Sea of Japan, features of tourism. Currents in the Sea of Japan The Sea of Japan is warm

The Sea of Japan is a marginal sea of the Pacific Ocean and is limited by the coasts of Japan, Russia and Korea. The Sea of Japan communicates through the Korea Strait in the south with the East China and Yellow Seas, through the Tsugaru (Sangara) Strait in the East with Pacific Ocean and through the La Perouse and Tatar Straits in the north with the Sea of Okhotsk. The area of the Sea of Japan is 980,000 km2, the average depth is 1361 m. The northern border of the Sea of Japan runs along 51 ° 45 "N latitude (from Cape Tyk on Sakhalin to Cape Yuzhny on the mainland). The southern border runs from the island of Kyushu to the Goto Islands and from there to Korea [Cape Kolcholkap (Izgunov)]

The Sea of Japan has an almost elliptical shape with the major axis in the direction from southwest to northeast. Along the coast there are a number of islands or island groups - these are the islands of Iki and Tsushima in the middle part of the Korean Strait. (between Korea and Kyushu Island), Ulleungdo and Takashima east coast Korea, Oki and Sado off the west coast of Honshu Island (Hondo) and Tobi Island off the northwestern coast of Honshu (Hondo).

Bottom relief

The straits connecting the Sea of Japan with the marginal seas of the Pacific Ocean are characterized by shallow depths; only the Korea Strait has depths of more than 100 m. Bathymetrically, the Sea of Japan can be divided by 40° N. w. into two parts: northern and southern.

The northern part has a relatively flat bottom topography and is characterized by an overall smooth slope. Maximum depth(4224 m) is observed in the area of 43°00"N, 137°39"E. d.
The bottom topography of the southern part of the Sea of Japan is quite complex. In addition to the shallow waters around the islands of Iki, Tsushima, Oki, Takashima and Ulleungdo, there are two large isolated
jars separated by deep grooves. This is the Yamato Bank, opened in 1924, in the area of 39°N, 135°E. etc., and the Shunpu Bank (also called the Northern Yamato Bank), opened in 1930 and located approximately 40° N. latitude, 134° east. d. The smallest depths of the first and second banks are 285 and 435 m, respectively. A depression with a depth of more than 3000 m was discovered between the Yamato Bank and the island of Honshu.

Hydrological regime

Water masses, temperature and salinity. The Sea of Japan can be divided into two sectors: warm (from Japan) and cold (from Korea and Russia (Primorsky Territory). The boundary between the sectors is the polar front, running approximately along the parallel of 38-40 ° N, i.e. almost along the same latitudes along which the polar front passes in the Pacific Ocean east of Japan.

Water masses

The Sea of Japan can be divided into surface, intermediate and deep. The surface water mass occupies a layer up to approximately 25 m and in summer is separated from the underlying waters by a clearly defined thermocline layer. The surface water mass in the warm sector of the Sea of Japan is formed by the mixing of surface waters of high temperature and low salinity coming from the East China Sea and the coastal waters of the Japan Islands region, in the cold sector - by the mixing of waters formed when ice melts from early summer to autumn , and the waters of Siberian rivers.

The surface water mass exhibits the largest fluctuations in temperature and salinity depending on the season and region. Thus, in the Korea Strait, the salinity of surface waters in April and May exceeds 35.0 ppm. which is higher than the salinity in the deeper layers, but in August and September the salinity of surface waters drops to 32.5 ppm. At the same time, in the area of the island of Hokkaido, salinity varies only from 33.7 to 34.1 ppm. In summer surface water temperature 25°C, but in winter it varies from 15°C in the Korea Strait to 5°C near the island. Hokkaido. IN coastal areas in Korea and Primorye, changes in salinity are small (33.7-34 ppm). The intermediate water mass, which lies below the surface water in the warm sector of the Sea of Japan, has high temperature and salinity. It is formed in the intermediate layers of Kuroshio west of Kyushu Island and enters the Sea of Japan from there during the period of early winter to early summer.

However, based on the distribution of dissolved oxygen, intermediate water can also be observed in the cold sector. In the warm sector, the core of the intermediate water mass is located approximately in the 50 m layer; salinity is about 34.5 ppm. The intermediate water mass is characterized by a rather strong decrease in vertical temperature - from 17 ° C at a depth of 25 m to 2 ° C at a depth of 200 m. The thickness of the layer of intermediate water decreases from the warm to the cold sector; in this case, the vertical temperature gradient for the latter becomes much more pronounced. The salinity of intermediate waters is 34.5–34.8 ppm. in the warm sector and about 34.1 industrial. in the cold. The highest salinity values are observed here at all depths - from the surface to the bottom.

The deep water mass, usually called the water of the Sea of Japan itself, has extremely uniform temperature (about 0-0.5 ° C) and salinity (34.0-34.1 ppm). More detailed studies by K. Nishida, however, showed that the temperature of deep waters below 1500 m increases slightly due to adiabatic heating. At the same horizon, a decrease in oxygen content to a minimum is observed, and therefore it is more logical to consider waters above 1500 m as deep, and below 1500 m as bottom. Compared to the waters of other seas, the oxygen content in the Sea of Japan at the same depths is exceptionally high (5.8-6.0 cm3/l), which indicates the active renewal of water in the deep layers of the Sea of Japan. The deep waters of the Sea of Japan are formed mainly in February and March as a result of the subsidence of surface waters in the northern part of the Sea of Japan due to horizontal diffusion, cooling in winter and subsequent convection, after which their salinity increases to approximately 34.0 ppm.

Sometimes surface waters of low salinity of the cold sector (1-4° C, 33.9 prom.) wedge into the polar front and deepen into south direction, going under the intermediate waters of the warm sector. This phenomenon is similar to the penetration of subarctic intermediate water below the warm Kuroshio layer in the Pacific Ocean in the area north of Japan.

In spring and summer, the salinity of warm waters from the East China Sea and cold waters east of Korea decreases due to precipitation and melting ice. These less saline waters mix with surrounding waters and the overall salinity of the surface waters of the Sea of Japan decreases. Additionally, these surface waters gradually warm up during the warmer months. As a result, the density of surface waters decreases, which leads to the formation of a clearly defined upper thermocline layer that separates the surface waters from the underlying intermediate waters. The upper thermocline layer is located in summer season at a depth of 25 m. In autumn, heat is transferred from the sea surface to the atmosphere. Due to mixing with underlying water masses, the temperature of surface waters decreases and their salinity increases. The resulting intense convection leads to a deepening of the upper thermocline layer to 25–50 m in September and 50–100 m in November. In autumn, intermediate waters of the warm sector are characterized by a decrease in salinity due to the influx of waters of the Tsushima Current with lower salinity. At the same time, convection in the surface water layer intensifies during this period. As a result, the thickness of the intermediate water layer decreases. In November, the upper thermocline layer disappears completely due to the mixing of overlying and underlying waters. Therefore, in autumn and spring there is only an upper homogeneous layer of water and an underlying cold layer, separated by a layer of lower thermocline. The latter for most of the warm sector is located at a depth of 200-250, but to the north it rises and off the coast of the island of Hokkaido is located at a depth of about 100 m. In the warm sector of the surface layer, temperatures reach a maximum in mid-August, although in the northern part of the Sea of Japan they spread to the depths. The minimum temperature is observed in February–March. On the other hand, the maximum surface layer temperature off the Korean coast is observed in August. However, due to the strong development of the upper thermocline layer, only a very thin surface layer is heated. Thus, temperature changes in the 50-100 m layer are almost entirely due to advection. Due to the low temperatures characteristic of most of the Sea of Japan for quite great depths, the waters of the Tsushima Current are greatly cooled as they move north.

The waters of the Sea of Japan are characterized by exceptionally high levels of dissolved oxygen, partly due to the abundance of phytoplankton. The oxygen content at almost all horizons here is about 6 cm3/l or more. Particularly high oxygen content is observed in surface and intermediate waters, with a maximum value at the horizon of 200 m (8 cm3/l). These values are much higher than at the same and lower horizons in the Pacific Ocean and the Sea of Okhotsk (1-2 cm3/l).

Surface and intermediate waters are most saturated with oxygen. The percentage of saturation in the warm sector is 100% or slightly lower, and the waters near Primorsky Krai and Korea are oversaturated with oxygen due to low temperatures. north coast In Korea it is 110% and even higher. In deep waters there is a very high oxygen content right down to the bottom.

Color and transparency

The color of the water of the Sea of Japan (according to the color scale) in the warm sector is bluer than in the cold sector, corresponding to the region of 36-38° N. latitude, 133-136° east. etc. index III and even II. In the cold sector this is mainly the color of indices IV-VI, and in the Vladivostok region it is above III. In the northern part of the Sea of Japan, the sea water has a greenish color. Transparency (by the white disk) in the Tsushima Current region is more than 25 m. In the cold sector it sometimes drops to 10 m.

Currents of the Sea of Japan

The main current of the Sea of Japan is the Tsushima Current, which originates in the East China Sea. It is strengthened mainly by the branch of the Kuroshio Current, going to the SOUTHWEST of the island. Kyushu, as well as partially by coastal runoff from China. The Tsushima Current contains surface and intermediate water masses. The current enters the Sea of Japan through the Korea Strait and is directed along the north west bank Japan. There, a branch of the warm current, called the East Korean Current, separates from it, which goes in the north, to the coast of Korea, to the Korean Gulf and Ulleungdo Island, then turns to the SE and connects with the main flow.

The Tsushima Current, about 200 km wide, washes the shores of Japan and goes further to the NE at a speed of 0.5 to 1.0 knots. Then it divides into two branches - the warm Sangar Current and the warm La Perouse Current, which respectively exit into the Pacific Ocean through the Tsugaru (Sangarsky) Strait and into the Sea of Okhotsk through the La Perouse Strait. Both of these currents, after passing through the straits, turn east and go, respectively, close to eastern shore the island of Honshu and the northern coast of Hokkaido.

There are three cold currents in the Sea of Japan: the Liman current, moving at low speed to the southwest in the area north of the Primorsky Territory, the North Korean current, going south in the Vladivostok area to eastern Korea, and the Primorsky current, or the cold current in the middle part of the Sea of Japan, which originates in the area Tatar Strait and goes to the central part of the Sea of Japan, mainly to the entrance to the Tsugaru (Sangara) Strait. These cold currents form a counterclockwise circulation and, in the cold sector of the Sea of Japan, contain clearly defined layers of surface and intermediate water masses. There is a clear boundary of the “polar” front between the warm and cold currents.

Because the Tsushima Current contains surface and intermediate water masses that are about 200 m thick and is separated from the underlying deep water, the thickness of this current is basically of the same order.

The current speed is almost constant to a depth of 25 m, and then decreases with depth to 1/6 of the surface value at a depth of 75 m. The flow rate of the Tsushima Current is less than 1/20 of the flow rate of the Kuroshio Current.

The speed of cold currents is about 0.3 knots for the Liman Current and less than 0.3 knots for the Primorsky Current. The cold North Korean Current, which is the strongest, has a speed of 0.5 knots. The width of this current is 100 km, thickness - 50 m. Basically, cold currents in the Sea of Japan are much weaker than warm ones. The average speed of the Tsushima Current passing through the Korean Strait is lower in winter, and increases to 1.5 knots in summer (in August). For the Tsushima Current, interannual changes are also observed, with a clear period of 7 years being distinguished. The flow of water into the Sea of Japan mainly occurs through the Korea Strait, since the inflow through the Tartary Strait is very insignificant. The flow of water from the Sea of Japan occurs through the Tsugaru (Sangara) and La Perouse Straits.

Tides and tidal currents

Tides are low for the Sea of Japan. While off the coast of the Pacific Ocean the tide is 1-2 m, in the Sea of Japan it reaches only 0.2 m. Slightly higher values are observed off the coast of the Primorsky Territory - up to 0.4-0.5 m. In the Korean and Tatar Territories In the straits, the tide increases, reaching more than 2 m in some places.

Tidal waves propagate at right angles to these cotidal lines. West of Sakhalin and in the area of the Korean Strait. two points of amphidromy are observed. A similar cotidal map can be constructed for the lunisolar diurnal tide. In this case, the amphidromy point is located in the Korea Strait Since total area Since the cross-section of the La Perouse and Tsugaru straits is only 1/8 of the cross-sectional area of the Korea Strait, and the cross-section of the Tartary Strait is generally insignificant, the tidal wave comes here from the East China Sea mainly through the Eastern Passage (Tsushima Strait). The magnitude of forced fluctuations in the mass of water in the entire Sea of Japan is practically negligible. The resulting component of tidal currents and the eastward Tsushima Current sometimes reaches 2.8 knots. In the Tsugaru (Soigarsky) Strait, a tidal current of the diurnal type predominates, but the magnitude of the semidiurnal tide is greater here.

There is a clear diurnal inequality in tidal currents. The tidal current in the La Perouse Strait is less pronounced due to the difference in levels between the Sea of Okhotsk and the Sea of Japan. There is also a diurnal inequality here. In the La Perouse Strait, the current is directed mainly to the east; its speed sometimes exceeds 3.5 knots.

Ice Conditions

Freezing of the Sea of Japan begins in mid-November in the area of the Tatar Strait and in early December in the upper reaches of Peter the Great Bay. In mid-December, areas near the northern part of Primorsky Krai and Peter the Great Bay freeze. In mid-December, ice appears in the coastal areas of Primorsky Krai. In January, the area of ice cover increases further from the coast to the side open sea. With the formation of ice, navigation in these areas naturally becomes difficult or stops. The freezing of the northern part of the Sea of Japan is somewhat delayed: it begins in early to mid-February.

Ice melting begins in areas furthest from the coast. In the second half of March, the Sea of Japan, with the exception of areas close to the coast, is already free of ice. In the northern part of the Sea of Japan, ice off the coast usually melts in mid-April, at which time navigation in Vladivostok resumes. The last ice in the Tartary Strait is observed in early to mid-May. The period of ice cover along the coast of the Primorsky Territory is 120 days, and near the De-Kastri harbor in the Strait of Tartary - 201 days. There is not much ice observed along the northern coast of the DPRK. On the western coast of Sakhalin, only the city of Kholmsk is free of ice, since a branch of the Tsushima Current enters this area. The remaining areas of this coast freeze for almost 3 months, during which navigation stops.

Geology

The continental slopes of the Sea of Japan basin are characterized by many submarine canyons. On the mainland side, these canyons stretch to depths of more than 2000 m, and on the side of the Japanese Islands only to 800 m. The mainland shoals of the Sea of Japan are poorly developed, the edge runs at a depth of 140 m on the mainland side and at a depth of more than 200 m. Yamato Bank and other banks The Sea of Japan is composed of bedrock consisting of Precambrian granites and other Paleozoic rocks and overlying Neogene igneous and sedimentary rocks. According to paleogeographic studies, South part The modern Sea of Japan was probably dry land in the Paleozoic and Mesozoic and during most of the Paleogene. It follows from this that the Sea of Japan was formed during the Neogene and early Quaternary periods. The absence of a granite layer in the earth's crust of the northern part of the Sea of Japan indicates the transformation of the granite layer into a basaltic layer due to basification, accompanied by subsidence earth's crust. The presence of “new” oceanic crust here can be explained by the stretching of continents accompanying the general expansion of the Earth (Egayed’s theory).

Thus, we can conclude that the northern part of the Sea of Japan was once dry land. The current presence of such a large amount of continental material on the bottom of the Sea of Japan at depths of more than 3000 m should indicate that the land subsided to a depth of 2000-3000 m in the Pleistocene.

The Sea of Japan currently has a connection with the Pacific Ocean and the surrounding marginal seas through the Korean, Tsugaru (Saigarsky), La Perouse and Tatar straits. However, the formation of these four straits occurred during very recent geological periods. The oldest strait is the Tsugaru (Sangara) Strait; it already existed during the Wisconsinian glaciation, although it may have been filled with ice several times after that and used in the migration of land animals. The Korea Strait was also dry land at the end of the Tertiary period, and was used by southern elephants to migrate to Japanese islands This strait opened only at the beginning of the Wisconsin glaciation. The La Perouse Strait is the youngest. Fossilized remains of mammoths found on the island of Hokkaido indicate the existence of an isthmus. land on the site of this strait until the end of the Wisconsin glaciation

The Sea of Japan is considered one of the largest and deepest seas in the world. It is a marginal sea of the Pacific Ocean.

Origin

The first information about this sea was received from Chinese sources in the 2nd century BC. Historically, it is believed that this reservoir was formed as a result of the melting of a glacier and rising water levels in the world's oceans.

Historical events

In the 14th-16th centuries, pirates seized power at sea. All maritime trade was under their control. From 1603 to 1867, the Sea of Japan was one of the busiest transport links and the main route of entry for the Dutch and Korean embassies.

Sea of Japan on the map photo

The Sea of Japan witnessed Russo-Japanese War(1901-1902). Today, the Sea of Japan is an important domestic and international transport artery.

Characteristic

Main characteristics of the Sea of Japan:

Area 1,062,000 square km
Average sea depth: 1536 m.
Greatest depth: 3742 m.
Salinity: 34-35 ‰.
Length: from north to south 2,255 km, from west to east about 1,070 km.
In winter, part of the Sea of Japan freezes - the Russian coastal side, but the ice can break up periodically;
Average annual temperature: in the north 0-12C, in the south 17-26C.

shore of the Sea of Japan photo

Currents

The main current of the Sea of Japan is the Tsushima, whose width is approximately 200 km. This current contains surface and intermediate water masses. In addition, the following cold currents are observed in the Sea of Japan:

Limanskoye, moving at low speed to the southwest;
North Korean, going south;
Coastal, or cold current, going to the central part.

Japanese Sea. Primorsky Krai photo

These cold currents form a counterclockwise circulation. The warm Kuroshio Current prevails in the southern part of the sea.

What rivers flow into

Few rivers flow into the Sea of Japan, most of them are mountainous. Let us note the largest of them:

Partisan;
Tumnin;
Samarga;
Rudnaya.

Where does the Sea of Japan flow into?

Sea waters enter through the straits:

through the Nevelsky Strait to the Sea of Okhotsk;
through the Sangar Strait to the Pacific Ocean;
through the Korea Strait into the East China Sea.

Japanese Sea. storm photo

Climate

The climate of the sea is monsoon, temperate. The western and northern parts of the sea are much colder than the southern and eastern. The temperature difference reaches +27 C. Hurricanes and typhoons often pass over the sea surface.

Despite the fact that the sea is separated from the ocean by the Japanese islands and Sakhalin, storms and hurricanes often rage in the northern part of the sea, especially in autumn. Such exposure can last up to three days, and the waves reach 12 meters in height. The Siberian anticyclone brings such weather. For this reason, the Sea of Japan is not very calm for shipping.

Japanese Sea. port of Vladivostok photo

In November, the northern part of the sea is covered with ice, and in March-April the ice breaks up. In summer the weather is cloudy and weak monsoon winds from the southeast prevail.

Relief

The bottom topography of the Sea of Japan is divided into:

the northern part (a wide trench that narrows and rises to the north);
the central part (a deep closed basin, elongated in a northeast direction);
the southern part (the terrain is complex, alternating shallow water with troughs).

The shores of this sea are mostly mountainous. Low-lying coastlines are extremely rare. Coastline quite flat on Sakhalin. The shores of Primorye are more rugged.

underwater world of the Sea of Japan photo

Cities and ports

Let us note the more significant Russian port cities located in the Sea of Japan:

Vladivostok;
Nakhodka;
Oriental;
Sovetskaya Gavan;
Vanino;
Shakhtersk

Flora and fauna

Brown algae and kelp grow abundantly along the seashores. The Sea of Japan is very rich in fish fauna due to the abundance of oxygen and food. Approximately 610 species of fish live here. The main types of fish fauna are:

In the southern part of the sea - anchovy, sardine, horse mackerel, mackerel.
In the northern regions - flounder, herring, salmon, greenling, mussels, saury, hammerfish, tuna.

Fishing in the Sea of Japan lasts all year round. This region is home to 6 species of seals, 12 species of sharks that are not dangerous to humans, squid and octopuses.

Few people know the following Interesting Facts about the Sea of Japan:

Residents of North Korea call this sea the Korean East Sea;
Residents of South Korea - the East Sea.
Here you can meet representatives of 31 orders of fish out of 34 orders existing in the world;
The Sea of Japan leads in fish diversity among all the seas of the Russian Federation;
A small jellyfish lives in the algae of the sea, capable of infecting the central nervous system, and with repeated contact its poison can be fatal. There are no famous resorts here, but the Sea of Japan is very important for the trade and economy of several countries, including Russia.

Japanese Sea- a marginal sea of the Pacific Ocean, located between the mainland of Eurasia, the Korean Peninsula and the islands of Sakhalin, Hokkaido and Honshu. Countries washed by this sea are Russia, Japan, North Korea and South Korea. The Sea of Japan is one of the largest and deepest seas in the world. Its area is 1062 km 2, volume - 1631 thousand km 3, average depth - 1536 m, greatest depth - 3699 m. This is a marginal oceanic sea. There are no large islands in the Sea of Japan. Of the small ones, the most significant are the islands of Moneron, Rishiri, Okushiri, Ojima, Sado, Okinoshima, Ullyndo, Askold, Russky, and Putyatina. Tsushima Island is located in the Korea Strait. Almost all the islands are located near the coast. Most of them are located in the eastern part of the sea. The coastline of the Sea of Japan is relatively slightly indented. The simplest in outline is the coast of Sakhalin; the coasts of Primorye and the Japanese Islands are more winding.

Sailing

The study of the Sea of Japan in Russia began (by teams of the Great Northern, or Second Kamchatka, expedition of 1733-43) with the definition geographical location the islands of Japan and Sakhalin and partial photography of their shores. In 1806, surveys of the eastern coast of the Sea of Japan were carried out by the expedition of I. F. Krusenstern and Yu. F. Lisyansky during their circumnavigation of the world (1803-1806). The discovery in 1849 by G.I. Nevelsky of the strait between the mainland and the island was important. Sakhalin. Since 1880, a permanent Hydrographic Expedition began its work, ensuring the compilation of accurate navigation maps. Simultaneously with hydrographic work, observations of water temperature and surface currents were carried out. Extensive oceanographic work in the Pacific Ocean and Far Eastern seas began in 1888, with the voyage of S. O. Makarov on the corvette Vityaz. Makarov made careful deep-sea observations in the La Perouse Strait for the first time; Oceanographers still use this data to this day.

During World War II, the study of the sea was sporadic. After the war, especially with the arrival of the special expedition vessel of the Institute of Oceanology of the USSR Academy of Sciences “Vityaz”, research work in the Far Eastern seas reached enormous proportions.

Bottom relief

Based on the nature of the bottom topography, the Sea of Japan is divided into three parts: northern, central and southern. The northern part of the sea is a wide trench, gradually rising and narrowing towards the north. The central part of the sea is a deep closed basin, slightly elongated in the east-northeast direction. The southern part of the sea has a very complex topography with alternating troughs and relatively shallow areas. Here is the vast underwater rise of Yamato.

Climate and hydrological regime

The climate of the Sea of Japan is temperate, monsoonal. The northern and western parts of the sea are much colder than the southern and eastern. In the coldest months (January-February), the average air temperature in the northern part of the sea is about -20 o C, and in the south about +5 o C. The summer monsoon brings with it warm and humid air. The average air temperature of the warmest month (August) in the northern part is approximately +15 o C, in the southern regions about +25 o C. In autumn, the number of typhoons caused by hurricane winds increases. The largest waves have a height of 8-10 m, and during typhoons, the maximum waves reach a height of 12 m.

In winter, the temperature of surface waters from -1 to 0 o C in the north and northwest rises to +10-14 o C in the south and southeast. Spring warming entails a fairly rapid increase in water temperature throughout the sea. In summer, the surface water temperature rises from +18-20 o C in the north to +25-27 o C in the south of the sea. The salinity of the water in the Sea of Japan is 33.7-34.3‰, which is slightly lower than the salinity of the waters of the World Ocean. The tides in the Sea of Japan are distinct, to a greater or lesser extent in different areas. The greatest level fluctuations are observed in the extreme northern and extreme southern regions and reach 3 meters. The appearance of ice in the Sea of Japan is possible as early as October, and the last ice lingers in the north sometimes until mid-June. Every year, only the northern bays of the mainland coast freeze completely. In the western part of the sea, floating, stationary ice appears earlier than in the eastern part, and it is more stable.

Flora and fauna

The Sea of Japan is one of the most productive. Along the coast, algae form powerful thickets; The benthos is diverse and large in biomass. The abundance of food and oxygen, the influx of warm waters create favorable conditions for the development of fish fauna. The fish population of the Sea of Japan includes 615 species. Here you can find octopuses and squids - typical representatives warm seas. At the same time, vertical walls overgrown with sea anemones, gardens of brown algae - kelp - all this is reminiscent of the landscapes of the White and Barents Seas. In the Sea of Japan there is a huge abundance of starfish and sea urchins, of various colors and sizes, brittle stars, shrimps, and small crabs are found (Kamchatka crabs are found here only in May, and then they move further into the sea). Bright red ascidians live on rocks and stones. The most common shellfish is scallops. Among the fish, blennies and sea ruffes are often found. In the Sea of Japan you can find fur seals that come here for the winter from more northern regions, representatives of earless seals - seals, dolphins and even whales.

Economic importance

The Sea of Japan is characterized by high development of two industries. Fisheries combine fishing (sardine, mackerel, saury and other species) and the extraction of non-fish objects (sea shellfish - mussels, scallops, squid; algae - kelp, seaweed, ahnfeltia). The leading place in the species composition of fish catches is occupied by pollock, sardine and anchovy. Fishing in most parts of the sea continues all year round. In the Sea of Japan, active work is underway to breed mariculture - the most promising method of using marine biological resources. On the shores of the Sea of Japan, in Vladivostok, the Trans-Siberian Railway ends. The most significant transshipment transport hub is located here, where cargo is exchanged between rail and sea transport. Further along the Sea of Japan, cargo travels on sea vessels to various foreign and Russian ports, just as they arrive from other ports to the ports of the Sea of Japan: Nakhodka, Vanino, Aleksandrovsk-on-Sakhalin, Kholmsk. These ports provide maritime transport not only in the Sea of Japan, but also beyond it. Since the 1990s, the coast of the Sea of Japan off the coast of Primorye has begun to be actively developed by local and visiting tourists. The impetus was factors such as the abolition or simplification of visits to the border zone, rising costs passenger transportation around the country, which has done too much expensive vacation Far Easterners to Black Sea coast, as well as a greatly increased number of personal vehicles, which made the Primorye coast accessible to residents of Khabarovsk and the Amur region.

The resource base of minerals in the Russian part of the Sea of Japan is insignificant. The Izylmetyevskoe gas field was discovered on the West Sakhalin shelf of the sea, but it is unprofitable for exploitation. Promising areas with sand were identified on the continental shores of the sea.

Ecology

The Sea of Japan abounds in flora and fauna suitable for industrial production. Fishing fleets of states are actively fishing and extracting crabs, sea cucumbers, algae, sea urchin and scallop. At the same time, there are problems associated with it. The discrepancy between the amount of fish and shellfish caught and the volume of their natural restoration leads to the death and extinction of some of their species. The share of poaching in this is large. In addition, the fleet pollutes sea waters with waste fuels and lubricants, oil products, waste and sewage. This applies not only to fishing vessels, but also to the merchant and military fleets of the four powers. Nuclear fleet bases in the ports of the Sea of Japan, disposal and disposal of used radioactive substances and ships removed from combat duty require close attention and control.

The main source of pollution is the city of Vladivostok. Drains from its industrial enterprises, city sewerage, products economic activity ports and ship repair yards end up in the waters of the Amur and Ussuri Bays, and most of all in aquatic environment bays of the Golden Horn.

The Sea of Japan is a marginal sea of the Pacific Ocean and is limited by the coasts of Japan, Russia and Korea. The Sea of Japan is connected through the Korea Strait in the south with the East China and Yellow Seas, through the Tsugaru (Sangara) Strait in the East with the Pacific Ocean and through the La Perouse and Tatar Straits in the north with the Sea of Okhotsk. The area of the Sea of Japan is 980,000 km2, the average depth is 1361 m. The northern border of the Sea of Japan runs along 51 ° 45 "N latitude (from Cape Tyk on Sakhalin to Cape Yuzhny on the mainland). The southern border runs from the island of Kyushu to the Goto Islands and from there to Korea [Cape Kolcholkap (Izgunov)]

The Sea of Japan has an almost elliptical shape with the major axis in the direction from southwest to northeast. Along the coast there are a number of islands or island groups - these are the islands of Iki and Tsushima in the middle part of the Korean Strait. (between Korea and Kyushu Island), Ulleungdo and Takashima off the east coast of Korea, Oki and Sado off the west coast of Honshu Island (Hondo) and Tobi Island off the northwestern coast of Honshu (Hondo).

Bottom relief

The northern part has a relatively flat bottom topography and is characterized by an overall smooth slope. The maximum depth (4224 m) is observed in the area of 43°00"N, 137°39"E. d.
The bottom topography of the southern part of the Sea of Japan is quite complex. In addition to the shallow waters around the islands of Iki, Tsushima, Oki, Takashima and Ulleungdo, there are two large isolated
jars separated by deep grooves. This is the Yamato Bank, opened in 1924, in the area of 39°N, 135°E. etc., and the Shunpu Bank (also called the Northern Yamato Bank), opened in 1930 and located approximately 40° N. latitude, 134° east. d. The smallest depths of the first and second banks are 285 and 435 m, respectively. A depression with a depth of more than 3000 m was discovered between the Yamato Bank and the island of Honshu.

Hydrological regime

Water masses

The surface water mass exhibits the largest fluctuations in temperature and salinity depending on the season and region. Thus, in the Korea Strait, the salinity of surface waters in April and May exceeds 35.0 ppm. which is higher than the salinity in the deeper layers, but in August and September the salinity of surface waters drops to 32.5 ppm. At the same time, in the area of the island of Hokkaido, salinity varies only from 33.7 to 34.1 ppm. In summer surface water temperature 25°C, but in winter it varies from 15°C in the Korea Strait to 5°C near the island. Hokkaido. In the coastal areas of Korea and Primorye, changes in salinity are small (33.7-34 ppm). The intermediate water mass, which lies below the surface water in the warm sector of the Sea of Japan, has high temperature and salinity. It is formed in the intermediate layers of Kuroshio west of Kyushu Island and enters the Sea of Japan from there during the period of early winter to early summer.

Sometimes the low-salinity surface waters of the cold sector (1-4° C, 33.9 ppm) wedge into the polar front and deepen in a southerly direction, going under the intermediate waters of the warm sector. This phenomenon is similar to the penetration of subarctic intermediate water below the warm Kuroshio layer in the Pacific Ocean in the area north of Japan.

In spring and summer, the salinity of warm waters from the East China Sea and cold waters east of Korea decreases due to precipitation and melting ice. These less saline waters mix with surrounding waters and the overall salinity of the surface waters of the Sea of Japan decreases. Additionally, these surface waters gradually warm up during the warmer months. As a result, the density of surface waters decreases, which leads to the formation of a clearly defined upper thermocline layer that separates the surface waters from the underlying intermediate waters. The upper thermocline layer is located in the summer season at a depth of 25 m. In autumn, heat is transferred from the sea surface to the atmosphere. Due to mixing with underlying water masses, the temperature of surface waters decreases and their salinity increases. The resulting intense convection leads to a deepening of the upper thermocline layer to 25–50 m in September and 50–100 m in November. In autumn, intermediate waters of the warm sector are characterized by a decrease in salinity due to the influx of waters of the Tsushima Current with lower salinity. At the same time, convection in the surface water layer intensifies during this period. As a result, the thickness of the intermediate water layer decreases. In November, the upper thermocline layer disappears completely due to the mixing of overlying and underlying waters. Therefore, in autumn and spring there is only an upper homogeneous layer of water and an underlying cold layer, separated by a layer of lower thermocline. The latter for most of the warm sector is located at a depth of 200-250, but to the north it rises and off the coast of the island of Hokkaido is located at a depth of about 100 m. In the warm sector of the surface layer, temperatures reach a maximum in mid-August, although in the northern part of the Sea of Japan they spread to the depths. The minimum temperature is observed in February–March. On the other hand, the maximum surface layer temperature off the Korean coast is observed in August. However, due to the strong development of the upper thermocline layer, only a very thin surface layer is heated. Thus, temperature changes in the 50-100 m layer are almost entirely due to advection. Due to the low temperatures characteristic of most of the Sea of Japan at fairly large depths, the waters of the Tsushima Current are greatly cooled as they move north.

Surface and intermediate waters are most saturated with oxygen. The percentage of saturation in the warm sector is 100% or slightly lower, and the waters near Primorsky Krai and Korea are oversaturated with oxygen due to low temperatures. Near the northern coast of Korea it is 110% and even higher. In deep waters there is a very high oxygen content right down to the bottom.

Color and transparency

Currents of the Sea of Japan

The main current of the Sea of Japan is the Tsushima Current, which originates in the East China Sea. It is strengthened mainly by the branch of the Kuroshio Current, going to the SOUTHWEST of the island. Kyushu, as well as partially by coastal runoff from China. The Tsushima Current contains surface and intermediate water masses. The current enters the Sea of Japan through the Korea Strait and heads along the northwestern coast of Japan. There, a branch of the warm current, called the East Korean Current, separates from it, which goes in the north, to the coast of Korea, to the Korean Gulf and Ulleungdo Island, then turns to the SE and connects with the main flow.

The Tsushima Current, about 200 km wide, washes the shores of Japan and goes further to the NE at a speed of 0.5 to 1.0 knots. Then it divides into two branches - the warm Sangar Current and the warm La Perouse Current, which respectively exit into the Pacific Ocean through the Tsugaru (Sangarsky) Strait and into the Sea of Okhotsk through the La Perouse Strait. Both of these currents, after passing through the straits, turn east and go, respectively, near the eastern coast of the island of Honshu and the northern coast of the island of Hokkaido.

Tides and tidal currents

Tidal waves propagate at right angles to these cotidal lines. West of Sakhalin and in the area of the Korean Strait. two points of amphidromy are observed. A similar cotidal map can be constructed for the lunisolar diurnal tide. In this case, the amphidromy point is located in the Korea Strait. Since the total cross-sectional area of the La Perouse and Tsugaru Straits is only 1/8 of the cross-sectional area of the Korea Strait, and the cross-section of the Tartary Strait is generally insignificant, the tidal wave comes here from the East China Sea mainly through the East passage (Tsushima Strait). The magnitude of forced fluctuations in the mass of water in the entire Sea of Japan is practically negligible. The resulting component of tidal currents and the eastward Tsushima Current sometimes reaches 2.8 knots. In the Tsugaru (Soigarsky) Strait, a tidal current of the diurnal type predominates, but the magnitude of the semidiurnal tide is greater here.

Ice Conditions

Freezing of the Sea of Japan begins in mid-November in the area of the Tatar Strait and in early December in the upper reaches of Peter the Great Bay. In mid-December, areas near the northern part of Primorsky Krai and Peter the Great Bay freeze. In mid-December, ice appears in the coastal areas of Primorsky Krai. In January, the area of ice cover increases further from the coast towards the open sea. With the formation of ice, navigation in these areas naturally becomes difficult or stops. The freezing of the northern part of the Sea of Japan is somewhat delayed: it begins in early to mid-February.

Geology

The continental slopes of the Sea of Japan basin are characterized by many submarine canyons. On the mainland side, these canyons stretch to depths of more than 2000 m, and on the side of the Japanese Islands only to 800 m. The mainland shoals of the Sea of Japan are poorly developed, the edge runs at a depth of 140 m on the mainland side and at a depth of more than 200 m. Yamato Bank and other banks The Sea of Japan is composed of bedrock consisting of Precambrian granites and other Paleozoic rocks and overlying Neogene igneous and sedimentary rocks. According to paleogeographic studies, the southern part of the modern Sea of Japan was probably dry land in the Paleozoic and Mesozoic and during most of the Paleogene. It follows from this that the Sea of Japan was formed during the Neogene and early Quaternary periods. The absence of a granite layer in the earth's crust of the northern part of the Sea of Japan indicates the transformation of the granite layer into a basalt layer due to basification, accompanied by subsidence of the earth's crust. The presence of “new” oceanic crust here can be explained by the stretching of continents accompanying the general expansion of the Earth (Egayed’s theory).

The Sea of Japan currently has a connection with the Pacific Ocean and the surrounding marginal seas through the Korean, Tsugaru (Saigarsky), La Perouse and Tatar straits. However, the formation of these four straits occurred during very recent geological periods. The oldest strait is the Tsugaru (Sangara) Strait; it already existed during the Wisconsinian glaciation, although it may have been filled with ice several times after that and used in the migration of land animals. The Korea Strait was also dry land at the end of the Tertiary period, and through it the migration of southern elephants to the Japanese islands took place; this strait opened only at the beginning of the Wisconsin glaciation. The La Perouse Strait is the youngest. Fossilized remains of mammoths found on the island of Hokkaido indicate the existence of an isthmus. land on the site of this strait until the end of the Wisconsin glaciation

The East Korean Current is a branch of the Tsushima Current along the coast of Korea. A feature of the current is its separation from the shore, which is usually noticeable at 38° N. This branch of the Tsushima Current is more powerful than the other two. Warm waters transported north through it meet cold waters and form the Subarctic Front. Numerous vortices and jets depart from this branch, so that the interaction of cold subarctic and warm subtropical does not occur along a narrow line, but in a large frontal zone. 80-90% of its waters return to the south in the form of a countercurrent and only a small part of them penetrates to the north and northeast (mainly through eddies and jets). The salinity and concentration of dissolved oxygen in the waters transported by the East Korean Current are similar to those of the Tsushima Current waters (34.10-34.40 ‰ and less than 5 ml/l, respectively). The temperature, both in summer and winter, never falls below 12 °C. The highest current speed values were noted in the zone located between the 4-8 °C isotherms at a horizon of 100 m (Tanioka K., 1968). The average speed of the current is 9 cm/s, and the average width of the stream is 30 miles. But the characteristics of the flow are variable: for example, the volumetric transport by the current varies from 0.3 to 3.2 light. It is believed that the current speed is higher in summer (47 cm/s) than in winter (17 cm/s), and interannual variability is greater than intraannual variability (Shuto K., 1982).

The Primorsky Current is a flow of cold desalinated waters along the coast of the continent from the northern part of the Tatar Strait to Peter the Great Bay. Its origins are unclear. The characteristics of the Primorsky Current and the characteristics of the waters carried by it have never been specifically studied. The characteristics of its waters according to different sources are very contradictory. The most reliable information is about salinity (always less than 34.00 ‰), since the waters of the Tatar Strait have always been characterized by low salinity and high concentration of dissolved oxygen (usually more than 6.0 ml/l). It was noted (Hidaka K.) that “the cold currents of the Sea of Japan are significantly weaker than the warm ones.” Due to the fact that in the Sea of Japan they themselves warm currents are quite weak, the Primorye Current is most noticeable only in winter, when northern and northwestern winds prevail over Primorye. At this time, numerous jets move away from the current (Istoshin Yu.V., 1950).

The North Korean Current is a southward flow of cold input from Peter the Great Bay, at least to 38° N. latitude. Due to the fact that this current is artificially separated from the Primorsky current, the area of its formation is only conditionally assigned to the Peter the Great Gulf. Often this current is not particularly noticeable. The current is located in the exclusive economic zone North Korea, therefore, the special conditions of oceanographic work have determined its extremely low oceanographic knowledge. For these reasons, very little is known about this current. M. Uda noticed that the North Korean Current is stronger than the Primorsky Current. The width of this current, according to M. Uda’s calculations, is 100 km, the thickness of the layer it transports is 50 m, and the average speed is 25 cm/sec.

The Tsushima Current is a flow of warm and salty subtropical waters from the Tsushima Strait in the south to the middle of the Tatar Strait in the north. The warm waters of the Yellow Sea also take part in the formation of its waters, but it is usually considered only as a branch of the Kuroshio, separated from the main flow in the area of the island. Kyushu. Its waters differ from surrounding waters primarily in their high (more than 34.3 ‰) salinity. The core of the current is usually traced around the 100 m horizon. This current is weak compared to Kuroshio. His speed is, on average, 20 times less than Kuroshio's speed. The average transport (across the Tsushima Strait) is about 2 sv, but it is thought to vary throughout the year from a minimum (less than 1 sv) in February to a maximum in August (more than 5 sv). Due to its low speed, the current strongly meanders, separating warm eddies, branches and jets. Two main branches of the current are visible already in the strait. The transfer ratio in the western and eastern parts of the strait is, according to K. Naganuma, 3:1. Despite the fact that the current is sometimes presented as meandering, it is usually represented as consisting of two branches: along the coast of Japan (Tsushima Current), along the coast of Korea (East Korean Current). Sometimes another (nameless) branch is identified between them. Approximately at 38°N. the second branch breaks away from the shore. Despite the fact that the reason for the separation of the Kuroshio and the East Korean Current is the same (the uneven rotation of the Earth at different latitudes), the latitude of the separation of the East Korean Current exceeds the latitude of the Kuroshio separation by hundreds of kilometers. Flow branches do not always exist simultaneously. For example, in 1973, the first branch was observed only in the summer (from March to August), the second - from June to August, and only the third usually exists throughout the year (although seasons and years are known when it was absent). The first branch penetrates the sea only through the eastern part of the Tsushima Strait, and the other two - through the western. The temperature of the water carried by the current decreases from 28 °C in summer (14 °C in winter) in the Tsushima Strait to 17 °C (8 °C) in the Hokkaido region. The concentration of dissolved oxygen in the subtropical waters of the current never exceeds 5.0 ml/l, and the conditional density is 27.20.

Sea of Japan, features of tourism. Currents in the Sea of Japan The Sea of Japan is warm

Hydrological regime

Currents of the Sea of Japan

Tides and tidal currents

Ice Conditions

Origin

Historical events

Characteristic

Currents

What rivers flow into

Where does the Sea of Japan flow into?

Climate

Relief

Cities and ports

Flora and fauna

Sailing

Bottom relief

Climate and hydrological regime

Flora and fauna

Economic importance

Ecology

Hydrological regime

Currents of the Sea of Japan

Tides and tidal currents

Ice Conditions

Latest

You need to know this

Sea of ​​Japan, features of tourism. Currents in the Sea of ​​Japan The Sea of ​​Japan is warm

Hydrological regime

Currents of the Sea of ​​Japan

Tides and tidal currents

Ice Conditions

Origin

Historical events

Characteristic

Currents

What rivers flow into

Where does the Sea of ​​Japan flow into?

Climate

Relief

Cities and ports

Flora and fauna

Sailing

Bottom relief

Climate and hydrological regime

Flora and fauna

Economic importance

Ecology

Hydrological regime

Currents of the Sea of ​​Japan

Tides and tidal currents

Ice Conditions

Latest

You need to know this

Sea of Japan, features of tourism. Currents in the Sea of Japan The Sea of Japan is warm

Currents of the Sea of Japan

Where does the Sea of Japan flow into?

Currents of the Sea of Japan