All about sharks. Kara Sea
The southern part of the sea is bounded by the mainland, in the west by several islands (Novaya Zemlya, Severnaya Zemlya), from the north the island is Vize Land.
This marginal sea is located on the continental shelf, so it is classified as a continental type.
The Kara Sea is the largest of all seas. Its area reaches 883t. km2, and the volume of water is 100 tons. km3.
The relief of the bottom of the sea
The average depth reaches 110 m, but mostly it is just over 50 m. One of the deepest places is 620 m deep. Two comparatively deep trenches run from north to south. This is St. Anna's trench, where the maximum depth is 620m and Voronin (depth is 410m). Not far from the islands of Novaya Zemlya is the East Novaya Zemlya Trench (depth up to 400m). Between these trenches is the Kara Plateau.
The bottom of the plateau is covered with sandy silt and sand, and gray, blue and brown silt is found in troughs and basins.
There are many islands in the sea, which are united in archipelagos (Skerries, Nordenskiöld, Minin). They are close to the coastline. And the large islands are located alone (Sibiryakov, Shokalsky, Nansen, Bely, Russian).
The Kara Sea ... From the course of school geography, we know that it is located somewhere on the edge of the Arctic Ocean, i.e. at the top of a map or globe. Quite a lot of knowledge, isn't it? This is definitely not enough for such an amazing geographical feature. Let's try to get to know each other better.
Section 1. Kara Sea. general description.
The Kara Sea belongs to the category of marginal seas geographically belonging to the Arctic Ocean. Its name comes from the latter, which belongs to this basin, in turn, received this name in honor of a noble local Nenets family.
Prior to this, other names can be traced in history: Northern Tatar, New Northern and Mangazeya.
In accordance with the physical and geographical conditions, the Kara is considered the most difficult sea in the Russian Arctic, so any navigation here is associated with rather great difficulties. One of the reasons is the almost constant presence of a strong ice cover. In addition, the depth of the sea is uneven, shoals are encountered quite often, and the currents are poorly studied.
It is impossible not to note the fact that much in this region is decided by the weather, and since fog or haze persists almost constantly, it is impossible to visually determine the distance in most cases.
To the south-west. part of the Kara Sea, large offshore deposits of gas condensate and natural gas.
The main economic significance of the sea lies in the fact that it is considered the most important link of such a necessary for the country and plays an important role in the development and strengthening of the productive forces of the regions.
Section 2. Kara Sea. How diverse is its flora and fauna.
On the whole, it can be said with certainty that the flora and fauna here were formed under the influence of conditions very different in nature, both climatic and hydrological. Note that they differ significantly from each other in the southern and northern parts.
Neighboring basins continue to exert enormous influence. So, for example, some heat-loving forms actively penetrate from the Barents Sea, and, on the contrary, high arctic forms from the Laptev Sea. The ecological boundary of distribution, according to scientists, is the eightieth meridian. However, one should not forget that freshwater elements also play a significant role.
If you spend comparative analysis, it turns out that qualitatively the flora and fauna are significantly poorer than the same Barents Sea, but significantly ahead of the Laptev Sea. For example, in the Barents Sea today there are 114 different species of fish, in the Kara Sea - somewhere around 54, and in the Laptev Sea - much less, only 37.
Thanks to this fact, the Kara Sea is of great importance in the life of the whole country. Omul, muksun, vendace, smelt, saffron cod, saithe and nelma are organized here.
The Kara Sea... Photos of animals living in its vicinity adorn the printed and virtual editions of the planet. Pinnipeds are also abundant in the sea. Here you can meet seals, and if you're lucky, then walruses. In the summer, the beluga whale comes here, and the polar bear lives all year round.
Section 3. Kara Sea. Interesting Facts.
The salinity of the sea is quite uneven. This is due to the fact that several large rivers flow into it at once (Yenisei, Taz and Ob). It is located mainly on the shelf. To meet an island in the Kara Sea, or rather a cluster of several, is not such a rarity. The average depth is 50-100 m, the largest recorded is 620 m. The area is 893,400 km². The coldest of all our (Russian) seas. The water temperature near the coast rarely exceeds -1.8 °C in winter, and +6 °C in summer. During the Cold War, this sea was a place for secret burial of nuclear waste. According to very rough estimates, today in its waters there are not only thousands of containers, about twenty ships with radioactive waste, but also several reactors with the most dangerous unspent fuel. It turns out that the waste, the level of radiation of which was considered low, was simply poured into the water.
Kara Sea used to be called Nyarzomsky (Narzemsky) - this is how it was named in the story of 1601 about the trip to Mangazeya by a resident of Pinega Leonty Shubin (Plekhan) and in the petition of Andrei Palitsyn from 1630. On the map of Edward Wells, the sea is called Tartar. And the name "Kara" belonged to Baydaratskaya Bay, after the name of the river Kara flowing into it. According to the version given by V.Yu. Vize, the name of the river comes from the Nenets word "hare", meaning hummocky ice. It is curious that the Dutchman N. Witsen calls the sea Ice, and the Frenchman J. Campredon Arctic, which echoes the Nenets word. For the first time, the sea was named Kara on the map of V. M. Selifontov in 1736, compiled according to the results of the work of the Dvina-Ob detachment of the Great Northern Expedition.
The Kara Sea belongs to the group of seas of the Siberian Arctic. The boundaries of this sea are land and conditional lines. From the west, the sea is bounded by a number of islands (the largest of which New Earth) and several straits. From the east, the border of the sea runs along the Severnaya Zemlya archipelago and the straits: the Red Army, Shokalsky and Vilkitsky. From the south, the border of the sea is the coast of the mainland. The Kara Sea is well open to the waters of the Arctic Ocean. The sea is located mainly on the continental shelf. These features make it possible to attribute the sea to the continental type of marginal seas.
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The Kara Sea is one of the largest seas Russian Federation. Its area is approximately 883 thousand km2. The volume of water reaches about 98 thousand km3. The average depth of the sea is 111 m, the maximum is 620 m. There are a large number of islands in the waters of the Kara Sea, most of which are small in size. Small islands are combined into archipelagos (Nordenskiöld, Skerries, Minin) and are located along the coast of the mainland. Larger islands (Bely, Shokalsky, Vilkitsky, Sibiryakov, Nansen, Russian) are located alone.
The coastline of the Kara Sea is uneven. The shores of Novaya Zemlya, which wash the waters of this sea, are indented big amount fjords. The mainland coast is also strongly dissected: in a number of places the sea sharply protrudes into the land, forming the Baidaratskaya and Obskaya bays. The Yamal Peninsula strongly protrudes into the space of the sea. Along the coastline there are large bays (Gydansky, Yeniseisky and Pyasinsky), as well as a number of small bays.
seafaring
The date of commencement of navigation in the Kara Sea is unknown. Only the fact is recorded in history that in 1556 the English traveler Stephen Borough found among the Russian sailors he met at the Kara Gates a clear idea of the sea route to the mouth of the Ob and full readiness to accompany the British along it. There is a reply from the Tobolsk governor M.M. Godunov and I.F. Volkonsky to the Tsar from 1601, where a description of this path is given: by the Yugorsky Shar Strait to the western part of Yamal, then along the Mutnaya River (a tributary of the Mordyyakha) to the watershed with the Seyakha (Green) River - Lakes Neito and Yambuto - then descent into the Ob Bay by portage and river . From the Ob Bay, a path opened south along the Ob (Obdorsk) and east through the Taz Bay (Mangazeya) to the Yenisei basin.
Bottom relief
The relief of the bottom of the Kara Sea has a large number of irregularities. The sea lies almost entirely on the shelf with depths of up to 100 meters. The St. Anna Trough has a maximum depth of 620 meters. The bottom of shallow waters and uplands is covered with sands and sandy silt. Troughs and basins are covered with gray, blue and brown muds. Iron-manganese nodules are found at the bottom of the central part of the sea.
In the southwestern part of the sea, off the Yamal Peninsula, large offshore deposits of natural gas and gas condensate have been explored. The largest of them are Leningradskoye gas reserves - more than 1 trillion m³ and Rusanovskoye. The development of offshore fields is planned to begin after 2025.
Climate and hydrological regime
The Kara Sea is characterized by a polar maritime climate, which is due to the northern location of the sea and its direct contact with the ocean. The Atlantic Ocean, located relatively close to the Kara Sea, moderates the climate. But the island of Novaya Zemlya prevents the penetration of a large amount of warm air masses. The Kara Sea is in more severe climatic conditions than the Barents Sea. Due to the large extent of the sea, climatic differences are observed in its different parts. Storms most often occur in the western part of the sea. A hurricane-force wind (Novaya Zemlya bora) constantly arises near the island of Novaya Zemlya. The duration of this hurricane is short 2 - 3 hours, but in winter time it may take several days. In March, the average air temperature reaches -28.6 0 C at Cape Chelyuskin and -20 0 C at Cape Zhelaniya. The most low temperature air that can be at sea is - 45 - 50 0 С. In the warmest period (in July), the air warms up on average by 5 - 6 0 С in the western part of the sea and by 1 - 2 east. Near the mainland coast, the air can warm up to +18 and +20 0 C. But, despite the high summer temperature, snow can fall at any summer time. In general, the short summer is marked by low temperatures and cloudy weather with a lot of rain.
The water temperature near the sea surface in winter is close to −1.8 °C. Water in shallow areas is well mixed from the surface to the bottom and has the same temperature and salinity (about 34 ppm). River runoff and melting ice in the summer lead to a decrease in the salinity of sea water below 34 ppm, in the mouths of the rivers the water becomes close to fresh. The water warms up to 6 °C in summer.
The tides in the Kara Sea reach a height of 50 - 80 centimeters. IN cold period sea ice has a great influence on the tides - the magnitude of the tide decreases. The sea is covered with ice almost all year round. Ice formation begins in September. There are large spaces multi-year ice up to 4 meters thick. Fast ice forms along the coast, and floating ice forms in the center of the sea. In summer, the ice breaks up into separate massifs.
Flora and fauna
The flora and fauna of the Kara Sea is poorer than the Barents Sea, but much richer than the Laptev Sea. The flora is represented by several types of bottom algae - brown algae, red algae, green algae. The water feels good and a lot of unicellular algae and phytoplankton develop. The fauna of invertebrates and fish is quite richly represented, including pink salmon, chum salmon, chinook salmon, sockeye salmon, omul, muksun, nelma, char, saffron cod, flounder. Salmon and whitefish spawn in rivers, and go out to sea to feed. At the same time, they keep near the mouths of the rivers, not moving far to the north. In total, 54 species of fish live in the Kara Sea. Of the marine mammals, seals, walruses, sea hare, white whales live here. Cetaceans are also represented by larger animals - minke whales, of which 5 species can be counted here. Very rarely, both bowhead whales and predatory killer whales swim here from the Barents Sea. There are many birds on the islands (guillemots, auks, little auks predominate), which form noisy bird colonies. Of the land animals, the shores of the mainland and the island are visited by the polar bear and the arctic fox, for which the sea is an important source of food. Sharks in the Kara Sea are represented by a single species - a small-headed or polar shark, which does not care about cold waters and a harsh climate.
Economic importance
The Kara Sea is characterized by high bioproductivity. Among the objects of fishing are cod, whitefish, char, vendace, omul, smelt, saffron cod, polar cod. Fisheries are organized only in bays, gulfs and lower reaches of rivers, where there is no thick ice cover. As in all coastal northern seas of Eurasia, walruses are harvested in the Kara Sea, but only for the needs of the local population, since walruses have been taken under state protection since 1956. Large oil and gas fields (gas condensate Rusanovskoye, Leningradskoye) have been discovered and are being developed. The Kara Sea is part of the transport Northern Sea Route. Ports are located here: Dikson, Amderma; Dudinka and Igarka (Yenisei).
Ecology
The waters belonging to the bays of the Kara Sea are characterized by specialists as moderately polluted. The rivers that flow into the Kara Sea have a relatively low level of pollution. However, the waters of the Ob and Yenisei have a high concentration of heavy metals, which adversely affects the ecosystem of the sea. Another important source is pollution of the waters of the water area with aerosol materials from the metallurgical production in the city of Norilsk. Vessels have a negative impact on the ecological state of the sea. The places of their frequent movement are polluted with oil products.
Remains important environmental problem Radioactive contamination of the Kara Sea. Due to the fact that a number of numerous air, surface, underground and underwater nuclear explosions were carried out on Novaya Zemlya in the 60s of the last century, more than 13 million curies of Cs-137 were released into the atmosphere. period in the northern seas began the disposal of radioactive waste. To date, the eastern part of the Novaya Zemlya shelf is the main burial site. In this region, waste is flooded in several areas at a depth of 12 to 380 m, they account for 70% of the volume of marine burials of the USSR period. In the shallow waters of the bays of the Kara Sea during 1965-1988, floating facilities with radioactive waste were flooded. The greatest potential danger comes from 17 reactors of the atomic icebreaker "Lenin" and 11 thousand containers with hazardous waste. Control measurements are regularly carried out, the results of which show that at the moment the level of radioactivity in the bays of the Kara Sea does not exceed the norm, however, these objects pose a potential environmental hazard.
Surrounded by many islands, among which, for example, Novaya Zemlya, on the northern coast of Eurasia, the Kara Sea is conveniently located, into which the Ob, Taz and Yenisei flow, where an abundant number of fish live, there is a white whale and a polar bear. The sea changed its name more than once, and was not only Kara, but also Narzem, Nyarzom, Tartar, Arctic, Ice. The history of its origin is connected with the last ice age, when the increase and decrease of ice sheets was carried out. The sea appeared on the map in 1736. Today it is a particularly significant object in the Russian Federation.
Territory of the Kara Sea in Russia
The average depth of the Kara Sea is from 50 to 100 meters, the maximum depth is 620 meters. The area is about 900 thousand km², the volume is about 100 thousand km².
In fact, the reservoir is located on a plume with a depth of less than 100 m, which is cut in the direction from north to south by the trenches of St. Anna and Voronin. The East Novaya Zemlya Trench runs along the eastern coast of Novaya Zemlya. In the area between the gutters, the Central Plateau is comfortably located with a total depth of less than 50 m.
The reservoir is one of the coldest seas in our country. Near the mouths of the rivers, the temperature values of the water in warm season year exceeds 0 °C. In winter, these values drop to almost 2°C, which is essentially the freezing point. Fog often forms over the surface of the sea, storms are also a constant companion here. The degree of salinity of water varies over a wide range.
In the eastern region of the reservoir there is the Great Arctic Reserve with rare fauna and flora - flower plants, birds, fish and mammals.
The saturation of the Kara reservoir with fauna and flora in many respects exceeds the Laptev Sea. So, if more than 50 species of fish live in the first, then about 40 in the second. The most suitable objects for fishing are bays, bays and lower reaches of rivers, where hunting for salmon, whitefish, cod and smelt families is possible. In addition, seals, sea hares and sometimes walruses can be found in the waters of the sea.
In the cold, rather long season, the Kara Sea is covered with ice, which forms in early autumn. The thickness of the ice in some places reaches up to 4 meters. Fast ice can be seen along the sea coast, and in the central part - floating ice.
In the warm season of the year, the ice is divided into lonely massifs. The bottom of the reservoir is covered primarily with sand and sandy silt, the gutters, as well as the basins, are gray, blue and brown silts.
Navigation in the Kara Sea is traditionally considered quite difficult.
Cities on the Kara Sea
(The port settlement of Dikson, the northernmost settlement in Russia)
An urban-type settlement and the only port on the Kara Sea - Dikson, was established in 2015. More than 500 people live in the village, there is unfavorable weather and a large number of tourists. Travelers here are attracted by the virtues of nature, a wide range of attractions, in particular, the local museum of local lore, the Polar Station and the fish factory. The unofficial name of the city is "Capital of the Arctic".
And the straits: the Red Army, Shokalsky and Vilkitsky. From the south, the border of the sea is the coast of the mainland. The Kara Sea is well open to the waters. The sea is located mainly on the continental shelf. These features make it possible to attribute the sea to the mainland types of marginal seas.
The Kara Sea is one of the largest seas in the Russian Federation. Its area is approximately 883 thousand km2. The volume of water reaches about 98 thousand km3. The average depth of the sea is 111 m, the maximum is 600 m. There are a large number of islands in the waters, most of which are small in size. Small islands are combined into archipelagos (Skerries, Minina) and are located along the coast of the mainland. Larger islands (Bely, Shokalsky, Vilkitsky, Sibiryakov, Russian) are located alone.
The coastline of the Kara Sea is uneven. The shores of Novaya Zemlya, which wash the waters of this sea, are indented by a large number of fjords. The mainland coast is also strongly dissected: in a number of places the sea sharply protrudes into the land, forming the Baidaratskaya and Obskaya bays. protrudes strongly into the sea. Along the coastline there are large bays (Gydansky, Yeniseisky and Pyasinsky), as well as a number of small bays.
The Kara Sea is characterized by a polar maritime climate, which is due to the northern location of the sea and its direct contact with the ocean. , located relatively close to the Kara Sea, softens.
But the island of Novaya Zemlya prevents the penetration of a large amount of warm air masses. The Kara Sea is in more severe climatic conditions than. Due to the large extent of the sea, climatic differences are observed in its different parts.
In autumn and winter it dominates the sea. At the beginning of the cold season, the direction of the wind depends on the position. In the northern part of the sea, there are predominantly, and in the southern part - winds of a changeable direction. The wind speed reaches 5 - 7 m/s. In winter, south, southwest and southeast winds prevail over most of the sea area. North winds dominate only in the north-east of the sea.
Storms most often occur in the western part of the sea. Near the island of Novaya Zemlya, wind constantly arises (Novaya Zemlya bora). The duration of this is small 2 - 3 hours, but in winter it can drag on for several days. South winds bring cold ones from the mainland. In March, on average, it reaches -28.6°C at Cape Chelyuskin and -20°C at Cape Zhelaniya. The lowest that can be at sea is - 45 - 50 ° С. In the western part of the sea, it sometimes brings warm masses of polar sea air. This cyclone moves from the west but deviates to the south as it collides with the mountains of Novaya Zemlya. Such intrusions of sea air most often occur in February. As a result, the weather in the western part of the sea in winter period fickle. In the northern and eastern parts of the sea, clear and cold prevails almost all the time.
Kara Sea. Gulf of Ob
IN spring time the sea is marked by winds of different directions. Their speed, as a rule, is 5 - 6 m / s. The cyclone stops. In a short time, the air warms up quickly enough. But still in spring the temperature does not exceed -7°C. In summer, an elevated area forms over the sea, which is why north winds begin to dominate here. Their speed is 4 - 5 m / s. During the warmest period (in July), the air warms up on average by 5–6 °С in the western part of the sea and by 1–2 °С in the east and northeast. Near the mainland coast, the air can warm up to +18 and +20 °С. But, despite the high summer temperatures, snow can fall at any summer time. In general, the short summer is marked by low temperatures and cloudy weather with a lot of rain.
A large amount carries its waters into the Kara Sea. In one year, this sea receives about 1290 km 3, which is approximately 55% of the total river flow to all seas located in the Siberian Arctic. Volume fresh water, which brings, is about 450 km3. brings about 600 km 3 of water, Plyasina - 80 km 3. River water enters the sea unevenly, depending on the season. In late summer - early autumn, rivers give 80% of all waste water. In winter only big rivers bring their water to the sea. The distribution of fresh water across the sea is not the same, every year it happens in different ways. River water can enter the western, eastern regions of the sea or be distributed in a fan-like manner. Almost 40% of the sea is under the influence of the river. Continental waters influence the climatic conditions of the Kara Sea. The water we give up from the rivers has more high temperature, how sea waters. It contributes to the weakening of the ice in the spring and prevents the waters from freezing in the fall. Also a large amount of continental water reduces the sea.
The rivers that flow into the Kara Sea have a relatively low level of pollution. However, the waters and the Yenisei have a high concentration of heavy metals, which adversely affects the ecosystem of the sea. Vessels have a negative impact on the ecological state of the sea. The places of their frequent movement are polluted with oil products. The waters belonging to the bays of the Kara Sea are characterized by specialists as moderately polluted.
