Facts about the Sea of ​​Okhotsk. Physiographic conditions of the Sea of ​​Okhotsk

The Sea of ​​Okhotsk protrudes quite deeply into the land and extends noticeably from southwest to northeast. It has shorelines almost everywhere. It is separated from the Sea of ​​Japan by about. Sakhalin and the conventional lines of Cape Sushchev - Cape Tyk (Nevelskoy Strait), and in the La Perouse Strait - Cape Soya - Cape Crillon. The southeastern border of the sea goes from Cape Nosappu (Hokkaido Island) and through the Kuril Islands to Cape Lopatka (Kamchatka Peninsula).

The Sea of ​​Okhotsk is one of the largest and deep seas peace. Its area is 1,603 thousand km 2, volume - 1,316 thousand km 3, average depth- 821 m, greatest depth - 3,521 m.

The Sea of ​​Okhotsk belongs to the marginal seas of the mixed continental-ocean type. From Pacific Ocean it is separated by the Kuril ridge, numbering about 30 large and many small islands and rocks. The Kuril Islands are located in a belt of seismic activity, which includes more than 30 active and 70 extinct volcanoes. Seismic activity occurs on the islands and underwater. In the latter case, tsunami waves are often formed. In the sea there is a group of Shantarsky islands, the Spafaryev, Zavyalov, Yamsky islands and the small island of Jonah - the only one of all that is remote from the coast. Although the coastline is long, it is relatively weakly indented. At the same time, it forms several large bays (Aniva, Terpeniya, Sakhalinsky, Akademii, Tugursky, Ayan, Shelikhova) and bays (Udskaya, Tauyskaya, Gizhiginskaya and Penzhinskaya).

The Nevelskoy and La Perouse straits are relatively narrow and shallow. The width of the Nevelskoy Strait (between capes Lazarev and Pogibi) is only about 7 km. The width of the La Perouse Strait is 43-186 km, depth is 53-118 m.

The total width of the Kuril Straits is about 500 km, and the maximum depth of the deepest of them, the Bussol Strait, exceeds 2300 m. Thus, the possibility of water exchange between the Seas of Japan and the Sea of ​​Okhotsk is incomparably less than between the Sea of ​​Okhotsk and the Pacific Ocean.

However, even the depth of the deepest of the Kuril Straits is significantly less than the maximum depth of the sea, and therefore the Kuril ridge is a huge threshold that fences off the sea depression from the ocean.

The most important for water exchange with the ocean are the Bussol and Krusenstern straits, since they have the largest area and depth. The depth of the Bussol Strait was indicated above, and the depth of the Kruzenshtern Strait is 1920 m. Of less importance are the Frieza, Fourth Kurilsky, Ricord and Nadezhda straits, whose depths are more than 500 m. The depths of the remaining straits generally do not exceed 200 m, and their areas are insignificant.

On distant shores

The shores of the Sea of ​​Okhotsk in different areas belong to different geomorphological types. For the most part, these are abrasive shores modified by the sea, and only in Kamchatka and Sakhalin are there accumulative shores. The sea is mostly surrounded by high and steep shores. In the north and northwest, rocky ledges descend directly to the sea. Along the Sakhalin Bay the shores are low. The southeastern coast of Sakhalin is low, and the northeastern coast is low. The shores of the Kuril Islands are very steep. The northeastern coast of Hokkaido is predominantly low-lying. The coast of the southern part of Western Kamchatka has the same character, but the shores of its northern part rise somewhat.

Shores of the Sea of ​​Okhotsk

Bottom relief

The bottom topography of the Sea of ​​Okhotsk is varied. The northern part of the sea is a continental shelf - an underwater continuation of the Asian continent. The width of the continental shelf in the area of ​​the Ayano-Okhotsk coast is approximately 185 km, in the area of ​​Udskaya Bay - 260 km. Between the meridians of Okhotsk and Magadan, the width of the shoal increases to 370 km. WITH western edge In the basin of the sea there is an island sandbank of Sakhalin, and on the eastern side there is a sandbank of Kamchatka. The shelf occupies about 22% of the bottom area. The rest, most (about 70%) of the sea is located within the continental slope (from 200 to 1500 m), on which individual underwater hills, depressions and trenches are distinguished.

The deepest, southern part of the sea (more than 2500 m), which is a section of the bed, occupies 8% total area seas. It stretches as a strip along the Kuril Islands and gradually narrows from 200 km against the island. Iturup up to 80 km against the Krusenstern Strait. Great depths and significant bottom slopes distinguish the southwestern part of the sea from the northeastern part, which lies on the continental shallows.

Of the large elements of the bottom relief of the central part of the sea, two underwater hills stand out - the Academy of Sciences and the Institute of Oceanology. Together with the protrusion of the continental slope, they divide the sea basin into three basins: the northeastern - TINRO depression, the northwestern - Deryugin depression and the southern deep-sea - Kuril depression. The depressions are connected by gutters: Makarov, P. Schmidt and Lebed. To the northeast of the TINRO depression, the Shelikhov Bay trench extends.

The deepest depression is TINRO, located west of Kamchatka. Its bottom is a plain lying at a depth of about 850 m, with a maximum depth of 990 m.

The Deryugin Depression is located east of the underwater base of Sakhalin. Its bottom is a flat plain, raised at the edges, lying on average at a depth of 1700 m, the maximum depth of the depression is 1744 m.

The Kuril Depression is the deepest. This is a huge flat plain lying at a depth of about 3300 m. Its width in the western part is approximately 212 km, and its length in the northeast direction is about 870 km.

Bottom topography and currents of the Sea of ​​Okhotsk

Currents

Under the influence of winds and the influx of water through the Kuril Straits, character traits systems of non-periodic currents in the Sea of ​​Okhotsk. The main one is a cyclonic system of currents, covering almost the entire sea. It is caused by the predominance of cyclonic atmospheric circulation over the sea and the adjacent part of the Pacific Ocean. In addition, stable anticyclonic gyres can be traced in the sea: to the west of the southern tip of Kamchatka (approximately between 50-52° N and 155-156° E); above the TINRO depression (55-57° N and 150-154° E); in the area of ​​the Southern Basin (45-47° N and 144-148° E). In addition, a vast area of ​​cyclonic water circulation is observed in the central part of the sea (47-53° N and 144-154° E), and the cyclonic circulation is to the east and northeast of the northern tip of the island. Sakhalin (54-56° N and 143-149° E).

Strong currents move around the sea along the coastline counterclockwise: the warm Kamchatka Current, directed north into Shelikhov Bay; flow of a western and then southwestern direction along the northern and northwestern shores of the sea; the stable East Sakhalin Current going south, and the rather strong Soya Current entering the Sea of ​​Okhotsk through the La Perouse Strait.

On the southeastern periphery of the cyclonic circulation of the central part of the sea, a branch of the Northeast Current is distinguished, opposite in direction to the Kuril Current in the Pacific Ocean. As a result of the existence of these flows, stable areas of convergence of currents are formed in some of the Kuril straits, which leads to lowering of waters and has a significant impact on the distribution of oceanological characteristics not only in the straits, but also in the sea itself. And finally, another feature of the circulation of the waters of the Sea of ​​​​Okhotsk is two-way stable currents in most of the Kuril Straits.

Surface currents on the surface of the Sea of ​​Okhotsk are most intense off the western coast of Kamchatka (11-20 cm/s), in the Sakhalin Gulf (30-45 cm/s), in the Kuril Straits (15-40 cm/s), over the Southern Basin ( 11-20 cm/s) and during the Soya (up to 50-90 cm/s). In the central part of the cyclonic region, the intensity of horizontal transport is much less than at its periphery. In the central part of the sea, velocities vary from 2 to 10 cm/s, with the predominant velocities being less than 5 cm/s. A similar picture is observed in Shelikhov Bay: fairly strong currents off the coast (up to 20-30 cm/s) and low speeds in the central part of the cyclonic gyre.

In the Sea of ​​Okhotsk are well expressed different kinds periodic tidal currents: semidiurnal, diurnal and mixed with a predominance of semidiurnal or diurnal components. Tidal current speeds range from a few centimeters to 4 m/s. Far from the coast, current speeds are low - 5-10 cm/s. In straits, bays and off the coast, their speeds increase significantly. For example, in the Kuril Straits, current speeds reach 2-4 m/s.

The tides of the Sea of ​​Okhotsk have a very complex nature. The tidal wave enters from the south and southeast from the Pacific Ocean. The semidiurnal wave moves north, and at the 50° parallel it divides into two parts: the western one turns northwest, and the eastern one moves toward Shelikhov Bay. The daily wave also moves north, but at the latitude of the northern tip of Sakhalin it is divided into two parts: one enters Shelikhov Bay, the other reaches the northwestern coast.

Diurnal tides are the most widespread in the Sea of ​​Okhotsk. They are developed in the Amur Estuary, Sakhalin Bay, on the coast of the Kuril Islands, off the western coast of Kamchatka and in the Gulf of Penzhina. Mixed tides are observed on the northern and northwestern coasts of the sea and in the area of ​​the Shantar Islands.

The highest tides (up to 13 m) were recorded in Penzhinskaya Bay (Cape Astronomichesky). In the area of ​​the Shantar Islands, the tide exceeds 7 m. The tides are significant in the Sakhalin Bay and in the Kuril Straits. In the northern part of the sea their size reaches 5 m.

Fur seal rookery

The lowest tides were observed off the eastern coast of Sakhalin, in the area of ​​the La Perouse Strait. In the southern part of the sea, the tides are 0.8-2.5 m.

In general, tidal level fluctuations in the Sea of ​​Okhotsk are very significant and have a significant impact on its hydrological regime, especially in the coastal zone.

In addition to tidal fluctuations, surge level fluctuations are also well developed here. They occur mainly when deep cyclones pass over the sea. Surge increases in level reach 1.5-2 m. The largest surges are noted on the coast of Kamchatka and in Terpeniya Bay.

The considerable size and great depths of the Sea of ​​Okhotsk, frequent and strong winds above it determine the development of large waves here. The sea is especially rough in the fall, and in ice-free areas even in winter. These seasons account for 55-70% of storm waves, including those with wave heights of 4-6 m, and the highest wave heights reach 10-11 m. The most turbulent are the southern and south-eastern regions of the sea, where the average frequency of storm waves is 35 -40%, and in the northwestern part it decreases to 25-30%. When the waves are strong, a crowd forms in the straits between the Shantar Islands.

Climate

The Sea of ​​Okhotsk is located in the zone monsoon climate temperate latitudes. A significant part of the sea in the west extends deep into the mainland and lies relatively close to the cold pole of the Asian landmass, so the main source of cold for the Sea of ​​Okhotsk is located to the west of it. The relatively high ridges of Kamchatka make it difficult for warm Pacific air to penetrate. Only in the southeast and south is the sea open to the Pacific Ocean and the Sea of ​​Japan, from where a significant amount of heat enters it. However, the influence of cooling factors is stronger than warming ones, so the Sea of ​​Okhotsk is generally cold. At the same time, due to the large meridional extent, significant differences in synoptic conditions and meteorological conditions arise here. In the cold part of the year (from October to April), the sea is affected by the Siberian Anticyclone and the Aleutian Low. The influence of the latter extends mainly to the southeastern part of the sea. This distribution of large-scale pressure systems causes strong, sustained northwest and northerly winds, often reaching gale force. Little wind and calm are almost completely absent, especially in January and February. In winter, the wind speed is usually 10-11 m/s.

The dry and cold Asian winter monsoon significantly cools the air over the northern and northwestern regions of the sea. In the coldest month - January - average temperature air in the northwest of the sea is –20 - 25°, in central regions–10–15°, and in the southeastern part of the sea it is –5–6°.

In the autumn winter time Cyclones of predominantly continental origin enter the sea. They bring with them increased wind, sometimes a decrease in air temperature, but the weather remains clear and dry, as continental air arrives from the cooled mainland. In March - April, a restructuring of large-scale pressure fields occurs. The Siberian anticyclone is collapsing, and the Hawaiian high is intensifying. As a result, during the warm season (from May to October), the Sea of ​​Okhotsk is influenced by the Hawaiian High and the low pressure area located over Eastern Siberia. At this time, weak south-easterly winds prevail over the sea. Their speed usually does not exceed 6-7 m/s. These winds are most common in June and July, although stronger northwest and northerly winds are sometimes observed during these months. In general, the Pacific (summer) monsoon is weaker than the Asian (winter) monsoon, since in the warm season the horizontal pressure gradients are smoothed out.

In summer, the average monthly air temperature in August decreases from the southwest (from 18°) to the northeast (to 10-10.5°).

In the warm season above southern part seas pass quite often tropical cyclones- typhoons. They are associated with increased winds to storm force, which can last up to 5-8 days. The predominance of south-eastern winds in the spring-summer season leads to significant cloudiness, precipitation, and fog.

Monsoon winds and stronger winter cooling of the western part of the Sea of ​​Okhotsk compared to the eastern part are important climatic features of this sea.

Quite a lot of mostly small rivers flow into the Sea of ​​Okhotsk, therefore, despite the significant volume of its waters, the continental flow is relatively small. It is approximately 600 km 3 /year, with about 65% of the flow coming from the Amur. Other relatively large rivers - Penzhina, Okhota, Uda, Bolshaya (in Kamchatka) - bring significantly less to the sea fresh water. Runoff occurs mainly in spring and early summer. At this time, its greatest influence is felt mainly in the coastal zone, near the mouths of large rivers.

Hydrology and water circulation

Geographical location, large length along the meridian, monsoon wind changes and good communication between the sea and the Pacific Ocean through the Kuril Straits are the main natural factors that most significantly influence the formation of the hydrological conditions of the Sea of ​​Okhotsk. The amounts of heat inflow and outflow into the sea are determined mainly by the rational heating and cooling of the sea. The heat brought by Pacific waters is of subordinate importance. However, for the water balance of the sea, the arrival and flow of water through the Kuril Straits plays a decisive role.

The flow of surface Pacific waters into the Sea of ​​Okhotsk occurs mainly through the northern straits, in particular through the First Kuril Strait. In the straits of the middle part of the ridge, both the influx of Pacific waters and the outflow of Okhotsk waters are observed. Thus, in the surface layers of the Third and Fourth Straits, apparently, there is a flow of water from the Sea of ​​Okhotsk, in the bottom layers there is an influx, and in the Bussol Strait it’s the other way around: in the surface layers there is an influx, in the deep layers there is a runoff. In the southern part of the ridge, mainly through the Ekaterina and Frieze straits, water predominantly drains from the Sea of ​​Okhotsk. The intensity of water exchange through the straits can vary significantly.

In the upper layers of the southern part of the Kuril ridge, the flow of Sea of ​​Okhotsk waters predominates, and in the upper layers of the northern part of the ridge, the influx of Pacific waters occurs. In the deep layers, the influx of Pacific waters predominates.

Water temperature and salinity

The influx of Pacific waters significantly affects the distribution of temperature, salinity, formation of structure and general circulation waters of the Sea of ​​Okhotsk. It is characterized by a subarctic water structure, in which cold and warm intermediate layers are well defined in summer. A more detailed study of the subarctic structure in this sea showed that there are Sea of ​​Okhotsk, Pacific and Kuril varieties of the subarctic water structure. Although they have the same vertical structure, they have quantitative differences in the characteristics of water masses.

The following water masses are distinguished in the Sea of ​​Okhotsk:

surface water mass that has spring, summer and autumn modifications. It is a thin heated layer 15-30 m thick, which limits the upper maximum of stability, determined mainly by temperature. This water mass is characterized by temperature and salinity values ​​corresponding to each season;

The Sea of ​​Okhotsk water mass is formed in winter from surface water and in spring, summer and autumn appears in the form of a cold intermediate layer lying between horizons of 40-150 m. This water mass is characterized by a fairly uniform salinity (31-32.9‰) and varying temperatures. In most of the sea its temperature is below 0° and reaches -1.7°, and in the area of ​​the Kuril Straits it is above 1°;

The intermediate water mass is formed mainly due to the descent of water along underwater slopes, within the sea, ranging from 100-150 to 400-700 m, and is characterized by a temperature of 1.5° and a salinity of 33.7‰. This water mass is distributed almost everywhere, except for the northern part of the sea, Shelikhov Bay and some areas along the coast of Sakhalin, where the Sea of ​​Okhotsk water mass reaches the bottom. The thickness of the layer of intermediate water mass decreases from south to north;

The deep Pacific water mass is the water of the lower part of the warm layer of the Pacific Ocean, entering the Sea of ​​Okhotsk at horizons below 800-1000 m, i.e. below the depth of the waters descending in the straits, and in the sea it appears in the form of a warm intermediate layer. This water mass is located at horizons of 600-1350 m, has a temperature of 2.3° and a salinity of 34.3‰. However, its characteristics change in space. The highest values ​​of temperature and salinity are observed in the northeastern and partly in the northwestern regions, which is associated here with rising waters, and the lowest values ​​of the characteristics are characteristic of the western and southern regions where the waters descend.

The water mass of the southern basin is of Pacific origin and represents the deep water of the northwestern part of the Pacific Ocean near the horizon of 2300 m, i.e. horizon corresponding to the maximum depth of the threshold in the Kuril Straits, located in the Bussol Strait. This water mass fills the basin from a horizon of 1350 m to the bottom and is characterized by a temperature of 1.85° and a salinity of 34.7‰, which vary only slightly with depth.

Among the identified water masses, the Sea of ​​Okhotsk and the deep Pacific are the main ones; they differ from each other not only in thermohaline, but also in hydrochemical and biological parameters.

The water temperature at the sea surface decreases from south to north. In winter, almost everywhere the surface layers are cooled to a freezing temperature of –1.5-1.8°. Only in the southeastern part of the sea does it remain around 0°, and near the northern Kuril Straits, under the influence of Pacific waters, the water temperature reaches 1-2°.

Spring warming at the beginning of the season mainly leads to the melting of ice, only towards the end of it does the water temperature begin to rise.

In summer, the distribution of water temperature on the sea surface is quite varied. In August, the waters adjacent to the island are warmest (up to 18-19°). Hokkaido. In the central regions of the sea, the water temperature is 11-12°. The coldest surface waters are observed near the island. Iona, near Cape Pyagin and near the Krusenstern Strait. In these areas, the water temperature is between 6-7°. The formation of local centers of increased and decreased water temperatures on the surface is mainly associated with the redistribution of heat by currents.

The vertical distribution of water temperature varies from season to season and from place to place. In the cold season, temperature changes with depth are less complex and varied than in warm seasons.

In winter, in the northern and central regions of the sea, water cooling extends to horizons of 500-600 m. The water temperature is relatively uniform and varies from -1.5-1.7° on the surface to -0.25° at horizons of 500-600 m, deeper rises to 1-0°, in the southern part of the sea and near the Kuril Straits the water temperature from 2.5-3° on the surface drops to 1-1.4° at horizons of 300-400 m and then gradually rises to 1.9-2 .4° in the bottom layer.

In summer, surface waters are heated to a temperature of 10-12°. In the subsurface layers, the water temperature is slightly lower than on the surface. A sharp drop in temperature to -1 - 1.2° is observed between horizons of 50-75 m, deeper, to horizons of 150-200 m, the temperature quickly rises to 0.5 - 1°, and then it rises more smoothly, and at horizons of 200 - 250 m is equal to 1.5 - 2°. Further, the water temperature remains almost unchanged until the bottom. In the south and southeastern parts sea, along the Kuril Islands, water temperature from 10 - 14° on the surface drops to 3 - 8° at a horizon of 25 m, then to 1.6-2.4° at a horizon of 100 m and to 1.4-2° at the bottom . The vertical temperature distribution in summer is characterized by a cold intermediate layer. In the northern and central regions of the sea the temperature is negative, and only near the Kuril Straits it has positive values. In different areas of the sea, the depth of the cold intermediate layer is different and varies from year to year.

The distribution of salinity in the Sea of ​​Okhotsk varies relatively little between seasons. Salinity increases in the eastern part, which is under the influence of Pacific waters, and decreases in the western part, desalinated by continental runoff. In the western part, salinity on the surface is 28-31‰, and in the eastern part - 31-32‰ and more (up to 33‰ near the Kuril ridge),

In the northwestern part of the sea, due to desalination, the salinity on the surface is 25‰ or less, and the thickness of the desalinated layer is about 30-40 m.

Salinity increases with depth in the Sea of ​​Okhotsk. At horizons of 300-400 m in the western part of the sea, salinity is 33.5‰, and in the eastern part it is about 33.8‰. At a horizon of 100 m, salinity is 34‰ and then towards the bottom it increases slightly, by only 0.5-0.6‰.

In individual bays and straits, the salinity value and its stratification may differ significantly from the waters open sea depending on local conditions.

In accordance with temperature and salinity, denser waters are observed in winter in the northern and central areas of the sea, covered with ice. The density is somewhat lower in the relatively warm Kuril region. In summer, the density of water decreases, its lowest values ​​are confined to zones of influence of coastal runoff, and the highest are observed in areas of distribution of Pacific waters. In winter, it rises slightly from the surface to the bottom. In summer, its distribution depends on temperature in the upper layers, and on salinity in the middle and lower layers. In summer, a noticeable density stratification of waters is created vertically, the density increases especially noticeably at horizons of 25-50 m, which is associated with the heating of waters in open areas and desalination off the coast.

Wind mixing occurs during the ice-free season. It occurs most intensely in spring and autumn, when strong winds blow over the sea, and the stratification of waters is not yet very pronounced. At this time, wind mixing extends to horizons of 20-25 m from the surface.

Intense ice formation over most of the sea stimulates enhanced thermohaline winter vertical circulation. At depths of up to 250-300 m, it spreads to the bottom, and below it is prevented by the maximum stability that exists here. In areas with rugged bottom topography, the spread of density mixing into the lower horizons is facilitated by the sliding of water along the slopes.

Ice cover

Severe and long winters with strong northwest winds contribute to the development of large masses of ice in the sea. The ice of the Sea of ​​Okhotsk is an exclusively local formation. Here there are both fixed ice - fast ice, and floating ice, which is the main form of sea ice.

Ice is found in varying amounts in all areas of the sea, but in summer the entire sea is cleared of ice. The exception is the area of ​​the Shantar Islands, where ice can persist in the summer.

Ice formation begins in November in the bays and lips of the northern part of the sea, in the coastal part of the island. Sakhalin and Kamchatka. Then ice appears in the open part of the sea. In January and February, ice covers the entire northern and middle part of the sea.

In normal years, the southern border of the relatively stable ice cover bends to the north and runs from the La Perouse Strait to Cape Lopatka.

The extreme southern part of the sea never freezes. However, thanks to the winds, significant masses of ice are carried into it from the north, often accumulating near the Kuril Islands.

From April to June, destruction and gradual disappearance of the ice cover occurs. On average, sea ice disappears in late May - early June. The northwestern part of the sea, due to currents and the configuration of the shores, is most clogged with ice, which persists until July. Ice cover in the Sea of ​​Okhotsk lasts for 6-7 months. More than 3/4 of the sea surface is covered with floating ice. The compact ice of the northern part of the sea poses serious obstacles to navigation even for icebreakers.

The total duration of the ice period in the northern part of the sea reaches 280 days a year.

The southern coast of Kamchatka and the Kuril Islands belong to areas with little ice cover: here the ice lasts on average no more than three months a year. The thickness of the ice that grows during the winter reaches 0.8-1 m.

Strong storms and tidal currents break up the ice cover in many areas of the sea, forming hummocks and large open waters. In the open part of the sea, continuous, motionless ice is never observed; usually the ice here is drifting, in the form of vast fields with numerous leads.

Some of the ice from the Sea of ​​Okhotsk is carried into the ocean, where it almost immediately collapses and melts. In severe winters, floating ice is pressed against the Kuril Islands by northwestern winds and clogs some straits.

Economic importance

There are about 300 species of fish in the Sea of ​​Okhotsk. Of these, about 40 species are commercial. Basic commercial fish- pollock, herring, cod, navaga, flounder, sea ​​bass, capelin. Salmon catches (chum salmon, pink salmon, sockeye salmon, coho salmon, chinook salmon) are small.

The Sea of ​​Okhotsk, whose resources are great importance for states, it is one of the largest seas belonging to the Pacific Ocean. Located off the coast of Asia. It is separated from the ocean by islands - Hokkaido, the eastern coast of Sakhalin and the chain of Kuril lands.

It is worth noting that this sea is considered the coldest of all those located in the Far East. Even in summer, the temperature above it does not exceed 18 degrees on the southern side, and in the northeast thermometers show 10 degrees - this is the maximum.

Brief description of the Sea of ​​Okhotsk

It is cold and powerful. The Sea of ​​Okhotsk washes the shores of Japan and Russia. In its outline, the reservoir resembles an ordinary trapezoid. The sea stretches from southwest to northeast. The maximum length is 2,463 km and the maximum width is 1,500 km. The coastline is more than 10,000 km long. The depth of the Sea of ​​Okhotsk (an indicator of the maximum depression) is almost 4,000 km. The type of reservoir adjacent to the outskirts of the mainland is mixed.

Volcanic activity extends both to the surface and to the bottom of the sea. When seismic movement or the explosion of an underwater volcano occurs underwater, it can cause huge tsunami waves.

Hydronym

The Sea of ​​Okhotsk, whose resources are used in the economic spheres of two countries (Russia and Japan), received its name from the name of the Okhota River. By official sources previously it was called Lamsky and Kamchatsky. In Japan for a long time The sea was called "Northern". But due to confusion with another body of water of the same name, the hydronym was adapted and now the Sea is called the Sea of ​​Okhotsk.

The importance of the Sea of ​​Okhotsk for Russia

It cannot be overestimated. Since 2014, the Sea of ​​Okhotsk has been classified as inland waters Russian Federation. The state makes full use of its resources. First of all, it is the main supplier of salmon species. These are chum salmon, sockeye salmon, chinook salmon and other representatives of the family. Caviar production is organized here, which is highly valued. It is not for nothing that Russia is considered one of the largest suppliers of this product.

The problems of the Sea of ​​Okhotsk, as well as other bodies of water, have led to a significant decline in populations. It was for this reason that the state had to limit fishing. And this applies not only to the salmon family, but also to other species, such as herring, flounder, and cod.

Industry

Russia has achieved great results in the development of industry on the shores of the Sea of ​​Okhotsk. First of all, these are ship repair enterprises and, of course, fish processing factories. These two areas were modernized in the 90s and are now of great importance for the economic development of the state. Nowadays, many commercial enterprises have appeared here.

Industry is also developing quite well on the island. Sakhalin. Previously, in tsarist times, it was perceived negatively, since it served as a place for exile for people disliked by the rule. Now the picture has changed radically. The industry is thriving, people themselves are eager to come here in order to earn big money.

Kamchatka seafood processing enterprises have entered the world market. Their products are highly appreciated abroad. It meets the standards and is quite popular in many countries.

Thanks to oil and gas fields, Russia is a monopolist in this area. There is not a single state that could supply the same volumes of oil and gas to Europe. That is why a lot of money from the state treasury is invested in these enterprises.

Islands

There are few islands in the Sea of ​​Okhotsk, the largest of which is Sakhalin. Its coastline is heterogeneous: in the northeast there is a lowland, in the southeast it is slightly elevated above sea level, and in the west there is a sandbank.

The Kuril Islands are of particular interest. They are small in size; there are about 30 large ones, but there are also smaller ones. All together they form a seismic belt - the largest on the planet. There are about 100 volcanoes on the Kuril Islands. Moreover, 30 of them are active: they can constantly “disturb” the Sea of ​​Okhotsk.

Resources of the Shantar Islands - fur seals. The largest concentration of this species is observed here. However, recently their production has been regulated in order to avoid complete extermination.

Bays

The shoreline of the reservoir is slightly indented, although it is of great length. There are practically no bays or coves in this area. The Sea of ​​Okhotsk basin is divided into three basins: the Kuril, TINRO and Deryugin depressions.

The largest bays are: Sakhalinsky, Tugursky, Shelikhova, etc. There are also several lips here - sea bays cutting deeply into the land, which form the depression of large rivers. Among them, Penzhinskaya, Gizhiginskaya, Udskaya, and Tauyskaya are distinguished. Thanks to the bays, water exchange in the seas also occurs. And on this moment Scientists call this issue quite problematic.

Straits

They are part of the Okhotsk basin. This is the one important element, which connects the reservoir with and also with the Pacific Ocean. In addition, low and shallow water and Nevelskoy are observed. They do not play a special role, since they are quite small. But the Kruzenshtern and Bussol straits are distinguished by their large area, while their maximum depth reaches 500 meters. In many ways, they regulate the salinity of the Sea of ​​Okhotsk.

Bottom and coastline

The depths of the Sea of ​​Okhotsk are varied. On the side of Sakhalin and the mainland, the bottom is represented by a sandbank - a continuation of the Asian part of the mainland. Its width is approximately 100 km. The rest of the bottom (about 70%) is represented by the continental slope. Near the Kuril Islands, next to the island. Iturup is a diseased cavity. In this place, the depth of the Sea of ​​Okhotsk reaches 2,500 meters. At the bottom of the reservoir, there are two large, elevated sections of relief with rather original names: the hill of the Institute of Oceanology and the USSR Academy of Sciences.

The coastline of the Sea of ​​Okhotsk belongs to different geomorphological forms. Most of them are high and steep slopes. Only the western territory of Kamchatka and the east of the island. Sakhalin have a lowland character. But the northern coast is significantly rugged.

Water exchange

Continental water flow is small. This happens for the reason that all the rivers flowing into the Sea of ​​Okhotsk are not full of water and cannot play a significant role. The most important is r. Amur, it is here that more than half of the total waste flow falls. There are other relatively large rivers. This is Okhota, Uda, Bolshaya, Penzhina.

Hydrological characteristics

The reservoir is complete because the salinity of the Sea of ​​Okhotsk is quite high. It is 32-34 ppm. It decreases closer to the shore, reaching 30 ‰, and in the intermediate layer - 34 ‰.

Most of the territory is covered with floating ice in winter. The lowest water temperature in the cold season ranges from -1 to +2 degrees. In summer depths of the sea warm up to 10-18ºC.

Interesting fact: at a depth of 100 meters there is an intermediate layer of water, the temperature of which does not change throughout the year and is 1.7°C below zero.

Climate Features

The Sea of ​​Okhotsk is located in temperate latitudes. This fact has a great impact on mainland, providing In the cold part of the year, the Aleutian minimum dominates the territory of the reservoir. It greatly influences the northerly winds, which cause storms that continue throughout the winter.

In the warm season, weak south-easterly winds come from the mainland. Thanks to them, the air temperature increases significantly. However, along with them come cyclones, which can subsequently form typhoons. The duration of such a typhoon can be from 5 to 8 days.

Sea of ​​Okhotsk: resources

They will be discussed further. It is known that Natural resources The Sea of ​​Okhotsk is still poorly explored. The sea shelf with its hydrocarbon reserves is of greatest value. Nowadays, 7 are open in Sakhalin, Kamchatka, the Khabarovsk Territory and the Magadan administrative center. The development of these deposits began back in the 70s. However, besides oil, the main wealth of the Sea of ​​Okhotsk is flora and fauna. They are extremely diverse. Therefore, fishing is significantly developed here. The Sea of ​​Okhotsk is home to the most valuable species of salmon fish. Squid are harvested in the depths, and the reservoir ranks first in the world in terms of catching crabs. Recently, mining conditions have become more strict and harsh. And restrictions were introduced on the catch of some fish.

Fur seals, whales, and seals live in the northern waters of the sea. Catching these representatives of the animal world is strictly prohibited. Recently, fishing has been gaining popularity. sea ​​urchins and shellfish. From the plant world they are important different types seaweed. Speaking about the use of the sea, it is worth noting its importance in the transport sector. It is a priority. There are important sea trade routes that connect big cities Korsakov (Sakhalin), Magadan, Okhotsk and others.

Ecological problems

The Sea of ​​Okhotsk, like other waters of the World Ocean, suffers from human activity. Recorded here ecological problems in the form of waste products of oil refining and residual gas compounds. Waste from industrial and household enterprises is also quite problematic.

The coastal zone began to become polluted since the development of the first shelf deposits, but until the end of the 80s it did not occur on such a large scale. Now, anthropogenic human activity has reached a critical point and requires immediate resolution. The greatest concentration of waste and pollution is concentrated off the coast of Sakhalin. This is mainly due to rich oil deposits.

Tidal phenomena in the Kuril ridge area

Tides are the dominant factor determining the dynamics of waters in the straits and largely determine changes in the vertical and horizontal structure of the waters. The tides in the area of ​​the ridge, as in the Sea of ​​Okhotsk, are formed mainly by tidal waves spreading from the Pacific Ocean. The proper tidal movements of the Sea of ​​Okhotsk, caused by the direct influence of tidal forces, are negligible. Tidal waves in the northwestern part of the Pacific Ocean are predominantly progressive in nature and move in a southwestern direction along the Kuril ridge. The speed of movement of tidal waves in the ocean when approaching the Kuril ridge reaches 25-40 knots (12-20 m/s). The amplitude of tidal level fluctuations in the ridge zone does not exceed 1 m, and the speed of tidal currents is about 10-15 cm/s. In the straits, the phase speed of tidal waves decreases, and the amplitude of tidal level fluctuations increases to 1.7-2.5 m. Here, the speeds of tidal currents increase to 5 knots (2.5 m/s) or more. Due to the multiple reflection of tidal waves from the shores of the Sea of ​​Okhotsk, complex forward-standing waves occur in the straits themselves. Tidal currents in the straits have a pronounced reversible character, which is confirmed by measurements of currents at daily stations in the Bussol, Frieza, Catherine and other straits. The horizontal orbits of tidal currents, as a rule, are close in shape to straight lines oriented along the straits.

Wind waves in the Kuril region

IN summer period Both on the Sea of ​​Okhotsk and on the ocean side of the Kuril Islands, large waves (height 5.0 m or more) occur less frequently than in 1% of cases. The frequency of waves with gradations of 3.0–4.5 m is 1-2% on the Sea of ​​Okhotsk side and 3-4% on the ocean side. For a gradation of wave heights of 2.0-2.5 m in the Sea of ​​Okhotsk, the frequency is 28-31%, and from the Pacific Ocean - 32-33%. For weak waves of 1.5 m or less on the Sea of ​​Okhotsk side, the repeatability is 68-70%, and on the ocean side - 63-65%. The prevailing direction of waves in the Kuril part of the Sea of ​​Okhotsk is from the southwest in the south of the region and the central Kuril Islands, to the northwest in the north of the region. On the ocean side of the Kuril Islands, the southwestern direction of waves predominates in the south, and in the north, northwestern and southeastern waves are observed with equal probability.

In autumn, the intensity of cyclones increases sharply, and accordingly they intensify wind speed, which generate larger waves. During this period, along the Sea of ​​Okhotsk coast of the islands, waves with a height of 5.0 m or more account for 6-7% of the total number wave heights, and on the ocean side - 3-4%. The frequency of occurrence of north-west, north-east and south-east directions increases. Dangerous waves are produced by cyclones (typhoons) with a pressure in the center of less than 980 hPa and large gradients of baric pressure - 10-12 hPa at 1° latitude. Typically in September, typhoons enter the southern part of the Sea of ​​Okhotsk, moving along the Kuril ridge

In winter, the intensity of passing cyclones increases. The frequency of waves with a height of 5.0 m or more at this time is 7-8% on the Sea of ​​Okhotsk side, and 5-8% on the ocean side. The prevailing direction of the waves is the north-west and the waves of the neighboring points.

In spring, the intensity of cyclones drops sharply, their depth and range of action decrease significantly. The frequency of large waves throughout the entire water area is 1% or less, and the direction of the waves changes to the southwest and northeast.

Ice conditions

In the Kuril Straits in the autumn-winter period, due to intense tidal mixing and the influx of warmer waters from the Pacific Ocean, the surface water temperature does not reach the negative values ​​necessary for the onset of ice formation. However, constant and strong northerly winds in winter are the main reason for the drift of floating ice in the study area. In severe winters, floating ice extends far beyond its average position and reaches the Kuril Straits. In January, during severe ice-covered years, individual tongues of floating ice emerge from the Sea of ​​Okhotsk into the ocean through the Catherine Strait, spreading 30 to 40 miles into the open part of the ocean. In February, off the Southern Kuril Islands, ice tongues move southwest, along the island of Hokkaido, to Cape Erimo and further south. The width of the ice mass can reach 90 miles. Significant ice masses can be observed along Onekotan Island. The width of the ice strip here can reach 60 miles or more. In March, during extremely difficult years, ice enters the open ocean from the Sea of ​​Okhotsk from a massif in the southwest of the sea through all the straits, starting from Kruzenshtern and further south. Tongues of ice emerging from the straits flow to the southwest, along the Kuril Islands, and then along the island of Hokkaido, to Cape Erimo. The width of the ice mass in various places can reach 90 miles. Off the eastern coast of the Kamchatka Peninsula, the width of the ice massif can reach more than 100 miles, and the massif can extend to Onekotan Island. In April, floating ice can emerge through any strait of the Kuril ridge from the Krusenstern Strait and further south, and the width of the ice tongues does not exceed 30 miles.

The influence of atmospheric circulation on water dynamics

A feature of the atmospheric processes in the Kuril region, as well as the entire Sea of ​​Okhotsk, is the monsoon nature of the atmospheric circulation (Fig. 2.3). This is the predominance of southeast winds during the summer monsoon and the opposite wind directions in the winter. The intensity of monsoon development is determined by the development of large-scale atmospheric processes associated with the state of the main centers of atmospheric action that regulate atmospheric circulation over the seas of the Far Eastern region. A fairly close cause-and-effect relationship has been revealed between the characteristics of atmospheric circulation and the variability of the intensity of development of one or another link in the system of currents in the Kuril Islands region, which, in turn, largely determines the formation of the temperature background of the waters of the region.

CO – “cyclones over the ocean”; OA – “Okhotsk-Aleutian” /

Characteristics of the Soya and Kuril currents in September 1988-1993. (1Св = 10 6 m 3 /s)

The given data on the state of the Kuril currents in September for the period from 1988 to 1993. indicates interannual variability in the characteristics of the system of these currents.

In the spring period of the year, with the predominance of the Okhotsk-Aleutian type of atmospheric circulation, a significant penetration of the Soya Current into the Sea of ​​Okhotsk was noted in the subsequent summer season and, as a result, the formation of an increased temperature background in the water area in the South Kuril region. When the northwestern type of atmospheric circulation predominated in the spring, in the subsequent summer season, on the contrary, there was a slight penetration of the warm Soya Current into the Sea of ​​Okhotsk, a greater development of the Kuril Current and the formation of a lower temperature background in the water area.

Main features of the structure and dynamics of waters in the Kuril region

The structural features of the waters of the Kuril region of the Pacific Ocean are associated with the Kuril Current, which is the western boundary flow in the subpolar circular circulation of the North Pacific Ocean. The current can be traced in the waters of the western modification of the subarctic structure, which has the following characteristics water masses :

1. Surface water mass(0-60 m); in spring°C=2-3°, S‰=33.0‰; in summer°С=8°, S‰=33.0‰.

2. Cold intermediate layer(60-200 m); °С min = 0.3°, S‰ = 33.3‰ with a core at a depth of 75-125 m.

3. Warm midlayer(200-800 m); °С max = 3.5°, S‰ = 34.1‰ with a core at a depth of 300-500 m.

4. Deep(800-3000 m);°С=1.7°, S‰=34.7‰.

5. Pridonnaya(more than 3000 m);°С=1.5°, S‰=34.7‰.

The Pacific waters near the northern straits of the Kuril ridge differ significantly from the waters in the area of ​​the southern straits. The waters of the Kuril Current, formed by the very cold and more desalinated waters of the eastern coast of the Kamchatka Peninsula and Pacific waters, in the zone of the straits of the Kuril ridge mix with the transformed waters of the Sea of ​​Okhotsk. Further, the waters of the Oyashio Current are formed by a mixture of the Sea of ​​Okhotsk waters, transformed in the straits, and the waters of the Kuril Current.

General scheme water circulation The Sea of ​​Okhotsk in general is a large cyclonic circulation, which in the northeastern part of the sea is formed by surface, intermediate and deep Pacific waters entering during water exchange through the northern Kuril Straits. As a result of water exchange through the southern and central Kuril Straits, these waters partially penetrate into the Pacific Ocean and replenish the waters of the Kuril Current. The cyclonic pattern of currents characteristic of the Sea of ​​Okhotsk as a whole, caused by the prevailing cyclonic atmospheric circulation of the atmosphere over the sea, is corrected in the southern part of the sea by the complex bottom topography and local features of the water dynamics of the Kuril Straits zone. In the area of ​​the southern basin there is a stable anticyclonic gyre.

The structure of the waters of the Sea of ​​Okhotsk, defined as the Sea of ​​Okhotsk variety of the subarctic water structure, consists of the following water masses:

1. Surface water mass(0-40 m) with a temperature and salinity of about 2.5° and 32.5 in the spring and, respectively, 10-13° and 32.8 in the summer.

2. Cold intermediate water mass(40-150 m), forming in the Sea of ​​Okhotsk in winter, with core characteristics: °C min = -1.3°, S =32.9 at a depth of 100 m.

Along the Kuril Islands in the Sea of ​​Okhotsk there is a sharp “break” of the core of the cold intermediate layer with a minimum temperature below +1° at a distance of 40-60 miles from the coast of the islands. The “break” of the cold intermediate layer indicates the existence of a pronounced frontal separation of the Sea of ​​Okhotsk intermediate waters proper and transformed waters in the straits during tidal vertical mixing. The frontal section limits the spread of a patch of colder surface water in the water area along the Kuril Islands. That is, the cold intermediate layer in the Sea of ​​Okhotsk is not related to that in the Kuril-Kamchatka Current and is determined by the winter temperature conditions of the area.

3. Transitional water mass(150-600 m), formed as a result of tidal transformation of the upper layer of the Pacific and Sea of ​​Okhotsk waters in the zone of the Kuril Straits (T° = 1.5°, S = 33.7).

4. Deep water mass(600-1300m), manifested in the Sea of ​​Okhotsk in the form of a warm intermediate layer: °C = 2.3°, S = 34.3 at a depth of 750-1000 m.

5. Water mass of the southern basin(more than 1300 m) with characteristics: °C = 1.85, S = 34.7.

In the southern part of the Sea of ​​Okhotsk surface water mass has three modifications. The first modification is low-salt (S<32,5‰), центральная охотоморская формируется преимущественно при таянии льда и располагается до глубины 30 м в период с апреля по октябрь. Вторая - Восточно-Сахалинского течения, наблюдается в слое 0-50 м и характеризуется низкой температурой (<7°) и низкой соленостью (<32,0‰). Третья - теплых и соленых вод течения Соя, являющегося продолжением ветви Цусимского течения, распространяющегося вдоль охотоморского побережья о.Хоккайдо (в слое 0-70 м) от пролива Лаперуза до южных Курильских островов. С марта по май имеет место “предвестник” течения Соя (Т°=4-6°, S‰ =33,8-34,2‰), а с июня по ноябрь - собственно теплое течение Соя с более высокой температурой (до 14-17°) и более высокой соленостью (до 34,5‰).

Straits of the Kuril ridge

The Kuril archipelago, approximately 1,200 km long, has 28 relatively large islands and many small ones. These islands form the Greater Kuril Ridge and the Lesser Kuril Ridge, located along the ocean side of the Greater Kuril Ridge, 60 km southwest of the latter. The total width of the Kuril Straits is about 500 km. Of the total cross-sections of the straits, 43.3% falls on the Bussol Strait (threshold depth 2318 m), 24.4% - on the Kruzenshtern Strait (threshold depth 1920 m), 9.2% - on the Frieza Strait and 8.1% - on the IV Kuril Strait. However, the depth of even the deepest of the Kuril Straits is significantly less than the maximum depth of the areas of the Okhotsk Sea (about 3000 m) and the Pacific Ocean (more than 3000 m) adjacent to the Kuril Islands. Therefore, the Kuril ridge is a natural threshold that fences off the sea depression from the ocean. At the same time, the Kuril Straits are precisely the zone in which water exchange occurs between these basins. This zone has its own characteristics of the hydrological regime, which differ from the regime of the adjacent deep-water areas of the ocean and sea. Features of the orography and topography of the bottom of this zone have a corrective effect on the formation of the water structure and the manifestation of processes such as tides, tidal mixing, currents, etc.

Based on a generalization of long-term observation data, it has been established that in the area of ​​the straits there is a more complex hydrological structure of waters than previously thought. Firstly, the transformation of waters in the straits is not clear. A transformed water structure, which has characteristic features of the Kuril variety of subarctic water structure (characterized by negative anomalies of temperature and positive anomalies of salinity on the surface in the warm half of the year, a thicker cold intermediate layer and smoother extremes of intermediate water masses, including a positive anomaly of minimum temperature), is observed mainly on the shelf of islands, where tidal mixing is more pronounced. In shallow waters, tidal transformation leads to the formation of a vertically homogeneous water structure. In the deep-water areas of the straits, well-stratified waters are observed. Secondly, the difficulty lies in the fact that the zone of the Kuril Straits is characterized by the presence of multi-scale inhomogeneities that are formed during vortex formation and frontogenesis during the contact of jets of the Kuril currents, which occurs against the background of tidal mixing. At the same time, in the structure of thermohaline fields there is a change in the position of the boundaries and extrema of the intermediate layers. In areas of vortices, as well as in areas of current cores that carry and retain their characteristics, localization of homogeneous nuclei of the minimum temperature of the cold intermediate layer is observed. Third, the structure of waters in the strait zones is adjusted by the variability of water exchange in the straits. In each of the main Kuril Straits in different years, depending on the development of one or another link in the current system of the area, either the predominant flow of the Sea of ​​Okhotsk waters, or the predominant supply of Pacific waters, or two-way water circulation is possible.

IV Kuril Strait

IV Kuril Strait is one of the main northern straits of the Kuril island chain. The cross-section of the strait is 17.38 km 2, which is 8.1% of the total cross-sectional area of ​​all the Kuril Straits, its depth is about 600 m. The topographical feature of the strait is its openness towards the Sea of ​​Okhotsk and the presence of a threshold about 400 m deep on the side Pacific Ocean.

Thermohaline structure of the waters of the IV Kuril Strait

Due to the complex bottom topography in the strait, the amount of water masses varies. In shallow waters, vertical mixing leads to homogenization of waters. In these cases, only surface water mass occurs. For the main part of the strait, where the depth is 500-600 m, two water masses are observed - surface and cold intermediate. At deeper stations on the Sea of ​​Okhotsk side, a warmer bottom water mass is also observed. At some stations of the strait a second minimum temperature is observed. Since there is a threshold with a depth of about 400 m in the strait from the Pacific Ocean, water exchange between the Pacific Ocean and the Sea of ​​​​Okhotsk practically occurs to the depth of the threshold. That is, the Pacific and Sea of ​​Okhotsk water masses, located at great depths, do not have contact in the strait zone.

Krusenstern Strait

The Krusenstern Strait is one of the largest and deepest straits of the Kuril island chain. The cross-sectional area of ​​the strait is 40.84 km 2 . The threshold of the strait, with depths of 200-400 m, is located on its ocean side. There is a trench in the strait with depths from 1200 m to 1990 m, through which deep water can be exchanged between the Pacific Ocean and the Sea of ​​Okhotsk. North-eastern part The strait occupies shallow water with depths of less than 200 m. Unlike other straits of the Kuril ridge, the system of islands and straits (Nadezhda and Golovnin straits), which are essentially part of the Krusenstern Strait, is formed by a group of small islands and rocks, bounded from the south by the island of Simushir and from the north the island of Shiashkotan.

Thermohaline structure of the waters of the Krusenstern Strait

Sea of ​​Okhotsk (from the name of the river Okhota)

Lama Sea (from Evenki lama - sea), Kamchatka Sea, a semi-enclosed sea in the northwestern part of the Pacific Ocean, limited by the eastern coast of the continent of Asia from Cape Lazarev to the mouth of the Penzhina River, the Kamchatka Peninsula, the Kuril Islands, Hokkaido and Sakhalin. It washes the coasts of the USSR and Japan (Hokkaido Island). It is connected to the Pacific Ocean through the Kuril Straits, with Sea of ​​Japan- through the Nevelskoy and La Perouse straits. Length from north to south 2445 km, maximum width 1407 km. Area 1583 thousand. km 2, average water volume 1365 thousand. km 3, average depth 177 m, largest - 3372 m(Kuril Basin).

The coastline is slightly indented, its length is 10460 km. The largest bays are: Shelikhova (with Gizhiginskaya and Penzhinskaya bays), Sakhalinsky, Udskaya bay, Tauyskaya bay, Academy, etc. On the southeastern coast of the island. Sakhalin - Aniva and Terpeniya bays. Most of the northern, northwestern and northeastern coasts are elevated and rocky. In the mouth areas of large rivers, as well as in western Kamchatka, in the northern part of Sakhalin and Hokkaido, the banks are predominantly low-lying. Almost all the islands: Shantarskie, Zavyalova, Spafareva, Yamskie and others are located off the coast, and only the Iona islands are in the open sea. Large rivers flow into the Omsk: Amur, Uda, Okhota, Gizhiga, and Penzhina.

Relief and geology of the bottom. O. m. is located in the zone of transition of the continent to the ocean floor. The sea basin is divided into two parts: northern and southern. The first is immersed (up to 1000 m) continental shelf; within its boundaries there are: the hills of the USSR Academy of Sciences and the Institute of Oceanology, occupying the central part of the sea, the Deryugin depression (near Sakhalin) and Tinro (near Kamchatka). The southern part of the Ocean Ocean is occupied by the deep-sea Kuril Basin, which is separated from the ocean by the Kuril island ridge. Coastal sediments are terrigenous, coarse-grained, in the central part of the sea - diatomaceous silts. The earth's crust under the ocean is represented by continental and subcontinental types in the northern part and suboceanic type in the southern part. The formation of the Omsk basin in the northern part occurred in Anthropogenic times, as a result of the subsidence of large blocks of continental crust. The deep-sea Kuril Basin is much more ancient; it was formed either as a result of the subsidence of a continental block, or as a result of the separation of part of the ocean floor.

Climate. O. M. lies in the monsoon climate zone of temperate latitudes. For most of the year, cold, dry winds blow from the mainland, cooling the northern half of the sea. From October to April, negative air temperatures and stable ice cover are observed here. On the north-east average monthly air temperatures in January - February from - 14 to - 20 ° C, in the north and west from - 20 to - 24 ° C, in the southern and eastern parts of the sea from - 5 to - 7 ° C; average monthly temperatures in July and August, respectively, are 10-12° C, 11-14° C, 11-18° C. Annual precipitation is from 300-500 mm in the north up to 600-800 mm in the west, in the southern and southeastern parts of the sea - over 1000 mm. In the northern half of the sea, cloudiness is less than in the southern half, increasing from west to east.

In the water balance of the ocean, surface runoff, precipitation, and evaporation play an insignificant role; its main part is formed by the inflow and outflow of Pacific water and the influx of water from the Sea of ​​Japan through the La Perouse Strait. Pacific deep water enters through the straits of the Kuril Islands below 1000-1300 m. Its temperature (about 1.8-2.3 ° C) and salinity (about 34.4-34.7 ‰) change little throughout the year. Surface water of Okhotsk occupies a layer with a depth of up to 300-500 m and with the exception of the coastal zone, it is observed throughout the entire sea. Its temperature in winter is from - 1.8 to 2 ° C, in summer from - 1.5 to 15 ° C, salinity is from 32.8 to 33.8 ‰. As a result of winter convection, an intermediate layer of water with a thickness of 150-900 is formed between the lower boundary of surface water and the upper boundary of deep Pacific water. m with temperatures throughout the year from - 1.7 to 2.2 ° C and salinity from 33.2 to 34.5 ‰. In the Omsk region there is a pronounced, although with numerous local deviations, cyclonic system of currents with small (up to 2-10 cm/sec) speeds away from the coast. In narrow places and straits strong tidal currents (up to 3.5 m/sec in the Kuril Straits and in the area of ​​the Shantar Islands). In the ocean, tides of mixed type, predominantly irregular diurnal, predominate. Maximum tide (12.9 m) is observed in Penzhinskaya Bay, minimal (0.8 m) - near the southeastern part of Sakhalin. In November, the northern part of the sea is covered with ice, while the middle and southern parts, exposed to incoming cyclones and occasionally typhoons, become the site of severe storms that often do not subside from 7 to 10 days. Water transparency Om. far from the shores is 10-17 m, near the coast it decreases to 6-8 m and less. O. m. is characterized by the phenomenon of glow of water and ice.

Vegetation and fauna. Based on the species composition of organisms living in the Arctic Ocean, it has an arctic character. Species of the temperate (boreal) zone, due to the thermal effects of oceanic waters, are inhabited mainly by the southern and southeastern parts of the sea. The phytoplankton of the sea is dominated by diatoms, while the zooplankton is dominated by copepods and jellyfish, larvae of mollusks and worms. In the littoral zone (See Littoral) there are numerous settlements of mussels, littorinae and other mollusks, barnacles, sea urchins, and many crustaceans of amphinodes and crabs. At great depths of the ocean, a rich fauna of invertebrates (glass sponges, sea cucumbers, deep-sea eight-rayed corals, decapod crustaceans) and fish has been discovered. The richest and most widespread group of plant organisms in the littoral zone are brown algae. Red algae are also widespread in the Omsk region, and green algae are widespread in the northwestern part. Of the fish, the most valuable are salmon: chum salmon, pink salmon, coho salmon, chinook salmon, and sockeye salmon. Commercial concentrations of herring, pollock, flounder, cod, navaga, capelin, and smelt are known. Mammals live here - whales, seals, sea lions, fur seals. Kamchatka crabs, blue crabs, or flat-footed crabs (the O. m. ranks first in the world in terms of commercial crab reserves) and salmon fish are of great economic importance.

Important sea routes linking Vladivostok with northern regions Far East And Kuril Islands. Large ports on the coast of the mainland are Magadan (in Nagaev Bay), Okhotsk, on the island of Sakhalin - Korsakov, on the Kuril Islands - Severo-Kurilsk.

O. m. was opened in the 2nd quarter of the 17th century. Russian explorers I. Yu. Moskvitin and V. D. Poyarkov. In 1733, the work of the Second Kamchatka Expedition began, whose participants photographed almost all the shores of the Sea. In 1805, I. F. Kruzenshtern carried out an inventory of the eastern coast of Sakhalin Island. During 1849-55, G. I. Nevelskoy undertook a survey of the southwestern shores of the O. m. and the mouth of the river. The Amur proved that there is a strait between Sakhalin and the mainland. The first complete summary of sea hydrology was given by S. O. Makarov (1894). From works of the early 20th century. for knowledge of the fauna of O. m. large value have studies by V.K. Brazhnikov (1899-1902) and N.K. Soldatov (1907-13). From foreign expeditions of the late 19th - early 20th centuries. It should be noted the American expeditions of Ringald, Rogers and the US Fisheries Commission on the ship "Albatross", the Japanese expedition of 1915-1917 under the leadership of H. Marukawa. After October revolution 1917 complex research papers under the leadership of K. M. Deryugin a and P. Yu. Shmidt a. In 1932, a complex expedition of the State Hydrological Institute and the Pacific Institute of Fisheries worked in Omsk on the ship Gagara. After this expedition, systematic research in the ocean was carried out for a number of years by the Pacific Research Institute of Fisheries and Oceanography. Since 1947, oceanic oceans began to be studied by the Institute of Oceanology of the USSR Academy of Sciences on the ship “Vityaz” (1949–54), by ships of the State Oceanographic Institute, the Vladivostok Hydrometeorological Administration, and other institutions.

Lit.: Makarov S. O., “Vityaz” and the Pacific Ocean, vol. 1-2, St. Petersburg, 1894; Leonov A.K., Regional oceanography, part 1, Leningrad, 1960.

T. I. Supranovich, V. F. Kanaev.

Sea of ​​Okhotsk.

Great Soviet Encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .

See what the “Sea of ​​Okhotsk” is in other dictionaries:

Sea of ​​Okhotsk ... Wikipedia

Pacific Ocean, near the east. coast of the Asian part of Russia. The name appeared in the middle of the 18th century. Given after the Okhotsk fort (modern Okhotsk), which was named after the Okhota River (distorted Evensk okat river). In the XVII-XVIII centuries. also called Tunguska... ... Geographical encyclopedia

SEA OF OKHOTSK, a semi-enclosed sea of ​​the Pacific Ocean, off the coast of Asia. Separated from the ocean by the Kamchatka Peninsula, the ridge of the Kuril Islands and the island. Hokkaido. The Nevelsk, Tatar and La Perouse straits communicate with the Sea of ​​Japan, the Kuril Strait with the Pacific... ... Russian history

Sea of ​​Okhotsk- (Tunguzskoye or Lamutskoye), borders the shores of Sakhalin, Primorsky region. and Kamchatka and the Kurilsk chain. oh wow; Tatarsky and Laperuzov. It connects with Japan through straits. sea, and nearby straits between Kurilsk. about you and Tikh. ok m. V… … Military encyclopedia

Semi-enclosed sea of ​​the Pacific Ocean, off the coast of Asia. Separated from the ocean by the Kamchatka Peninsula, the ridge of the Kuril Islands and the island. Hokkaido. Prol. Nevelskoy, Tatarskiy and La Perouse are connected to the Japanese metro station and the Kuril Strait. with Quiet approx. 1603 thousand km².… … Big encyclopedic Dictionary

The semi-enclosed sea of ​​the Pacific Ocean, off the coast of Asia. Separated from the ocean by the Kamchatka Peninsula, the Kuril Islands and the island. Hokkaido. The Nevelsk, Tatar and La Perouse straits communicate with the Sea of ​​Japan, the Kuril Straits with the Pacific Ocean... encyclopedic Dictionary

Sea of ​​Okhotsk- Coast of the Sea of ​​Okhotsk. SEA OF OKHOTSK, Pacific Ocean, off the coast of Eurasia. Separated from the ocean by the Kamchatka Peninsula, the Kuril Islands, and the island of Hokkaido. Area 1603 thousand km 2. Depth up to 3521 m. Shantar Islands. Large bays of Shelikhov... Illustrated Encyclopedic Dictionary

A vast basin located in NE Asia, belonging to the Pacific Ocean. It is located between parallels 44° and 62° 16 s. w. and meridians 135° 15th and 163° 15th century. d. The sea is most extended along the meridian; so from Penzhinskaya Bay to the south. borders... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Ephron

SEA OF OKHOTSK- a marginal sea of ​​the Pacific Ocean, separated from it by the Kamchatka Peninsula, the chain of the Kuril Islands and the Hokkaido Island. It is connected to the Japanese Cape by narrow and shallow straits. Nevelskoy and La Perouse, with the Quiet approx. prol. Kuril ridge. Avg. depth 821 m, max... Marine encyclopedic reference book

Between the waters of the Japanese and Bering Seas is the Sea of ​​Okhotsk.

This body of water borders the territory of Japan and the Russian Federation and acts as the most important port point on the map of our country.

Previously, among the names of the sea were Lamskoye, Kamchatka, and among the Japanese - Hokkai, i.e. Northern.

Shores of the Sea of ​​Okhotsk

This body of water is considered to be one of the largest and deepest in Russia, as well as the coolest Far Eastern sea. The water area is 1603 km 2, and the depth is over 800 m on average. The maximum depth is almost 4 thousand meters. The coastal boundary of the reservoir is quite flat, with several bays running along it. However, in the northern part of the waters there are many rocks and sharp drop-offs. For the territory of this sea, storm warnings are completely normal.

The sea is separated from the Pacific Ocean by the Kuril Islands. We are talking about 3 dozen small areas of land that are located in a seismic zone due to the abundance of volcanoes. Also, the waters of the Pacific Ocean and the Sea of ​​​​Okhotsk are separated by Kamchatka and the island of Hokkaido. And the largest island in this area is Sakhalin. Some straits of the reservoir act as a conditional border with the Sea of ​​Japan. Among the largest rivers flowing into the sea, it is worth noting the Amur, Bolshaya, Penzhina, and Okhota.

Cities on the Sea of ​​Okhotsk

The main ports and cities of the Okhotsk water area include:

• Ayan, Okhotsk and Magadan on the mainland;
• Korsakov on Sakhalin Island;
• Severo-Kurilsk on the Kuril Islands.

Fisheries of the Sea of ​​Okhotsk

(Private fishing: fishing on the shores of the Sea of ​​Okhotsk, which is only permitted during the open fishing season, but certain species, such as crab, require a permit, otherwise it may be considered poaching)

Natural resources of this north sea very diverse. Fishing, salmon caviar production and seafood production are actively developing on the territory of the reservoir. Famous inhabitants of these regions are pink salmon, sockeye salmon, cod, chum salmon, coho salmon, flounder, Chinook salmon, herring, crabs and squid, pollock, and navaga. In addition, there is limited hunting of fur seals on the Shantar Islands. Nowadays, fishing for shellfish, sea urchins and kelp is also popular.

(Fishing boat in the Sea of ​​Okhotsk)

Industry in the Sea of ​​Okhotsk began to develop in the 90s. First of all, we are talking about ship repair factories and fish processing enterprises on Sakhalin. Hydrocarbon raw materials are also being developed in the Sakhalin region. Currently, 7 points with oil deposits have been discovered in the sea area, which began to be developed back in the 70s. last century.