Rivers flowing into the sea.

9) Biological resources.

10) Problems of the sea.

Acquaintance with the PTC of the White Sea

WHITE SEA, inland sea Arctic Ocean, off the northern coast of the European part of the Russian Federation. 90 thousand km2. Large islands: Solovetsky, Morzhovets, Mudyugsky. In winter it is covered with ice. Tides up to 10 m (in the Mezen Bay).

The White Sea in the north is connected by the Gorlo Strait of the White Sea with the Barents Sea. The sea has low-lying, but strongly indented shores; this is the Kandalaksha Bay and lips (they are called estuaries). Onega, Dvinskaya, Mezenskaya. The White Sea is small in size. The bottom relief is uneven. The sea is not deep. The average depth is 67 m. the maximum depth is 350 m. It is located on the continental shelf. The salinity of the White Sea is less than that of the Barents Sea, in the bays 10-14%o. In the north, salinity is higher (30%o) than in the south - 20-26%o. because in the south, the rivers Onega, S. Dvina, Mezen flow into the sea, which freshen the water of the White Sea, especially in the bays. The biological resources of the White Sea are poorer than those of the Barents Sea. The White Sea is colder than the Barents Sea, into which a warm current enters, the White Sea freezes. Of the fish, herring, salmon, brown trout, cod and others live here. Ports: Arkhangelsk, Onega, Belomorsk, Kandalaksha, Kem, Mezen. It is connected with the Baltic Cape of the White Sea-Baltic Canal, with the Azov, Caspian and Black Seas by the Volga-Baltic Waterway.

In the White Sea is the Kandalaksha Nature Reserve, where eider nesting sites are protected. This bird lines its nests with its fluff, which has the ability to retain heat. The fluff is light. People collect eider down.

Acquaintance with the PTC of the Sea of ​​Azov

2gr. To characterize the natural complex of the Sea of ​​\u200b\u200bAzov according to the plan:

1) Which ocean basin does the sea belong to?

2) Internal or marginal (connection with the ocean).

3) Area compared to other seas,

4) Temperature (freezes?)

5) Salinity of water.

6) Depths prevailing and greatest (conclusion - deep, shallow).

7) Influence of depth on other components (salinity, temperature, organic world).

8) Rivers flowing into the sea.

9) Biological resources.

10) Problems of the sea.

SEA OF AZOV(other Russian - Surozh Sea), in the south of the East European Plain. Kerch Prospekt. connected to the Black Sea. 39 t. km2 Belongs to the Atlantic Ocean basin, inland. It is shallow, the depth is 5-7 m. In some places up to 15 m. Large bays: Taganrog, Sivash. Large rivers fall into Don and Kuban. Freezes for 2-3 months. From the end of December to the end of February - the beginning of March. The waters of the rivers significantly desalinate the sea water at their confluence - up to 5-6‰ with an average salinity of 11-13‰. The temperature of sea water in summer is +25.30˚С, in winter it is below 0˚. Fishing (anchovy, sprat, bream, pike perch). Main ports: Mariupol, Taganrog, Yeysk, Berdyansk. Resorts. As a result of anthropogenic impacts, the ecological situation has deteriorated; a search is underway for scientifically based ways of restoring the natural complexes of the Azov m.

To consolidate and create an image of the sea, show the presentation "White and Azov Seas" during the test of independent work.

Summing up the lesson.

Rating with comments

Located on the northern outskirts of the European part of our country, the White Sea occupies the space between 68°40? and 63°48? With. sh., and 32°00? and 44°30? in. and is entirely located on the territory of Russia. By its nature, it belongs to the seas of the Arctic Ocean, but this is the only one of the Arctic seas that lies almost entirely south of the Arctic Circle, only the northernmost regions of the sea go beyond this circle. Bizarre in shape, the White Sea is deeply incised into the continent, almost everywhere it has natural land boundaries, and only from the Barents Sea it is separated by a conditional border - the line Cape Svyatoy Nos - Cape Kanin Nos. The White Sea, surrounded by land on almost all sides, belongs to the inland seas. In size, this is one of our smallest seas. Its area is 90 thousand km2, the volume is 6 thousand km3, the average depth is 67 m, the maximum depth is 350 m. The modern shores of the White Sea, different in external forms and landscapes, have their own geographical names and belong to different geomorphological types of the Neroven coasts and the bottom topography is complex seas. The deepest areas of the sea are the Basin and the Kandalaksha Bay, in the outer part of which the maximum depth is noted. The depths gradually decrease from the mouth to the top of the Dvina Bay. The bottom of the shallow Onega Bay is slightly elevated above the Basin. The bottom of the Throat of the Sea is an underwater trench about 50 m deep, stretched along the strait somewhat closer to the Tersky coast. The northern part of the sea is the most shallow. Its depths do not exceed 50 m. The bottom here is very uneven, especially near the Kaninsky coast and the entrance to the Mezen Bay. This area is dotted with many cans, which are distributed in several ridges and are known by the name "Northern Cats". The shallow water of the northern part and the Gorlo, compared to the Basin, hinders its water exchange with the Barents Sea, which affects the hydrological conditions of the White Sea. The position of this sea in the north of the temperate zone and partly beyond the Arctic Circle, belonging to the Arctic Ocean, the proximity of the Atlantic Ocean and the almost continuous ring of land surrounding it determine both maritime and continental features in the climate of the sea, which makes the climate of the White Sea transitional from oceanic to mainland. The influence of the ocean and land to a greater or lesser extent manifests itself in all seasons. Winter on the White Sea is long and severe. At this time, an extensive anticyclone is established over the northern part of the European territory of the Union, and intensive cyclonic activity is developed over the Barents Sea. In this regard, predominantly southwestern winds blow in the White Sea at a speed of 4–8 m/s. They bring with them cold cloudy weather with snowfall. In February, the average monthly air temperature over almost the entire sea is 14-15°, and only in the northern part does it rise to 9°, since here the warming influence of the Atlantic Ocean is felt. With significant intrusions of relatively warm air from the Atlantic, southwestern winds are observed and the air temperature rises to 6--7 °. The displacement of an anticyclone from the Arctic into the White Sea region causes northeasterly winds, clearing and cooling down to 24--26 °, and sometimes very severe frosts. Summers are cool and moderately humid. At this time, an anticyclone usually sets up over the Barents Sea, and intense cyclonic activity develops to the south and southeast of the White Sea. With such a synoptic situation, northeast winds with a force of 2-3 points prevail over the sea. The sky is overcast with frequent heavy rains. The air temperature in July is on average 8--10 °. Cyclones passing over the Barents Sea change the direction of the wind over the White Sea to the west and southwest and cause an increase in air temperature to 12--13°. When an anticyclone sets up over northeastern Europe, southeasterly winds and clear sunny weather prevail over the sea. The air temperature rises on average to 17-19°, and in some cases in the southern part of the sea it can reach 30°. However, cloudy and cool weather still prevails in summer. Thus, there is no long-term stable weather in the White Sea for almost the entire year, and the seasonal change in the prevailing winds is monsoonal in nature. These are important climatic features that significantly affect the hydrological conditions of the sea. Hydrological characteristic. The White Sea is one of the cold Arctic seas, which is associated not only with its position in high latitudes, but also with the hydrological processes occurring in it. The distribution of water temperature on the surface and in the sea column is characterized by great diversity from place to place and significant seasonal variability. In winter, the water temperature on the surface is equal to the freezing temperature and is on the order of 0.5--0.7 ° in the bays, up to 1.3 ° in the Basin and up to -1.9 ° in the Gorla and the northern part of the sea. These differences are explained by unequal salinity in different areas of the sea. In the spring, after the sea is freed from ice, the surface of the water rapidly warms up. In summer, the surface of relatively shallow bays is best heated. The water temperature on the surface of the Kandalaksha Bay in August is on average 14-15°, in the Basin 12-13°. The lowest temperature on the surface is observed in Voronka and Gorla, where strong mixing cools the surface waters to 7-8°. In autumn, the sea cools rapidly and spatial differences in temperature are smoothed out. The change in water temperature with depth occurs differently from season to season in different areas of the sea. In winter, the temperature, close to the surface, covers a layer of 30-45 m, followed by a slight increase to a horizon of 75-100 m. This is a warm intermediate layer - the remnant of summer warming. Below its temperature decreases, and from the horizons of 130-140 m to the bottom it becomes equal to 1.4 °. In spring, the surface of the sea begins to warm up. Heating extends up to 20 m. From here, the temperature drops sharply to negative values ​​at a horizon of 50–60 m. In summer, the thickness of the heated layer increases to 30–40 m. The temperature in it differs little from the surface. From these horizons, at the beginning, an abrupt, and then a more gradual decrease in temperature is observed, and at a horizon of 130-140 m it reaches a value of 1.4 °. In autumn, cooling of the sea surface extends to horizons of 15–20 m and evens out the temperature in this layer. From here to the horizons of 90–100 m, the water temperature is slightly higher than in the surface layer, since in the subsurface (20–100 m) horizons, the heat accumulated over the summer is still preserved. Further, the temperature drops again and from the horizons of 130-140 m to the bottom is 1.4°. In some areas of the Basin, the vertical distribution of water temperature has its own characteristics. The rivers flowing into the White Sea annually pour into it about 215 km3 of fresh water. More than 3/4 of the total flow falls on the share of rivers flowing into the Onega, Dvina and Mezen bays. In high-water years, the Northern Dvina contributes 171 km3, Mezen 38.5 km3, Onega 27.0 km3 of water per year. The Kem, which flows into the western coast, gives 12.5 km3 and Vyg 11.5 km3 of water per year. The remaining rivers provide only 9% of the runoff. The intra-annual distribution of the runoff of the rivers flowing into these bays, which in the spring discharge 60-70% of the water, is also characterized by great unevenness. In connection with the natural regulation by lakes of many coastal rivers, the distribution of their flow during the year occurs more or less evenly. The runoff maximum is observed in spring and amounts to 40% of the annual runoff. Near the rivers flowing from the southeast, the spring flood is sharper. For the sea as a whole, the maximum flow occurs in May, the minimum in February-March. Fresh waters entering the White Sea raise the water level in it, as a result, excess water flows through the Gorlo into the Barents Sea, which is facilitated by the predominance of southwestern winds in winter. Due to the difference in densities of the waters of the White and Barents Seas, a current arises from the Barents Sea. There is an exchange of water between these seas. True, the basin of the White Sea is separated from the Barents Sea by an underwater threshold located at the exit from the Gorla. Its greatest depth is 40 m, which makes it difficult to exchange deep waters between these seas. Approximately 2200 km3 of water flows out of the White Sea annually, and about 2000 km3/year flows into it. Consequently, significantly more than 2/3 of the entire mass of deep (below 50 m) White Sea water is renewed per year. At the exit from the Dvina Bay, the cold deep layers are much closer to the surface than in other areas of the Basin. A temperature of 0°C is observed here only 12-15 m from the surface. K. M. Deryugin (1928) called this region the “pole of cold” in the White Sea. Its formation is explained by the cyclonic circulation of surface waters, in the center of which the deep water rises. It seems to be sucked in from below instead of water leaving from above. The “pole of cold” is very pronounced in summer. In autumn-winter, with the development of vertical circulation, it is less noticeable. When leaving the Kandalaksha Bay, the picture is reversed: warm waters sink deep down. Zero temperature is observed at the 65 m horizon, while in other places on this horizon the temperature usually has negative values. By analogy with the first name, K. M. Deryugin (1928) called this area the “heat pole”. Its existence is associated with the influence of the influx of homogeneous and warmer, in comparison with the surrounding, deep waters from the Throat, i.e., advection of heat. This is confirmed by an increase in the thickness of surface warm waters in the area of ​​the “heat pole” in autumn, when the inflow of deep waters from the Gorlo becomes more intense. The vertical distribution of water temperature in the Throat is fundamentally different. Due to good mixing, seasonal differences consist in the change in the temperature of the entire mass of water, and not in the nature of its change with depth. In contrast to the Basin, here external thermal effects are perceived by the entire mass of water as a whole, and not from layer to layer. The salinity of the White Sea is lower than the average salinity of the ocean. Its values ​​are unevenly distributed on the sea surface, which is due to the peculiarities of the distribution of river runoff, half of which is provided by the Northern Dvina, the inflow of water from the Barents Sea, and the transfer of water by sea currents. Salinity values ​​usually increase from the tops of the bays to the central part of the Basin and with depth, although each season has its own characteristics of salinity distribution. In winter, salinity on the surface is everywhere increased. In the Throat and Funnel it is 29.0--30.0‰, and in the Basin it is 27.5--28.0‰. The mouth areas of the rivers are the most desalinated. In the Basin, the values ​​of surface salinity can be traced to horizons of 30-40 m, from where they increase sharply at first, and then gradually increase towards the bottom. In spring, surface waters are significantly desalinated (up to 23.0‰, and in the Dvina Bay up to 10.0–12.0‰) in the east and much less (up to 26.0–27.0‰) in the west. This is due to the concentration of the main part of the river runoff in the east, as well as the removal of ice from the west, where they form but do not melt, and therefore do not have a desalination effect. Reduced salinity is observed in the layer 5–10 m below; it sharply increases to horizons of 20–30 m, and then gradually rises to the bottom. In summer, salinity on the surface is lower and variable in space. A typical example of the distribution of salinity values ​​on the surface is shown in fig. 20. The range of salinity values ​​is quite significant. In the Basin, desalination extends to horizons of 10-20 m, from here the salinity first sharply and then gradually increases to the bottom (Fig. 21). In bays, desalination covers only the upper 5-meter layer, which is associated with compensatory flows that compensate for the loss of water carried by runoff surface currents. A. N. Pantyulin noted that due to the difference in the thickness of the layer of low salinity in the bays and in the Basin, the maximum of desalination, obtained by calculating the depth-integrated salinity, is associated with the latter. This means that the central part of the Basin is a kind of reservoir of relatively fresh water coming from the Dvina and Kandalaksha bays. This is a peculiar hydrological feature of the White Sea. In autumn, salinity on the surface increases due to a decrease in river flow and the beginning of ice formation. In the Basin, approximately the same values ​​are observed up to horizons of 30-40 m, from here they increase to the bottom. In the Gorlo, Onega, and Mezen bays, tidal mixing makes the vertical distribution of salinity more uniform throughout the year. The density of the White Sea water primarily determines salinity. The highest density is observed in Voronka, Gorlo and the central part of the Basin in autumn and winter. In summer, the density is reduced. Density values ​​increase quite sharply with depth in accordance with the vertical distribution of salinity, which creates a stable stratification of waters. It makes wind mixing difficult, the depth of which during strong autumn-winter storms is approximately 15–20 m, and in the spring-summer season it is limited to horizons of 10–12 m. convection in most of the sea only up to horizons of 50–60 m. Somewhat deeper (80–100 m) winter vertical circulation penetrates near the Gorlo, where this is facilitated by intense turbulence associated with strong tidal currents. The limited depth of distribution of autumn-winter convection is a characteristic hydrological feature of the White Sea. However, its deep and bottom waters do not remain in a stagnant state or extremely slow refreshment in the conditions of their difficult exchange with the Barents Sea. The deep waters of the Basin are formed annually in winter as a result of mixing of surface waters entering the Funnel from the Barents Sea and from the Throat of the White Sea. During ice formation, the salinity and density of waters mixed here increase and they slide down the slopes of the bottom from the Gorlo to the bottom horizons of the Basin. The constancy of temperature and salinity of the deep waters of the Basin is not a stagnant phenomenon, but a consequence of the uniform conditions for the formation of these waters. The structure of the White Sea waters is formed mainly under the influence of desalination by continental runoff and water exchange with the Barents Sea, as well as tidal mixing, especially in the Gorla and Mezen Bay, and winter vertical circulation. Based on the analysis of the curves of the vertical distribution of oceanological characteristics, V. V. Timonov (1950) identified the following types of water in the White Sea: Barents Sea (in its pure form are presented only in the Voronka), desalinated waters of the tops of the bays, waters of the upper layers of the Basin, deep waters of the Basin, waters Throat. The application of T, S-analysis to different areas of the White Sea allowed A. N. Pantyulin (1975) to establish the existence of two water masses in shallow (up to 50 m depth) parts of the sea. In the deep areas of the Basin and the Kandalaksha Bay, the surface layer is traced, significantly warmed up and desalinated in summer, intermediate (T = ?0.7–1.0°, S = 28.5–29.0‰) with a core in most cases at the m, deep - highly saline with a temperature close to freezing, water masses. The noted structure of the waters is a characteristic hydrological feature of the White Sea. The horizontal circulation of the White Sea waters is formed under the combined influence of wind, river runoff, tides, compensatory flows, so it is diverse and complex in detail. The resulting movement forms a counterclockwise movement of waters, characteristic of the seas of the Northern Hemisphere. Due to the concentration of river runoff, mainly in the tops of the bays, a waste current arises here, directed to the open part of the Basin. Under the influence of the Coriolis force, the moving waters are pressed against the right bank and leave the Dvina Bay along the Zimny ​​Coast to the Gorlo. At the Kola coast, there is a current from the Gorlo to the Kandalaksha Bay, from which the waters move along the Karelian coast to the Onega Bay and flow out of it near its right bank. In front of the entrance from the bays in the Basin, weak cyclonic gyres are created between the waters moving in opposite directions. These cycles cause anticyclonic movement of waters between them. Around the Solovetsky Islands, the movement of waters is traced clockwise. The velocities of constant currents are small and usually equal to 10-15 cm/s, in narrow places and near capes they reach 30-40 cm/s. Tidal currents have much higher speeds in some areas. In Gorlo and Mezensky Bay they reach 250 cm/s, in Kandalaksha - 30-35 cm/s and Onega Bay - 80-100 cm/s. In the Basin, tidal currents are approximately equal in speed to constant currents. The tides are well expressed in the White Sea. A translational tidal wave from the Barents Sea propagates along the axis of the Funnel to the top of the Mezen Bay. Passing across the entrance to the Gorlo, it causes waves passing through the Gorlo to the Basin, where they are reflected from the Summer and Karelian coasts. The addition of waves reflected from the coast and oncoming waves creates a standing wave, which creates tides in the Throat and the White Sea Basin. They have a regular semidiurnal character. Due to the configuration of the shores and the nature of the bottom topography, the highest tide (about 7.0 m) is observed in the Mezensky Bay, near the Kaninsky coast, Voronka and at about. Sosnovets, in the Kandalaksha Bay it slightly exceeds 3 m. In the central regions of the Basin, the Dvina and Onega bays, the tides are less. The tidal wave travels long distances up rivers. In the Northern Dvina, for example, the tide is noticeable 120 km from the mouth. With this movement of the tidal wave, the water level in the river rises, but suddenly it stops its rise or even drops slightly, and then continues to rise again. This process is called "maniha" and is explained by the influence of various tidal waves. In the mouth of the Mezen, which is wide open to the sea, the tide delays the river current and forms a high wave, which, like a water wall, moves up the river, its height is sometimes several meters. This phenomenon is called “rolling” here, on the Ganges - “boron”, and on the Seine - “mascara”.

The marginal sea is a body of water belonging to the mainland, but not separated or partially separated from the ocean by islands. As a rule, these are water bodies located on the slope of the mainland or on its shelf. All sea regimes, including climatic and hydrological and bottom sediments, are influenced not only by the ocean itself, but also by the mainland. Often, water bodies do not differ in depth and relief of the bottom.

The marginal seas include such as the Barents, Kara, East Siberian, Laptev Sea and others. Let's look at each of them in more detail.

Seas of Russia: marginal and inland

The Russian Federation owns a fairly large area on which rivers, lakes and seas are located.

Many historical figures of our country, after whom the water streams are named, are included in the book of world geographical history.

Russia is washed by 12 seas. They belong to the Caspian Sea, as well as 3 oceans.

All water bodies of the state can be divided into two types: marginal and internal.

Marginal seas (the list will be presented below) are mainly located near the borders of Russia. They wash the northern and eastern coasts of the country and are separated from the oceans by archipelagos, islands and island arcs.

Domestic - located on the territory of the country to which they belong. Relating to certain basins, they are located at a great distance from the oceans, while being connected to them by straits.

Russian marginal seas (list):

• Pacific Ocean: Sea of ​​Japan, Sea of ​​Okhotsk and Bering Sea.
• Arctic Ocean. Its basin includes the Laptev, Barents, Kara, East Siberian and Chukchi Seas.

Barents Sea

Belongs to the Arctic Ocean. On its shores is the Russian Federation and the Kingdom of Norway. The marginal sea has an area of ​​more than 1 thousand km2. Its depth is 600 m. Due to the strong current from the ocean, the southwest of the reservoir does not freeze.

In addition, the sea plays an important role for the state, mainly in the field of trade, catching fish and other seafood.

Kara Sea

The second marginal sea of ​​the Arctic Ocean is the Kara Sea. It has several islands. It is located on the shelf. The depth varies from 50 to 100 m. In some zone, this figure increases to 620 m. The area of ​​the reservoir is more than 883 thousand km 2.

The Ob and Yenisei flow into - two full-flowing streams. Because of this, the salinity level in it varies.

The reservoir is known for its uncomfortable climate. Here, the temperature rarely rises above 1 degree, it is constantly foggy and storms often occur. Almost all the time the reservoir is under the ice.

Laptev sea

Examples of the marginal seas of the Arctic Ocean would be incomplete without the Laptev Sea. It brings great benefits to the state and has a sufficient number of islands.

The name comes from the names of two Russian explorers (the Laptev brothers).

The climatic conditions here are quite severe. The temperature drops below zero degrees. The salinity of the water is minimal, the animal and plant world does not shine with diversity. A small number of people live on the coast. The ice here is all year round, except for August and September.

On some islands, to this day, the remains of mammoths are found, which are well preserved.

East-Siberian Sea

The sea has a bay and a port. It belongs to Yakutia. Thanks to some straits, it connects with the Chukchi Sea and the Laptev Sea. The minimum depth is 50 m, the maximum is 155 m. The salinity is kept at around 5 ppm, in some northern regions it increases to 30.

The sea is the mouth for the Indigirka. It has several large islands.

The ice is permanent. In the center of the reservoir you can see large boulders that have been here for several years. The temperature for the whole year varies from -1 0 С to +5 0 С.

Chukchi Sea

The last marginal sea of ​​the Arctic Ocean is the Chukchi Sea. Here you can often observe sharp storms and high tides. Ice comes here from the western and northern sides. The southern part of the sea is free from glaciation only in the summer season. Due to climatic conditions, in particular, strong winds, waves up to 7 m can rise. In summer, in some areas, the temperature rises to 10-12 0 С.

Bering Sea

Some marginal seas of the Pacific Ocean, such as the Bering Sea, wash not only the Russian Federation, but also the United States of America.

The area of ​​the reservoir is more than 2 million km 2. The maximum depth of the sea is 4 thousand meters. Thanks to this reservoir, the North American and Asian continents are divided into parts.

The sea is located in the North Pacific Ocean. The southern coast resembles an arc. It has several bays, capes and islands. The latter are mainly located near the USA. There are only 4 islands on the territory of Russia. Yukon and Anadyr, major rivers of the world, flow into the Bering Sea.

The air temperature is +10 0 C in summer and -23 0 C in winter. Salinity is kept within 34 ppm.

Ice begins to cover the surface of the water in September. The opening takes place in July. The Gulf of Laurentia is practically not freed from ice. also most of the time it is completely covered, even in summer. The sea itself is under ice for no more than 10 months.

The relief is different in different regions. For example, in the northeastern part, the bottom is shallow, and in the southwestern zone, it is deep. The depth rarely exceeds 4 km. The bottom is covered with sand, shells, silt or gravel.

Sea of ​​Okhotsk

The Sea of ​​Okhotsk is separated from the Pacific Ocean by Kamchatka, Hokkaido and the Kuril Islands. Washes the Russian Federation and Japan. The area is 1500 km 2, the depth is 4 thousand m. Due to the fact that the west of the reservoir is gentle, it does not deepen much. To the east is a basin. Here the depth reaches its maximum mark.

The sea is covered with ice from October to June. The southeast does not freeze due to the climate.

The coastline is indented. Some areas have bays. Most of them are in the northeast and west.

Fisheries flourish. Salmon, herring, navaga, capelin and others live here. Sometimes there are crabs.

The sea is rich in raw materials, which are produced by the state on Sakhalin.

The Amur flows into the Okhotsk basin. There are also several main ports of Russia.

The temperature in winter ranges from -1 0 С to 2 0 С. In summer - from 10 0 С to 18 0 С.

Often only the surface of the water warms up. At a depth of 50 m there is a layer that does not receive sunlight. Its temperature does not change throughout the year.

Waters with temperatures up to 3 0 C come here from the Pacific Ocean. Near the coast, as a rule, the sea warms up to 15 0 C.

Salinity is 33 ppm. In coastal areas, this figure is halved.

Japanese Sea

It has a temperate climate. Unlike the north and west, the south and east of the reservoir are quite warm. The temperature in winter in the north is -20 0 C, in the south at the same time it is +5 0 C. Due to the summer monsoon, the air is quite warm and humid. If in the east the sea warms up to +25 0 С, then in the west only up to +15 0 С.

In the autumn season, the number of typhoons, which are caused by strong winds, reaches a maximum. The highest waves reach 10 m, in emergency situations their height is more than 12 m.

The Sea of ​​Japan is divided into three parts. Two of them periodically freeze, the third does not. Tides often occur, especially in the southern and eastern parts. Salinity practically reaches the level of the World Ocean - 34 ppm.

General physical and geographical characteristics of the White Sea

The White Sea is located in the subpolar physiographic zone in the north of the European part of Russia. It connects to the Barents Sea, being part of the Arctic Ocean. Geomorphologically, the White Sea is a marginal shelf water body.
The question of the boundaries of the White Sea is solved by individual researchers ambiguously. Some authors include Funnel and Mezen Bay in its composition, while others do not. There are also different opinions on the issue of attributing the Throat to the sea area. There is also no unity in the use of such names as "bay", "bay", etc. In this regard, in this book, the "White Sea Pilot" is taken as the basis as an official source. According to it, the White Sea, located to the south and east of the Kola Peninsula, has a conditional border with the Barents Sea in the north along the line of Cape Svyatoy Nos - Cape Kanin Nos (Fig. 3.1). The area of ​​the sea is about 91 thousand km. At the same time, the share of numerous islands accounts for 0.8 thousand km. The maximum depth is 340 m, the average depth is 67 m, and the volume is 5.4 thousand km. The length of the coastline along the mainland is 5.1 thousand km, the maximum length from Cape Kanin Nos to the city of Kem is 600 km; between the cities of Arkhangelsk and Kandalaksha, the distance is 450 km.
The White Sea is most commonly divided into the following areas: Funnel, Throat, Basin and four bays - Kandalaksha, Onega, Dvina and Mezen (see Fig. 3.1).
The maritime boundaries of the Funnel are usually considered to be lines connecting Cape Kanin Nos and Svyatoy Nos in the north, and in the south, on the one hand, the mouth of the river. Ponoya and Cape Voronov, and on the other - capes Voronov and Kanushin. This last line cuts off the Szensky Bay from the Funnel. Funnel - the largest area of ​​the sea. Its area is 24.7 thousand km, volume is 855 km, average depth is 34 m. The greatest depths - up to 140 m - are located in the western part, the coastline is slightly indented, there are few islands. Ponoya and large about. Morzhovets, located on the border with the Mezen Bay.

Throat - a relatively narrow strait (width 45-55 km), connecting the northern and southern parts of the sea. In the northeast, it adjoins the Funnel, and on the other hand (in the southwest) it is limited by a line passing from the village. Tetrino on the Tersky coast to Cape Zimnegorsky - on Zimny ​​(see Fig. 3.1). The shores of the Throat are slightly indented, even. In the northwestern part of the strait lie about. Sosnovets and Danilov. There are no other islands. The Gorla area is 102 thousand km2, the volume is 380 km2, the average depth is 37 m.

The next area of ​​the sea is the Basin (see Fig. 3.1). Its maritime boundaries are the lines separating the bays. One of them, separating the Basin and the Dvina Bay, connects the Zimnegorsky and Gorboluksky capes. The other, cutting off the Onega Bay, runs between Kirbey-Navolok and Cape Gorboluksky. The line delimiting the Basin and Kandalaksha Bay connects Kirbey-Navolok with Cape Ludoshny. The area of ​​the Basin is 21.8 thousand km, the volume is 2.7 thousand km. the average depth is 125 m. The shores (Tersky in the north and Karelian in the west) are slightly indented, especially the Tersky. There are few islands: Zhizhginsky, located on the border with the Dvinsky Onega bays, and several islands near the Karelian coast.
The Mezen Bay (see Fig. 3.1) adjoins the Funnel and is bounded by the Kanushinsky and Abramovsky coasts, which are very weakly indented. There are no islands in the bay, only on the border with the Funnel there is a large island. Morzhovets. The water area of ​​the bay occupies an area of ​​56 thousand km2, a volume of 75 km2, and an average depth of 13 m. One of the largest rivers, the Mezen, flows into the apex of the bay, the waters of which carry a significant amount of suspended material. The waters of the Mezen Bay are turbid due to abundant terrigenous drift and very strong tidal currents, constantly washing and transporting the bottom material,
The Dvina Bay (see Fig. 3.1) is enclosed between the Winter and Summer coasts. The largest of the White Sea rivers, the Northern Dvina, flows into its kut. There are many islands in its huge delta. The largest of them - Mudyugsky - is located at the outlet of the estuary and closes a vast shallow lagoon - the Dry Sea. The shores of the bay are slightly indented, the only large bay is the Unskaya Bay. 49 m. Bottom sediments, as in the Basin, are mainly silts.

Onega Bay (see Fig. 3.1) is shallow (average depth is about 20 m), but the largest in area (12.3 thousand KMo). Ero volume is 235 km. The eastern coast of the bay is called Onega, and its southern part has an independent name - Lyamitsky coast. The western coast between the mouths of the Onega and Kem rivers is called Kemsky and borders on the Karelian coast. Numerous island archipelagos are located along the Pomeranian and Karelian coasts of the bay. The most significant of them are the Onega, Sumy and Kem skerries. In the middle of the bay there are two large islands - Big and Small Zhuzhmuy, and in the north - the Solovetsky archipelago.

In the west, the Kandalaksha Bay adjoins the Basin (see Fig. 3.1). Its area is 65 thousand km, volume 710 km, average depth is 100 m. In the middle of the bay, closer to the center of the sea, there is a deep-water trench with a maximum depth of about 340 m for the White Sea. The shores of the bay are indented by numerous bays. In its water area there are many islands united in archipelagos: Severny and Keretsky, Luvengsky skerries, Srednie Ludy, Kem-Ludy, etc. The largest Island is Veliky, covering the entrance to the largest White Sea lagoon - Babiye More. Kut of the Kandalaksha Bay to the north of the Middle Lud is relatively shallow, the depths do not exceed m. This part of the bay has its own name - Kandalukha.

The shores of the White Sea differ greatly in their geological and geomorphological features. The eastern coast is low-lying and geologically represents a submerged part of the Russian platform. Quaternary deposits are widespread on the southern coasts. The western coast and islands in this part of the sea are composed of metamorphic rocks, mainly of Archean granite-gneisses. The seashores in the northwest, in the area of ​​the Kandalaksha Bay, are of tectonic origin. The coast of the Kola Peninsula in many places is limited by faults.
The shores of the northern part of the White Sea are predominantly steep. The coastal heights of the Tersky coast, covered with tundra vegetation, are not very high, rocky and gradually rise inland. For the most part, the Kaninsky coast is formed by low, but steep clay cliffs, interrupted by sandy lowlands at the mouths of the rivers. The northern part of the Konushinsky coast is relatively low, and in the southern part this coast rises sharply, becomes steep and resembles Kaninsky. The Abramovsky coast, covered at the top with tundra vegetation, is low, abounds in clay and sandy scree and rises only at Cape Voronov.

The Tersky coast of the Throat is low and gentle. The winter coast of the Gorla, at Cape Voronov, is high and steep, goes down to the south to Cape Intsy, and then rises again to Cape Zimnegorsky.

The Terek coast within the Basin becomes flatter. Bedrock outcrops give way to a coastal ledge with a gently sloping coastal terrace composed of moraine material. In the region of the mouth of the river Abundant sand deposits are widespread in the Varzugs, and Cape Tolstik, better known under the ancient name Cape, or Mountain, Ship, is composed of red Riphean sandstones.

Both the Winter and the Summer coasts of the Dvina Bay are very similar almost along their entire length. They are represented by high sandy cliffs, at the top of which are forests. The coast near the Northern Dvina delta is low-lying. Onega coast between Cape Ukht-Navolok and the mouth of the river. Zolotitsa is formed by a sandy-clay cliff, gradually descending to the south. Further from the river The coast of Zolotitsa becomes low-lying and rocky. Between Cape Chesmensky and the mouth of the river. Onega coast descends to the sea in two terraces. The Pomeranian and Karelian shores of the Onega Bay are low-lying almost throughout. The Karelian coast between the Onega and Kandalaksha bays is rocky and relatively elevated, but gently descends to the sea. The shores of the Kandalaksha Bay are mostly elevated and steep. In places, the Kandalaksha coast is formed by almost sheer cliffs. The northern part of the bay is framed by the Khibiny fortresses.

The relief of the bottom of the White Sea is uneven, the depths vary greatly both between individual regions and within them. The northern part of the sea is the shallowest. Only in the north of the Funnel do depths reach 60-70 m in some places, while the main part of the water area of ​​the Mezen Bay does not go beyond the 20 m isobath. riverbed. Mezen. In front of the entrance to the Mezen Bay there are many sand banks located in several ridges and bearing the name Northern Cats. The size of the Northern Cats and the depths above them change over time under the influence of storms and tidal currents. In general, the soil of the northern part of the sea away from the coast is predominantly sandy, often with an admixture of shells.

The bottom relief of the Throat is even more indented. Elongated along the axis of the strait, erosional and accumulative troughs and ridges alternate with separate uplifts and closed basins. The longitudinal trench along the western coast of the strait is especially clearly pronounced, where the depths exceed 50 m. Rocky soils are predominant in Gorlo.

The central basin of the Basin with depths of more than 100 m extends from the northwest to the southeast (from Kandalaksha to Dvina Bay) and occupies approximately two thirds of the Basin's water area. Within the basin there are three basins separated by rapids. The depths of the basins are more than 250 m. The bottom relief in the Basin, as well as in the deep-water parts of the Kandalaksha and Dvina bays, is even, the soils are silty and silty-sandy. Only in the delta of the Northern Dvina near the western coast and at the top of the Kandalaksha Bay, along the Karelian coast, the bottom is very uneven. Onega Bay also has a complex bottom relief, where the bottom is dotted with numerous rocky banks, corgis, luds and shoals. Irregularities of the bottom relief in the surface part are manifested in the form of a large number of islands scattered almost over everything and its surface, especially in the western part of the bay. In the Onega and Kandalaksha bays, rocky soils predominate.

The Arctic Ocean (the only one located almost entirely south of the Arctic Circle), deeply incised into the land. It is located entirely within Russia. It is connected in the north with the Barents Sea by the narrow Gorlo Strait, the northern wide part of which is called the Voronka Strait, the central part of the sea is called the Basin. It borders on the Barents Sea along the line of Cape Svyatoy Nos (on the Kola Peninsula) - Cape Kanin Nos. One of the smallest seas on Earth. The area is 90 thousand km 2, the volume is 6 thousand km 3. The greatest depth is 350 m. The heavily indented coastline of the White Sea forms numerous bays (bays), the largest being Onega, Dvinskaya, Mezenskaya, Kandalaksha Bay. Large islands - Solovetsky, Veliky, Morzhovets, Oleniy, many small islands. The shores of the White Sea, which have their own names, are mostly low-lying, abrasion, with traces of glacial processing. The Tersky coast is predominantly accumulative, the Kandalaksha, Karelsky and a significant part of the Pomorsky coast are of the fjord-skerry type, most of the Onega, Summer and Winter coasts belong to the abrasion-accumulation type of leveled coasts, the Abramovsky and Konushinsky coasts of the Mezen Bay are actively eroded abrasion. Along the Konushinsky coast there are wide sandy-silty drylands (laids).

Relief and geological structure of the bottom. The White Sea basin is located partly on the margin of the Baltic Shield of the ancient East European Platform, and partly on the Russian Plate, where the Early Precambrian crystalline basement is overlain by sedimentary rocks of the Lower and Middle Paleozoic. The deepest areas of the White Sea are in the Kandalaksha Bay (over 300 m) and in the Basin (about 200 m), from which the depths gradually decrease to the top of the Dvina Bay. The remaining areas of the sea are shallow, especially the Onega and Mezen bays. In the latter, there are many sandy movable shoals called cats (for example, Northern Cats). The throat is a wide trough with depths at the threshold of about 40 m, which makes it difficult to exchange water with the Barents Sea. Bottom sediments in shallow waters and in areas with significant velocities of near-bottom currents are represented mainly by sand, pebbles, boulders, in the Basin and Dvinskaya Bay - fine-grained clayey silt; ferromanganese nodules were found in Gorlo and other areas.

Climate. The White Sea is characterized by a transitional climate from subarctic maritime to temperate continental. Winter is cold and long. Air temperatures in February average -15°C, the minimum is up to -26°C, the highest is at the outlet of the Funnel (-9°C), which is explained by the warming effect of the coastal branch of the North Cape Current in the Barents Sea. Summer is short and cool. Northeast winds bring rainy weather with a temperature in July of 8-10°C. With southwestern winds, sunny weather sets in with temperatures up to 18°C. The highest temperatures are observed in the southern part of the White Sea (up to 30°C). The annual amount of precipitation is about 600 mm. Frequent fogs.

Hydrological regime. River runoff in the White Sea averages about 215 km 3 per year. Large rivers - the Northern Dvina, Mezen, Onega, Kem and Vyg - provide over 90% of the total river flow, and up to 70% during the spring flood. Along the shores of the Kola Bay, relatively cold and salty Barents Sea waters enter the White Sea, 2000 km 3 per year. In the opposite direction along the southeastern shore of the Gorla and the eastern shore of the Funnel, White Sea waters flow out, about 2200 km 3 per year, up to 70% of the White Sea water is renewed in a year.

In the deep-water parts of the White Sea, three water masses are distinguished: surface, warmed up and rather desalinated during the warm period, intermediate (temperature from -0.7 to 1 ° C, salinity 28.5-29‰) and deep, with high salinity and temperature, close to freezing in shallow water - two.

Surface circulation is generally created by a flow that is counterclockwise. Several differently directed cycles are observed in the Basin. The speed of the currents is on average about 10-15 cm/s, in narrowings and near capes - up to 30-40 cm/s, in Gorlo and in the Mezen Bay it reaches 250 cm/s.

The tides in the White Sea are regular semi-diurnal. The highest tide at the top of the Mezen Bay is up to 10 m, in the Kandalaksha Bay it is about 3 m. Surge fluctuations in the level are most noticeable in the cold season. In autumn and winter, with northeast and northwest winds, the strongest surges are observed, up to 90 cm high, in winter and spring, with southwestern winds, the strongest surges, up to 75 cm high. The strongest waves, 4-5 points, are noted autumn in the Funnel and Throat. Waves up to 1 m high prevail, rarely up to 5 meters.

The water temperature on the surface in summer averages from 7°C at the entrance to the Funnel to 15°C in the tops of the bays, in winter from -0.5°C in the bays to -1.9°C in the Gorla. All this leads to the fact that the salinity of the surface layer over most of the sea area is significantly lower than the average oceanic one. In winter, salinity is higher than in summer, in Voronka and Gorla 29-30‰, in the Basin 27.5-28‰, in bays 23-25‰. In summer, salinity contrasts in different areas of the sea are much higher: from 34‰ in the northwestern part of the Voronka to 10‰ at the top of the Dvinskaya Bay.

The White Sea is covered with ice every winter and belongs to the seas with seasonal ice cover. At the end of October, ice appears at the top of the Mezen Bay, in January - in Voronka and Gorla. Up to 90% of all sea ice in the White Sea is drifting; landfast ice occupies a narrow coastal strip, usually no more than 1 km. The White Sea ice is constantly carried into the Barents Sea. Ice thickness is on average 35-40 cm, but in especially severe winters fast ice can freeze up to 150 cm. The destruction and melting of the ice cover usually begins at the end of March in Voronka, at the end of May - beginning of June the sea is completely freed from sea ice.

Research history. The first, not later than the beginning of the 11th century, the Novgorodians began to master the White Sea, who settled on its shores and subsequently received the name Pomors. The difficult fishing conditions forced the Pomors to study tidal phenomena, the nature of winds and sea currents, and develop their own navigation methods. The first hydrographic information about the White Sea dates back to the middle of the 16th century. The general inventory of the White Sea was made in 1798-1801. Detailed work on surveying and measurements was carried out in 1827-32 by the Russian scientist M.F. Reinecke, who published the Atlas of the White Sea. The first sailing direction of the White Sea was published in 1850. In 1891-1902, under the leadership of N. M. Knipovich, complex studies of the deep-sea part of the sea were carried out. In the 20th - early 21st centuries, the research of the White Sea is carried out with the help of a network of hydrometeorological stations, as well as expeditions of the State Committee for Hydrometeorology, the Ministry of Science and Education, the Russian Academy of Sciences, etc.

Economic use. The White Sea is rich in bioresources; the benthic fauna includes over 700 species. Of the 50 species of fish, salmon, trout, navaga, polar cod, flounder, smelt, White Sea herring and White Sea cod are of commercial importance. From the end of the 15th to the beginning of the 18th centuries, the most important sea route ran through the White Sea, connecting Russia with Western Europe. The transport significance of the White Sea has been preserved at the beginning of the 21st century. Through the White Sea-Baltic Canal (near the city of Belomorsk), it is connected to the Baltic Sea, and the Volga-Baltic Waterway - to the Volga. Main ports: Arkhangelsk, Onega, Belomorsk, Kandalaksha.

The ecological state of the White Sea is generally stable and relatively favorable. The concentration of pollutants increases in the estuarine zones of rivers, in bays, in the places where the fleet is concentrated, which leads to some reduction in the size of hydrobionts in coastal areas.

Lit .: Dobrovolsky A.D., Zalogin B.S. Seas of the USSR. M., 1982; Zalogin B.S., Kosarev A.N. Seas. M., 1999.