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Currents of the Barents Sea. Average long-term water temperature in the Barents Sea

It is located on the westernmost part of all Arctic seas. The Barents Sea is located in the North European shelf. The northern and western boundaries of the sea have a conditional line. The western border runs along Cape South, Bear, Cape North Cape. Northern - along the outskirts of the islands of the archipelago, then along a number of other islands. From the southern part, the sea is limited by the mainland and a small strait that delimits the Barents Sea from. The eastern border runs along the Vaygach Islands, and some others. The Barents Sea is a continental marginal sea.

The Barents Sea in its size occupies one of the first places among. Its area is 1 million 424 thousand km2. The volume of water reaches 316 thousand km3. The average depth is 222 m, the deepest is 600 m. New Earth, Bear and others). Small islands are mostly united in archipelagos, which are located next to the mainland or to large islands. the sea is rather uneven, complicated by various capes, bays and bays. The shores washed by the Barents Sea have a different origin and structure. The coast is Scandinavian and predominantly abruptly ending to the sea. The western coast of the island of Novaya Zemlya has. And the northern part of the island is in contact with, some of which enter the sea.

Fishing is widely developed in the Barents Sea. Cod, haddock, sea bass, herring are harvested from the waters of this sea. Near Murmansk there is a power plant that generates energy at the expense of. Also in Murmansk is the only non-freezing port of our country, which is located in the polar zone. Thus, the Barents Sea is an important sea route connecting Russia with other countries.

The open part of the Barents Sea is not heavily polluted compared to other Arctic seas. But the area where ships are actively moving is covered with a film. The waters of the bays (Kola, Teribersky, Motovsky) are subject to the greatest pollution, mainly by oil products. About 150 million m3 of polluted water enters the Barents Sea. Poisonous substances constantly accumulate in the sea soil and can cause secondary pollution.

Barencevo sea.

The Barents Sea (Norwegian: Barentshavet), until 1853 The Murmansk Sea is a marginal sea of the Arctic Ocean. It washes the shores of Russia and Norway. The sea is limited by the northern coast of Europe and the archipelagos of Svalbard, Franz Josef Land and Novaya Zemlya. The area of the sea is 1424 thousand sq. km, the depth is up to 600 m. The sea is located on the continental shelf. The southwestern part of the sea does not freeze in winter due to the influence of the North Atlantic Current. The southeastern part of the sea is called the Pechora Sea. The Barents Sea has great importance for transport and for fishing - large ports are located here - Murmansk and Vardø (Norway). Before World War II, Finland also had access to the Barents Sea: Petsamo was its only ice-free port. A serious problem is the radioactive contamination of the sea due to the activities of the Soviet / Russian nuclear fleet and Norwegian radioactive waste processing plants. IN Lately the sea shelf of the Barents Sea in the direction of Svalbard becomes the object of territorial disputes between the Russian Federation and Norway (as well as other states).

History of research.

Finno-Ugric tribes, the Saami (Lapps), have lived off the coast of the Barents Sea since ancient times. The first visits of non-autochthonous Europeans (Vikings, then Novgorodians) began, probably, at the end of the 11th century, and then intensified. The Barents Sea was named in 1853 in honor of the Dutch navigator Willem Barents. The scientific study of the sea was started by the expedition of F. P. Litke 1821-1824, and the first complete and reliable hydrological description of the sea was compiled by N. M. Knipovich at the beginning of the 20th century.

Geographical position.

The Barents Sea is the marginal water area of the Arctic Ocean on the border with Atlantic Ocean, between the northern coast of Europe in the south and the islands of Vaygach, Novaya Zemlya, Franz Josef Land in the east, Svalbard and Bear Island in the west.

Maritime borders.

In the west it borders on the Norwegian Sea basin, in the south - on the White Sea, in the east - on by the Kara Sea, in the north - with the Arctic Ocean. The area of the Barents Sea, located to the east of Kolguev Island, is called the Pechora Sea.

Coastline.

The shores of the Barents Sea are predominantly fjord-like, high, rocky, and heavily indented. The largest bays: Porsanger Fjord, Varangian Bay (also known as Varanger Fjord), Motovsky Bay, Kola Bay, etc. East of the Kanin Nos Peninsula, the coastal relief changes dramatically - the coasts are mostly low and slightly indented. There are 3 large shallow bays here: (Cheshskaya Bay, Pechora Bay, Khaipudyrskaya Bay), as well as several small bays.

archipelagos and islands.

There are few islands within the Barents Sea. The largest of them is Kolguev Island. From the west, north and east, the sea is bounded by the Svalbard, Franz Josef Land and Novaya Zemlya archipelagos.

Hydrography.

The largest rivers flowing into the Barents Sea are Pechora and Indiga.

currents.

The surface currents of the sea form a counterclockwise circulation. Along the southern and eastern periphery, the Atlantic waters of the warm North Cape current (a branch of the Gulf Stream system) move east and north, the influence of which can be traced to the northern shores of Novaya Zemlya. The northern and western parts of the circulation are formed by local and Arctic waters coming from the Kara Sea and the Arctic Ocean. In the central part of the sea there is a system of intracircular currents. The circulation of sea waters changes under the influence of changes in winds and water exchange with adjacent seas. Of great importance, especially near the coast, are tidal currents. The tides are semi-diurnal, their greatest value is 6.1 m near the coast of the Kola Peninsula, in other places 0.6-4.7 m.

Water exchange.

Water exchange with neighboring seas is of great importance in the water balance of the Barents Sea. During the year, about 76,000 cubic meters of water enters the sea through the straits (and the same amount leaves it), which is approximately 1/4 of the total volume of sea water. The largest amount of water (59,000 cubic meters per year) is carried by the warm North Cape current, which has an exceptionally great influence on the hydrometeorological regime of the sea. The total river runoff into the sea is on average 200 km3 per year.

Salinity.

The salinity of the surface layer of water in the open sea during the year is 34.7-35.0% in the southwest, 33.0-34.0% in the east, and 32.0-33.0% in the north. In the coastal strip of the sea in spring and summer, salinity decreases to 30-32%, by the end of winter it increases to 34.0-34.5%.

Geology.

The Barents Sea occupies the Barents Sea Plate of the Proterozoic-Early Cambrian age; anteclise bottom elevations, depressions - syneclises. Of the shallower landforms, there are remnants of ancient coastlines, at depths of about 200 and 70 m, glacial-denudation and glacial-accumulative forms, and sand ridges formed by strong tidal currents.

Bottom relief.

The Barents Sea is located within the continental shallows, but, unlike other similar seas, most of it has a depth of 300-400 m, an average depth of 229 m and a maximum depth of 600 m. depth 63 m)], depressions (Central, maximum depth 386 m) and trenches (Western (maximum depth 600 m) Franz Victoria (430 m) and others). The southern part of the bottom has a depth of mostly less than 200 m and is distinguished by a leveled relief.

Soils.

From the cover of bottom sediments in the southern part of the Barents Sea, sand prevails, in some places - pebbles and crushed stone. On the heights of the central and northern parts of the sea - silty sand, sandy silt, in depressions - silt. An admixture of coarse clastic material is noticeable everywhere, which is associated with ice rafting and the wide distribution of relict glacial deposits. The thickness of precipitation in the northern and middle parts is less than 0.5 m, as a result of which ancient glacial deposits practically on the surface. slow pace sedimentation (less than 30 mm in 1 thousand years) is explained by an insignificant influx of terrigenous material - due to the characteristics of the coastal relief, not a single large river flows into the Barents Sea (except for the Pechora, which leaves almost all of its alluvium within the Pechora Estuary), and the land shores composed mainly of strong crystalline rocks.

Climate.

The climate of the Barents Sea is influenced by the warm Atlantic Ocean and the cold Arctic Ocean. Frequent intrusions of warm Atlantic cyclones and cold Arctic air determine the great variability of weather conditions. In winter, southwest winds prevail over the sea, in spring and summer - northeast winds. Frequent storms. The average air temperature in February varies from -25 °C in the north to -4 °C in the southwest. The average temperature in August is 0 °C, 1 °C in the north, 10 °C in the southwest. Cloudy weather prevails over the sea during the year. Annual rainfall varies from 250 mm in the north to 500 mm in the southwest.

Ice cover.

severe climatic conditions in the north and east of the Barents Sea determine its large ice cover. In all seasons of the year, only the southwestern part of the sea remains free of ice. The ice cover reaches its greatest distribution in April, when about 75% of the sea surface is occupied by floating ice. In extremely unfavorable years at the end of winter, floating ice comes directly to the shores of the Kola Peninsula. The least amount of ice occurs at the end of August. At this time, the ice boundary moves beyond 78°N. sh. In the northwest and northeast of the sea, ice usually stays all year round, but in some favorable years the sea is completely free of ice.

Temperature.

The inflow of warm Atlantic waters determines the relatively high temperature and salinity in the southwestern part of the sea. Here, in February - March, the water temperature on the surface is 3 °C, 5 °C, in August it rises to 7 °C, 9 °C. North of 74° N. sh. and in the southeastern part of the sea in winter the surface water temperature is below -1 °C, and in summer in the north 4 °C, 0 °C, in the southeast 4 °C, 7 °C. In summer, in the coastal zone, the surface layer of warm water 5-8 meters thick can warm up to 11-12 °C.

Flora and fauna.

The Barents Sea is rich various types fish, plant and animal plankton and benthos. Seaweeds are common off the south coast. Of the 114 species of fish living in the Barents Sea, 20 species are the most important for commercial purposes: cod, haddock, herring, sea bass, catfish, flounder, halibut, etc. Mammals are found: polar bear, seal, harp seal, beluga whale, etc. Seals are hunted. Bird colonies abound on the coasts (guillemots, guillemots, kittiwakes). In the 20th century, the king crab was introduced, which was able to adapt to new conditions and begin to multiply intensively. Many different echinoderms are distributed along the bottom of the entire water area of the sea, sea urchins and starfish, different types.

Hydrological regime of the Barents Sea - Temperature map of the Barents Sea

The hydrological regime of the Barents Sea is very diverse and is formed as a result of the circulation of waters of various origins and with different properties: 1. warm waters coming from the North Atlantic Ocean; 2. warm waters of river origin; 3. relatively cold local waters 4. cold polar waters.

In the previous section, it was shown that thermohaline conditions in the Barents Sea are formed under the influence of both heat advection by currents and radiation factors. Some elements of this influence determine the stability of the climatic characteristics of temperature and salinity, while others (for example, the nonstationarity of currents and ice conditions) form their spatial and temporal variability.

Let us consider the structure of the temperature and salinity fields in their annual course, as well as the main processes that determine their distribution.

6.1. Water temperature. In the Barents Sea, the water temperature to a much greater extent than in other Arctic seas determines all processes associated with the density structure of water (convection, formation of a shock layer, etc.). In addition, in the Barents Sea, water temperature is the main indicator characterizing the distribution of warm Atlantic waters, which, in turn, determine the ice conditions and climate of the Atlantic sector of the Arctic.

The thermal regime of the Barents Sea is formed under the influence of a number of processes, of which the leading ones are autumn-winter convection, which equalizes the temperature from the surface to the bottom, and summer heating of the surface layer, which causes the emergence of a seasonal thermocline.

A large influx of warm Atlantic waters makes the Barents Sea one of the warmest in the Arctic Ocean. A significant part of the sea from the coast to 75°N. It does not freeze all year round and has positive surface temperatures. The influence of the advection of the heat of the Atlantic waters is especially noticeable in the southwestern part of the sea and insignificant in the southeast due to shallow depths in this area. here it reaches 8°C.

In the surface layer, the maximum temperature is observed in the southwestern part of the sea (9°C in June-September), the minimum (0°C) is at the ice edge. From July to October, the region of maximum temperatures also extends to the southeastern part of the sea, the position of the isotherms becomes close to the latitudinal one (Fig. 2).

Figure 2. Average long-term surface water temperature in summer and winter.

The seasonal change in water temperature is generally small, in the southwest and in the northern part of the sea it does not exceed 5-6°C and only in the southeast does it reach 10°C. in the Atlantic water mass in the extreme south-west of the sea, the surface water temperature in winter does not fall below 3°C and does not exceed 6°C, in summer it ranges from 7 to 13°C. In areas where ice is likely to occur, the absolute minimum is limited to a freezing point of -1.8°C. Summer maximum temperatures in the surface layer reach 4-7°C in the northwestern part of the sea, 15°C in the southeast in the open part of the sea, and 20-23 in the Pechora Bay.

With depth, fluctuations in water temperature decrease. IN southeastern parts of the sea at a 50 m horizon, they are about 2/3 of their value on the surface.

The distribution of water temperature on the underlying horizons reflects the development of convection processes (in winter) and summer heating in the sea. IN summer period a seasonal thermocline is formed, which begins with the transition of the heat balance of the sea surface to positive values and continues until August-September, when the depth of the shock layer reaches such values at which mixing in the surface layer can no longer significantly affect the conditions in the thermocline layer. In most of the water area of the Barents Sea, the thickness of the quasi-homogeneous layer and the depth of the upper boundary of the thermocline reach 30 m by this time, and the largest gradients fall on the 30-50 m layer.

On southwest sea, the maximum water temperature gradients do not exceed 0.1°C/m, and in the rest of its deep water area they reach 0.2°C/m; in the southeastern part of the sea and in coastal areas, the maximum gradients fall on the layer 10-25 and 0-10 m and amount to 0.4°С/m

To a large extent, the temperature distribution in the water column of the Barents Sea depends on the penetration of warm Atlantic waters, on winter cooling and on the bottom topography. Therefore, the change in water temperature along the vertical occurs unequally.

In the southwestern part, which is most affected by Atlantic waters, the temperature gradually and within small limits decreases with depth, remaining positive to the very bottom. In the north-east of the sea in winter, the negative temperature extends to the horizon of 100-200 m, deeper it rises to +1°C. In summer, the sea surface has a low temperature, which quickly drops to 25-50 m, where the low temperatures (-1.5°С) achieved during winter cooling are preserved. Below, in the layer of 50-100 m, not affected by the winter vertical circulation, the temperature increased to -1°C. Thus, between 50 and 100 m there is a cold intermediate layer. In those depressions where warm waters do not penetrate and strong cooling occurs, for example, the Novaya Zemlya Trench, the Central Basin, etc., the water temperature is uniform throughout the thickness in winter, and in summer it drops from small positive values on the surface to -1.75 ° C at the bottom .

Underwater heights serve as obstacles to the movement of Atlantic waters, so the latter flow around them. In places of flow around elevations low temperatures rise close to the surface of the water. In addition, above the hills and on their slopes, the water cools more. As a result, "cold water caps" characteristic of the banks of the Barents Sea are formed.

In the Central Highlands in winter, the water temperature is equally low from the surface to the bottom. In summer it decreases with depth and in the layer of 50-100 m has the minimum values. Below, the temperature rises again, but remains negative all the way to the bottom. Thus, here, too, there is an intermediate layer of cold water, but it is not underlain by warm Atlantic waters. In the southeastern part of the sea, temperature changes with depth have a pronounced seasonal course.

In winter, the temperature of the entire water column is negative. In spring, the upper 10-12-meter layer is covered with heating, below its temperature drops sharply to the bottom. In summer, the warming of the surface layer reaches its greatest values; therefore, the decrease in temperature between the horizons of 10 and 25 m occurs with a sharp jump. In autumn, cooling equalizes the temperature throughout the layer, which becomes almost vertically uniform by winter.

Figure 4 shows the vertical profiles of water temperature in four regions (western, northern, near Novaya Zemlya and northeastern Fig. 3), characterizing the period of formation and destruction of the thermocline (May-November). It can be seen from them that despite the significant differences in the hydrological regime of the regions, they are characterized by a number of common patterns, in particular, the delay in the annual maximum of water temperature with increasing depth and a slower drop in temperature in autumn compared to spring growth. Under real conditions, these generalized water temperature distribution profiles are complicated by the existence of diurnal and synoptic thermoclines, uneven heat advection, internal waves, the influence of river runoff, and ice melting. For example, in the southeastern part of the sea in July, at a horizon of 10 and 20 m, a significant decrease in water temperature is observed, due to the fact that in June-July this area is characterized by a pronounced density stratification, due to the inflow of a large volume of river waters.
In summer, changes in water temperature in layers with different vertical gradients are practically unrelated. The exceptions are the wind mixing layer (0-10 m) and the seasonal thermocline layer (20-30 or 30-50 m), there is no connection between these layers.

The characteristic values of water temperature fluctuations due to tidal variability are 0.2–0.5°C in a uniform

The Barents Sea is located on the North European shelf, almost open to the Central Arctic Basin and open to the Norwegian and Greenland seas, it belongs to the type of continental marginal seas. This is one of the largest seas in terms of area. Its area is 1424 thousand km2, volume - 316 thousand km3, average depth - 222 m, maximum depth - 513 m.

There are many islands in the Barents Sea. Among them are the archipelagos of Svalbard and Franz Josef Land, Novaya Zemlya, the Islands of Hope, and others. Small islands are mainly grouped into archipelagos located near the mainland or larger islands. The complex dissected coastline forms numerous capes, fjords, bays, bays. Separate sections of the Barents Sea coast belong to different morphological types of coasts. Similar shores are found on Franz Josef Land and on the island of North-Eastern Land of the Svalbard archipelago.

The position of the Barents Sea at high latitudes beyond the Arctic Circle, direct connection with and the Central Arctic Basin determine the main features of the climate. In general, the climate of the sea is polar maritime, characterized by long winters, short cold summers, small annual changes, large.

In the northern part of the sea, arctic air dominates, in the south - air of temperate latitudes. On the border of these two main streams, the Arctic front passes, directed, in general, from through Medvezhiy Island to the northern tip of Novaya Zemlya. Cyclones and anticyclones often form here, affecting the nature of the weather in the Barents Sea.

River runoff in relation to the area and volume of the sea is small and equals an average of 163 km3 per year. 90% of it is concentrated in the southeastern part of the sea. The largest rivers of the Barents Sea basin carry their waters to this region. The Pechora River discharges about 130 km3 of water in an average year, which is approximately 70% of the total coastal runoff into the sea per year. Several small rivers also flow here. The northern coast and coast account for only about 10% of the runoff. Here, small mountain-type rivers flow into the sea. The maximum continental runoff is observed in spring, the minimum - in autumn and winter.

The determining influence on the nature of the Barents Sea is exerted by water exchange with neighboring seas and, mainly, with warm Atlantic waters. The annual inflow of these waters is approximately 74 thousand km3. They bring about 177.1012 kcal of heat to the sea. Of this amount, only 12% is absorbed during the exchange of the waters of the Barents Sea with other seas. The rest of the heat is spent in the Barents Sea, so this is one of the most warm seas.

Four water masses are distinguished in the structure of the waters of the Barents Sea:

1. Atlantic waters (from the surface to the bottom), coming from the southwest, north and northeast from the Arctic basin (from 100 - 150 m to the bottom). These are warm and salty waters.

2. Arctic waters entering in the form of surface currents from the north. They have a negative temperature and low salinity.

3. Coastal waters coming with continental runoff from and with coastal currents along the coasts of Norway and the Norwegian Sea.

4. Barents Sea waters, formed in the sea itself as a result of the transformation of Atlantic waters and under the influence of local conditions.

Surface water temperatures generally decrease from the southwest to the northeast. Due to good communication with the ocean and low continental runoff, the salinity of the Barents Sea differs little from the average salinity of the ocean. The general circulation of the waters of the Barents Sea is formed under the influence of the inflow of water from neighboring basins, the bottom topography, and other factors. As in the neighboring seas of the northern hemisphere, the general movement prevails here surface water counterclock-wise. The currents of the Barents Sea are significantly affected by large-scale baric fields and local cyclonic and anticyclonic gyres. The highest speed of tidal currents (about 150 cm/s) is noted in the surface layer. High velocities are characteristic of tidal currents along the Murmansk coast, at the entrance to the White Sea Funnel, in the Kanin-Kolguevsky region and in the South Spitsbergen shallow water. Strong and prolonged winds cause surge fluctuations in the level. They are most significant (up to 3 m) near the Kola coast and near Svalbard (about 1 m), smaller values (up to 0.5 m) are observed off the coast of Novaya Zemlya and in the southeastern part of the sea. The Barents Sea is one of the Arctic Seas, but it is the only one of the Arctic seas that, due to the influx of warm Atlantic waters into its southwestern part, never completely freezes. Ice formation in the sea begins in September in the north, in October in the central regions, and in November in the southeast. The sea is dominated by floating ice, among which there are icebergs. They usually concentrate near Novaya Zemlya,

located on the North European shelf, almost open to the Central Arctic basin and open to the Norwegian and Greenland seas, it belongs to the type of continental marginal seas. This is one of the largest seas in terms of area. Its area is 1424 thousand km2, volume - 316 thousand km3, average depth - 222 m, maximum depth - 513 m.

There are many islands in the Barents Sea. Among them are the archipelagos of Svalbard and Franz Josef Land, Novaya Zemlya, the islands of Nadezhda, Kolguev and others. Small islands are mainly grouped into archipelagos located near the mainland or larger islands. The complex dissected coastline forms numerous capes, fjords, bays, bays. Separate sections of the Barents Sea coast belong to different morphological types of coasts. Similar shores are found on Franz Josef Land and on the island of North-Eastern Land of the Svalbard archipelago.

The bottom of the Barents Sea is a complexly dissected underwater plain, somewhat inclined to the west and northeast. The deepest areas, including the maximum depth, are located in the western part of the sea. The bottom topography, in general, is characterized by the alternation of large structural elements - underwater hills and trenches with different directions, as well as the existence of numerous small (3-5 m) irregularities at depths of less than 200 m and terrace-like ledges on the slopes. The difference in depths in the open part of the sea reaches 400 m. The rugged bottom relief significantly affects the hydrological conditions of the sea.
The position of the Barents Sea at high latitudes beyond the Arctic Circle, direct connection with the Atlantic Ocean and the Central Arctic Basin determine the main features of the climate. In general, the climate of the sea is polar maritime, characterized by long winters, short cold summers, small annual changes in air temperature, and high relative humidity.

In the northern part of the sea, arctic air dominates, in the south - air of temperate latitudes. At the border of these two main streams, there is an atmospheric Arctic front, directed, in general, from Iceland through Bear Island to the northern tip of Novaya Zemlya. Cyclones and anticyclones often form here, affecting the nature of the weather in the Barents Sea.

River runoff in relation to the area and volume of the sea is small and equals an average of 163 km3 per year. 90% of it is concentrated in the southeastern part of the sea. The largest rivers of the Barents Sea basin carry their waters to this region. The Pechora River discharges about 130 km3 of water in an average year, which is approximately 70% of the total coastal runoff into the sea per year. Several small rivers also flow here. The northern coast of Norway and the coast of the Kola Peninsula account for only about 10% of the runoff. Here, small mountain-type rivers flow into the sea. The maximum continental runoff is observed in spring, the minimum - in autumn and winter.

Four water masses are distinguished in the structure of the waters of the Barents Sea:

1. Atlantic waters (from the surface to the bottom), coming from the southwest, north and northeast from the Arctic basin (from 100 - 150 m to the bottom). These are warm and salty waters.

2. Arctic waters entering in the form of surface currents from the north. They have a negative temperature and low salinity.

3. Coastal waters coming with the continental runoff from the White Sea and with the coastal current along the coasts of Norway and the Norwegian Sea.

4. Barents Sea waters, formed in the sea itself as a result of the transformation of Atlantic waters and under the influence of local conditions.

Surface water temperatures generally decrease from the southwest to the northeast. Due to good communication with the ocean and low continental runoff, the salinity of the Barents Sea differs little from the average salinity of the ocean. The general circulation of the waters of the Barents Sea is formed under the influence of the inflow of water from neighboring basins, the bottom topography, and other factors. As in the neighboring seas of the northern hemisphere, the general movement of surface waters counterclockwise prevails here. The currents of the Barents Sea are significantly affected by large-scale baric fields and local cyclonic and anticyclonic gyres. The highest speed of tidal currents (about 150 cm/s) is noted in the surface layer. High velocities are characteristic of tidal currents along the Murmansk coast, at the entrance to the White Sea Funnel, in the Kanin-Kolguevsky region and in the South Spitsbergen shallow water. Strong and prolonged winds cause surge fluctuations in the level. They are most significant (up to 3 m) near the Kola coast and near Svalbard (about 1 m), smaller values (up to 0.5 m) are observed off the coast of Novaya Zemlya and in the southeastern part of the sea. The Barents Sea is one of the Arctic Seas, but it is the only one of the Arctic seas that, due to the influx of warm Atlantic waters into its southwestern part, never completely freezes. Ice formation in the sea begins in September in the north, in October in the central regions, and in November in the southeast. The sea is dominated by floating ice, among which there are icebergs. They usually concentrate near Novaya Zemlya, Franz Josef Land and Svalbard.

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