Location of the reservoir
If you look at dictionaries and reference books, you will find out that the sea is a part of the ocean separated by land or underwater terrain features. Following the above definition, we can say that the Laptev Sea is part of the Arctic Ocean. Almost all experts note that this is one of the most severe arctic seas. If the Barents and Kara Seas are under the influence of the warm ocean current Gulf Stream, then its influence does not reach these places. Long and harsh winter contributes to the formation of large volumes of sea ice.
Climate Features
The Laptev Sea is located at the same distance from both the Atlantic and Pacific Oceans. Warm air masses They practically do not penetrate into Arctic latitudes. Even in the southern part of the water area, negative temperatures persist for 9 months of the year. In the north, this period is even longer - almost 11 months. The average January temperature ranges from 25 to 35 degrees below zero. The absolute minimum temperature recorded here is 61 0 C. At the same time, clear, cloudless weather above the sea surface remains mostly clear. This fact is explained by the fact that the Siberian anticyclone dominates in these latitudes.
Coastline
The rivers flowing into the Laptev Sea: Anabar, Khatanga, Olenyok, Lena, Yana - carry in their waters a large volume of silt, pebbles, sand and boulders. Plus to this river waters significantly desalinate sea water at its confluence. Thus, at the mouth of the Lena, the salinity of the water is only 1%. While the average is 34%. At great depths, the seabed is covered with silt. This is explained by the fact that rivers regularly carry significant volumes of soil into the sea. River precipitation amounts to up to 25 centimeters per year. For this reason, coastal areas have relatively shallow depths: 20 - 50 meters.
Ice conditions
Unlike other bodies of water, the Laptev Sea is covered with ice for most of the year. Ice formation begins in September almost throughout the entire territory. In winter, fast ice up to two meters thick forms on the shallows in the eastern part. The ice begins to melt in June-July. And by August, a significant part of the water area is free of ice. During the warm period, so to speak, the edge of the ice changes its position under the influence of winds and currents. The Taimyr ice massif descends into the sea. It carries a large volume multi-year ice, which does not have time to melt during the short polar summer.
Vegetation and fauna
It is not difficult to guess that the temperature of the sea determines the qualitative composition of the plants and animals that live in its waters. Phytoplankton is represented in limited quantities seaweed and plants that are common in desalinated waters. Zoological plankton presented certain types ciliates, rotifers and other organisms that are food for Arctic fish species. These include whitefish, omul, char, nelma and sturgeon. Among the mammals that live here are walruses, seals and polar bears. Sea gulls nest near the coast.
Sea location
Laptev Sea (Yakut. Laptevtar baikallar) - marginal sea of the Arctic Ocean. Located between the Taimyr Peninsula and the Severnaya Zemlya Islands in the west and the New Siberian Islands in the east.
Physiographic location
The sea surface area is 672,000 km². The predominant depths are up to 50 m, the greatest depth is 3385 meters, average depth 540 meters. The banks are heavily indented. Large bays: Khatanga, Olenyoksky, Thaddeya, Yansky, Anabarsky, Maria Bay, Pronchishchevoy, Buor-Khaya. There are many islands in the western part of the sea, mostly off the coast. The islands of Komsomolskaya Pravda are located in the southwestern part of the sea.
Inhabitants and flowing rivers
The following rivers flow into the sea: Khatanga, Anabar, Olenyok, Lena, Yana. Some rivers form large deltas. The main port is Tiksi.
Walrus, bearded seal, and seal live here.
Bottom relief.
The bottom of the Laptev Sea is a gently sloping continental shelf that drops steeply to the ocean bed. The southern part of the sea is shallow, with depths of 20-50 meters. In shallow areas, the bottom is covered with sand and silt mixed with pebbles and boulders. River sediments accumulate at high speed near the coast, up to 20-25 centimeters per year. The continental slope is cut through by the Sadko Trench, which passes in the north into the Nansen Basin with depths of over 2 kilometers; the maximum depth of the Laptev Sea is also noted here - 3385 meters ( 79°35 N 124°40′ v.d.). At great depths the bottom is covered with silt.
Temperature and salinity
The salinity of sea water at the surface in the northwestern part of the sea is 28 ppm, in the southern part - up to 15 ppm, near river mouths - less than 10 ppm. The salinity of surface waters is strongly influenced by the flow of Siberian rivers and the melting of ice. With increasing depth, salinity increases rapidly, reaching 33 ppm
Sea water temperatures are low. In winter, under the ice, the water temperature is −0.8…-1.8 °C. Above a depth of 100 meters, the entire layer of water has negative temperatures (up to −1.8 °C). In summer, in ice-free areas of the sea, the most upper layer water can warm up to 4-6 °C, in bays up to 10 °C. In the deep sea zone at a depth of 250-300 meters there are relatively warm waters(up to 1.5 °C). Below this layer, the water temperature again becomes negative until the very bottom, where the temperature is about −0.8 °C.
To the number marginal seas Northern Arctic Ocean includes the Laptev Sea. It stretches between the Taimyr Peninsula, the Severnaya Zemlya Islands and the New Siberian Islands. The sea area has an area of about 672 thousand square meters. km. Maximum depth is almost 3390 m, and the average depth is 540 m. This sea got its name thanks to Russian explorers and navigators - Dmitry and Khariton Laptev. They did research north sea back in the 18th century. The Yakuts (indigenous people) call this body of water “Laptevtar”.
Features of the sea
A map of the Laptev Sea shows that its shores are heavily indented. The sea has large bays: Khatanga, Anabarsky, Yansky, Oleneksky, etc. There are many islands in its vast water area. They are concentrated mainly in its western part. The largest island groups: Thaddeus, Vilkitsky and Komsomolskaya Pravda. Single islands include Maly Taimyr, Peschany, Bolshoi Begichev, Starokadomskogo, etc.
The rugged coast of the Laptev Sea forms a variety of peninsulas, lips, capes, bays and bays. The following rivers carry their waters into this sea: Yana, Anabar, Khatanga, Olenek and Lena. They form vast deltas where they flow into the sea. Salinity sea water low.
Climatic conditions
The Laptev Sea is considered the harshest among the Arctic seas. The climate there is close to continental, but has pronounced polar and marine features. Continentality is expressed in significant fluctuations in annual temperature. The climate in different areas of the sea is heterogeneous. In autumn, winds form over the sea, which easily intensify into storms. In winter it is calm and partly cloudy. Rare cyclones occur, causing cold and strong winds.
Use of the Laptev Sea
The sea is located far from the center of the country, in a harsh climate. Therefore, its economic use is difficult. For the Russian economy, the Laptev Sea has great importance, since in this area cargo is transported along the northern sea route. Here the transit of goods takes place and their delivery to the port of Tiksi. Local residents are engaged in fishing. The density of indigenous people is very low. Evenks, Yukaghirs and other nationalities live on the banks. The Laptev Sea is the venue for various scientific research. Scientists study how water circulates, monitor ice balance, and make hydrometeorological forecasts.
This sea has the status of a continental marginal sea.
There are about several dozen islands in the waters of the Laptev Sea. Most of them are located in the western zone of the sea. Here the islands are located both in small groups and individually. Here are the following groups of skeletons: Komsomolskaya Pravda, Vilkitsky and Thaddeus. Among the single skeletons, the largest are: Starokadomsky, Maly Taimyr, Bolshoy Begichev, Peschany, Stolbovoy and Belkovsky. A large number of small islands are located in river deltas.
The sea coastline is quite uneven, there is a large number of bays, bays, and capes. The eastern shores of the Severnaya Zemlya islands and the Taimyr Peninsula are heavily indented. To the east of it there are large bays: Khatanga, Anabarsky, Oleneksky and Yansky. There are also bays (Kozhevnikova, Nordvik, Tiksi), bays (Vankina and Buor-Khaya) and peninsulas (Khara-Tumus, Nordvik). The shores washed by the Laptev Sea have different... Some shores have low mountains, some are lowlands.
The Laptev Sea is located in the shelf zone, the continental slope, and occupies a small area of the ocean floor. Due to this location, it ends abruptly in the north. On this plain there are several hills and banks. There is a short trench opposite the mouth. A narrow and fairly long trench extends from Stolbovoy Island to the north. Another trench is located near Oleneksky Bay. In the east of the Laptev Sea there are two banks, Semenovskaya and Vasilievskaya.
Most of the sea is shallow. The shallowest part is located in the south of the sea. Half of the sea has a depth of up to 50 m. When moving north, the depth of the sea increases. First there are minor changes in depth (from 50 m to 100), and then the depth increases sharply from 2000 m or more.
The climatic conditions of the Laptev Sea are quite harsh compared to other seas. This is due to the location of the sea near, the distance from the waters and the neighboring location of the mainland. The climatic conditions of the sea are close to continental ones. Although there are also features of the sea. In the Laptev Sea, such a continental climate feature can be traced as a strong change in air temperature throughout the year. But under the influence of the sea this fluctuation is not as clearly expressed as on land.
IN different time different centers influence the climate of the sea each year. During the cold period, the sea is predominantly dominated by a high area. In autumn, the winds of alternating direction give way to southern ones, and their strength increases to gale force.
In winter, three zones can be distinguished at sea, which have slightly different climatic conditions. The southeastern part of the sea is dominated by the Siberian Sea. In the north, the influence of the Polar Maximum is felt. The western part is periodically affected by the Icelandic low. The Siberian Anticyclone has the greatest impact on the expanses of the Laptev Sea. Thus, in winter, southern and southwestern winds blow predominantly, the speed of which is about 8 m/s. At the end of winter, their strength weakens and calms are observed. During this period, a strong cooling is noticeable. in January it drops to – 26 – 29°C. In general, the weather in winter is cloudless and calm. Sometimes formed south of the sea, contribute to the emergence of powerful northern ones. Such storms continue for several days and then cease.
During the warm period the region high pressure replaced by a low depression. Spring winds do not have a constant direction. Along with the southern winds, there are also northern ones. Such winds are usually gusty and not strong. The air temperature is constantly increasing. But the weather is still quite cold. IN summer time Northern winds predominate, the speed of which does not exceed 3 - 4 m/s. Powerful winds are not typical for summer. At this time it rises and reaches its highest point in August +1-5°C. In enclosed spaces, the air temperature can be significantly higher. For example, in Tiksi Bay the temperature was recorded at +32.5°C. Summer is very often dominated by cyclones, making it cloudy and rainy.
Fishing and hunting of sea animals is poorly developed; marine fishing is mainly carried out near river mouths. The Laptev Sea has economic importance, since transportation is carried out here. The port of Tisci is of great importance in the departure and delivery of goods.
The coastal waters of the Laptev Sea contain a high concentration of phenol, which comes along with the waters. Great content phenol in river and coastal waters is due to the huge number of sunken trees. The most polluted waters are the Neelov Bay. The water spaces of Tiksi and Buor-Khaya bays are polluted. Ecological standing water resources Bulunkan Bay is marked as catastrophic. The content of large amounts of toxic substances in coastal waters is due to the discharge of untreated water from Tiksi. The sea also contains a large amount of petroleum products in areas of developed shipping.
LAPTEV SEA, a marginal sea of the Arctic Ocean, off the northeastern coast of Asia, between the Severnaya Zemlya archipelago, the Taimyr Peninsula, the coast of Siberia and the New Siberian Islands. It communicates through the straits with the seas: in the west with the Kara, in the east with the East Siberian. Western border runs from Cape Arktichesky (the northern point of Komsomolets Island) along the eastern shores of the islands of the Severnaya Zemlya archipelago and the Red Army, Shokalsky, Vilkitsky straits, then along the eastern coasts of the Taimyr Peninsula to the mouth of Khatanga; southern - further along the mainland coast to Cape Svyatoy Nos (141° east longitude); eastern - along the Dmitry Laptev Strait, the western shore of Bolshoi Lyakhovsky Island, Eterikan Strait, west bank Maly Lyakhovsky Island, Sannikov Strait, west coast Kotelny Island to Cape Anisiy, then in the open sea along the meridian of 139° east longitude to the parallel of 79° north latitude; northern - from this point along an arc great circle to Cape Arctic. Within these boundaries, the area of the Laptev Sea is 662 thousand km 2, the volume is 353 thousand km 3. The greatest depth is 3385 m (79°35'N, 124°40'E).
The heavily indented shores of the Laptev Sea form many bays, bays, and peninsulas. Large bays - Khatanga, Anabarsky, Olenyoksky, Yansky, Faddeya; bays - Pronchishchevoy, Kozhevnikova, Nordvik, Tiksi; lips - Buor-Khaya, Vankina, Sellyakhskaya, Ebelyakhskaya; peninsulas - Khara-Tumus, Nordvik, Shirokostan. There are several dozen islands (mostly small) located off the western and southern coasts; the largest islands are Bolshoy Begichev, Maly Taimyr, Starokadomskogo, Belkovsky, Stolbovoy; group of islands - Thaddeus, Komsomolskaya Pravda, Petra, Danube. Many small islands are located in the mouths and deltas of rivers. The nature of the coasts is varied, abrasion and accumulative predominate; large sections of the coasts are composed of fossil ice and are subject to intense erosion; Thus, the islands of Vasilievsky and Semenovsky, discovered in 1815, were completely washed away and by the mid-1950s they turned into sand banks with the same names. The coasts are mostly low-lying, but in some areas low mountains come close to the coastline.
Relief and geological structure bottom. The bottom of the Laptev Sea is represented by a plain weakly dissected by several troughs, gently sloping from south to north. The sea is shallow, about half of the bottom is at depths less than 50 m, the shelf (along the isobath of 200 m) occupies 72%. The continental slope is cut through by the deep-sea Sadko Trench, which to the north turns into the Nansen Basin. Areas with depths of more than 2000 m (northwestern part of the sea) account for only 13%. The large, shallow part of the Laptev Sea is located in the area of the junction of the Taimyr, Verkhoyansk-Kolyma and Novosibirsk-Chukchi fold systems, the Mesozoic complexes of which are dissected by a branched Cenozoic rift system of northwest strike and covered by a cover of Upper Cretaceous - Cenozoic sediments with a thickness of 1-1.5 km per uplifts up to 8-12 km in troughs. In the northern, deep-sea part of the sea, the sedimentary cover rests on igneous rocks of the oceanic crust. Modern bottom sediments on the shelf are represented by sands, silty silts, sometimes with inclusions of pebbles and boulders; in deep-sea areas, predominantly silty-clayey and clayey silts are observed at the bottom. Sedimentation in coastal areas is significantly influenced by solid river runoff. Lena and Yana alone annually bring up to 17.5 million tons of suspended sediment to the southeastern part of the sea. The eastern part of the Laptev Sea is seismically active (earthquakes with a magnitude of up to 6 occur); increased seismicity of the coast is noted.
Climate. The climate is Arctic marine, with features of continental in the southern coastal areas; high-latitude position, proximity to the mainland, isolation from the moderating influence of the Atlantic and Pacific Oceans determine its severity. The polar night lasts from three to five months. For most of the year, the sea is under the influence of the Siberian High, which causes weak cyclonic activity and the monsoon nature of the wind situation. IN winter time Southern and southwestern winds prevail at a speed of 8-10 m/s, the air becomes very cold, the temperature in January drops to -34 °C, the absolute minimum was -61 °C. Mostly in summer north winds(speed 3-4 m/s), air temperature in July from 0 °C on the northern borders to 4 °C on the southern coasts. In small bays well protected from the wind, the air warms up to 12-15 °C in summer, maximum temperatures in summer reach 22-24 °C, minimum temperatures drop to -4 °C.
Hydrological regime. Many small and several large rivers flow into the Laptev Sea, so fresh runoff has a noticeable impact on the hydrological regime of the shallow sea. One of largest rivers basin of the Arctic Ocean - Lena annually brings 520 km 3 of water, Khatanga - 105 km 3, Olenyok - 38 km 3, Yana - 31.5 km 3. In total, over 700 km 3 enters the Laptev Sea annually fresh water, or over 30% of the river flow of the Arctic basin. The flow is unevenly distributed across the seasons: in January, about 36 km 3 (over 5% of the annual value) flows into the sea, and in August up to 290 km 3 (over 40%) of water flows into the sea. In coastal areas with a strong influence of river runoff, highly desalinated water is formed in the surface layer in summer, when in the Lena estuary the salinity drops to 10‰. Salinity increases towards the north and northwest, reaching 31‰ at the Arctic Cape. The surface water temperature at this time varies from 4 to -1 °C. In winter, salinity everywhere increases noticeably due to a decrease in fresh runoff and salinization of the surface layer during the process of ice formation: in the Tiksi area up to 15‰, near the Arctic Cape up to 33‰. The surface water temperature in winter is everywhere close to the freezing point and is determined by the salinity of the water, varying accordingly from -1 to -1.8 °C. With depth, the temperature quickly decreases and deeper than 15-20 m, even in summer it takes negative values everywhere. Only in deep-sea areas, in a layer of 100-300 m, is the water temperature above 0 ° C due to the warming influence of intermediate Atlantic waters.
Most of the year the sea is covered with ice. The ice-forming season lasts from 7-8 months in the south to 9-11 months in the north. In cold years, ice can form in all seasons; in very warm years, at the end of August - beginning of September, the sea is completely free of ice. Vast coastal areas, especially in the southeastern part, are covered with stationary fast ice in winter.
Typically, the width of the fast ice strip is determined by an isobath of 25 m, so in the Laptev Sea fast ice can occupy up to 30% of the water area. On the rest of the sea the ice is drifting. By the end of winter, fast ice and drifting ice can (in one season) grow in thickness up to 1.8-2.0 m. The concentration of drifting ice strongly depends on the prevailing winds. Steady eastern winds often drive away drifting ice from fast ice, creating even in the most very coldy space open water- the so-called sealed wormwood. This phenomenon in the past was called the Great Siberian Polynya. With the cessation of the eastern winds, the polynya is quickly covered with young ice.
Due to weak winds in summer and high ice concentration in winter, wind mixing is poorly developed and usually does not penetrate deeper than 8-10 m. Autumn-winter cooling and ice formation contribute to the development of convective mixing, which in shallow southern areas penetrates to the bottom by the end of winter, and in northern ones - to a depth of 90-100 m. The horizontal circulation is mainly cyclonic in nature. Along the mainland coast the flow moves from west to east. Near the New Siberian Islands most of The flow goes north in the form of the Novosibirsk Current, where it splits into two branches: one turns east, into the East Siberian Sea, the other goes west. Near Severnaya Zemlya, the current deviates to the south and, under the name of the East Taimyr Current, closes the cycle.
The tides are of an irregular semi-diurnal nature, the height is 0.3-0.8 m. Only at the top of the funnel of the Khatanga Bay during syzygy does the tide exceed 2 m. Up the Khatanga tidal wave penetrates 200-300 km. Surge level fluctuations usually do not exceed 2.0-2.5 m. Seasonal level fluctuations are small, observed mainly only in the south-eastern regions, where they reach 0.4 m (the minimum level is observed in winter, the maximum in summer). The prevailing waves are 2-4 points with a wave height of about 1 m. In the central part of the sea during autumn storms with a force of 5-7 points, the wave height reaches 4-5 m, their maximum height 6 m.
History of the study. The Laptev Sea has been known to Russian explorers since the 1st half of the 17th century. Traces of a Pomeranian artel found on the shores of the Taimyr Peninsula indicate that the Russians entered the Laptev Sea no later than 1620. In 1633-34, explorers Ilya Perfilyev and I.I. Rebrov, going down the Lena, discovered Olenyok Bay, the mouth of the Olenyok River, Yansky Bay, and the mouth of the Yana River. The first surveys of the shores of the Laptev Sea from the mouth of the Lena to the northern shores of Taimyr were carried out in 1735-36 by Lieutenant V.V. Pronchishchev. The previous names of the sea were Siberian, from the end of the 19th century - Nordenskiöld, established in 1935 modern name in honor of naval officers, participants of the 2nd Kamchatka expedition V. I. Bering, cousins D. Ya. Lapteva and Kh. P. Lapteva, who completed filming of its continental coasts and compiled the first reliable map of this area. The New Siberian Islands were discovered by Siberian hunters in 1712-1812. The first reliable maps of the islands were compiled by the government expedition of Lieutenant P. F. Anjou in 1821-23. The Severnaya Zemlya archipelago was discovered in 1913 by a hydrographic expedition of the Arctic Ocean, led by Senior Lieutenant B.A. Vilkitsky. A map of the coasts of Severnaya Zemlya was compiled by the expedition of G. A. Ushakov in 1930-32.
Economic use. The Laptev Sea is characterized as an area of low economic use. Fishing is of local importance. Among the commercial species are Arctic char, Siberian whitefish, omul, nelma, sturgeon, vendace, and muksun. Mammals are represented by walruses, seals, and beluga whales. Polar bears breed on the islands. On the banks there are white arctic fox and lemmings. The world of birds is diverse, especially in bird colonies, where guillemots and guillemots nest; numerous species of gulls and skuas; common polar owl, etc.
The Laptev Sea is part of the Northern Sea Route. The main port is Tiksi, where cargo is transshipped between river and sea. Cargo transportation is dominated by timber, building materials, furs, and food products. Sea freight transportation is carried out under icebreaker assistance. The Laptev Sea is promising in terms of oil and gas content, but its development is difficult due to harsh natural conditions.
Ecological situation. In general, the ecological situation in the Laptev Sea is characterized as favorable due to weak economic use this area. The shallow parts of the sea are slightly polluted, resulting in eutrophication of bays, gulfs, and coastal areas of the sea; a decrease in the size of aquatic organisms is observed.
Lit.: Dobrovolsky A.D., Zalogin B.S. Seas of the USSR. M., 1982; Atlas of the Arctic. M., 1985; Tectonic map of the Kara and Laptev seas and northern Siberia / Edited by N. A. Bogdanov, V. E. Khain. M., 1998; Zalogin B.S., Kosarev A.N. Seas. M., 1999; Geoecology of the shelf and coasts of the seas of Russia / Edited by N. A. Aibulatov. M., 2001.
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