Part of the Pacific Ocean basin and separated from it by Sakhalin and the Japanese Islands, the Sea of Japan splashes off the coasts of Russia, Japan, China and Korea. The climatic conditions here are harsh. In the northern and western parts, ice appears already by the third ten days of November, and in some years the ice formed by the 20th of October. Temperatures in these areas can drop to -20 degrees Celsius. Ice melting begins in March and continues until the end of April. There were years when the sea surface was completely cleared of ice cover only in June.
However, in summer the Sea of Japan in its southern borders pleases with a water temperature of +27 (even higher than in the Aegean Sea!). In the northern part, the water temperature is about +20 degrees, the same as in May in the south of Greece. A characteristic feature of the Sea of Japan is its extremely unstable weather. In the morning the sun can shine brightly, and by lunchtime a strong wind rises and a storm with thunderstorms begins. This happens especially often in the fall. Then during a storm the wave can reach 10-12 meters in height.
The Sea of Japan is rich in fish. Mackerel, flounder, herring, saury, and cod are caught here. But the most popular, of course, is pollock. During spawning, coastal waters literally boil with a huge amount of this fish. They also produce shrimp and seaweed, which has become very popular in recent years, or rather, in addition, in the Sea of Japan you can find squid and octopus, which can be found weighing up to 50 kilograms. And the huge eels found here, also called herring kings, were in years past mistaken for underwater monsters.
Holidays on the Sea of Japan will appeal more to those who are not looking for noisy entertainment. The beauty of the reefs and crystal clear waters are ideal for snorkeling enthusiasts. Equipment here can be obtained from special diving centers. They also give it out at many tourist centers.
The only thing divers need to take into account is that the water temperature drops sharply with depth. In the northern waters, already at a depth of 50 meters it reaches only +4 degrees Celsius. In the southern part, the temperature reaches this level at a depth of approximately 200 meters. And a little deeper it equals zero.
Those who choose the Sea of Japan for vacation can not only go diving, but also make interesting forays into the Ussuri taiga. It keeps a lot of secrets and mysteries, so you won’t be bored here. Just look at the footprint of a giant left in a stone. Its length is incredible for our perception - it is one and a half meters! The Dragon Park is also of great interest. Local residents are sure that the unusual pile of huge boulders was once created by aliens. On the sea coast near the city of Nakhodka there are two hills called Brother and Sister. According to legend, they were made by the Titans as a gate through which the Prince of Light would one day come to Earth. For lovers of everything mysterious and unusual, a holiday on the Sea of Japan will seem like paradise. And the exotic beauty of these places will remain in the memory for a long time.
The Inland Sea of Japan splashes between Kyushu and Shikoku. It is small, only 18 thousand square kilometers, but is the most important transport artery between these islands. On its banks rise Hiroshima, Fukuyama, Osaka, Niihama and other major industrial centers of Japan. This sea is considered warm. The water temperature here, even in the winter months, never falls below +16 degrees Celsius, and in the summer it rises to +27. Tourism on this small sea is very well developed. Every year thousands of people from all over the world come here to admire the magnificent landscapes, visit ancient samurai shrines, and get acquainted with the original Japanese culture.
And the Japanese islands are the boundaries separating the waters of the Sea of Japan from the Pacific basin. The Sea of Japan predominantly has natural boundaries, only some areas are separated by conventional lines. The Sea of Japan, although it is the smallest of the Far Eastern seas, belongs to the largest. The water surface area is 1062 thousand km2, with a water volume of about 1630 thousand km3. The average depth of the Sea of Japan is 1535 m, the maximum depth is 3699 m. This sea belongs to the marginal oceanic seas.
A small number of rivers carry their waters into the Sea of Japan. The largest rivers are: Rudnaya, Samarga, Partizanskaya and Tumnin. Mostly all of this. During the year it is about 210 km 3 . Throughout the year, fresh water flows evenly into the sea. In July, river flow reaches its maximum. Water exchange between and the Pacific Ocean occurs only in the upper layers.
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 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. 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, 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 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.
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 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.
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. 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
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 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.
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 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.
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 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.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, 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).
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 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 Sea of Japan is characterized by a huge abundance of grasses and algae. In Peter the Great Bay alone, there are more than 200 species of them. These are mainly seaweed and kelp. Sea kale is used for food purposes, which is why it is not only collected in natural areas, but also grown on special plantations. The higher types of herbs include phyllospadix and zoster, which are also numerous in these waters.
The fauna is also very diverse. So, in addition to seals and whales, .
Found in the Sea of Japan and.
The most numerous inhabitants of the Sea of Japan:
Sea anemones
Experienced scuba divers have a wonderful opportunity to admire sea anemones. These are primitive living creatures, close relatives of corals.
Ascidia
While observing the underwater landscape of the bays, you can often find ascidian. Their height is 25 cm.
Shrimps
All kinds of shrimp and crustaceans are found in algae and marine plants at any time of the year. The most famous of them is the grass shrimp. Some of these crustaceans can grow up to 18 cm in length. Juveniles are emerald in color.
Sea cucumbers
Primorsky Krai is famous for its large number of sea cucumbers. There are many of these animals in the Far East and Southeast Asia. They are often called sea ginseng. The habitat of sea cucumbers is rocky placers, boulders and zoster thickets. They feed on microscopic organisms that live on soil particles. Scientists have discovered that the biological active substances secreted by sea cucumbers have antimicrobial and pharmacological effects. Japanese Cucumaria is very similar to sea cucumber. It lives in all Far Eastern seas, but at greater depths than the latter.
Starfish and sea urchins
Species of marine invertebrates include starfish and urchins. Flat urchins are inhabitants of the sandy bottom covered with dark purple hair, while round urchins are the main representatives of the coastal fauna of Primorye. The urchin fishery is extremely developed, as their caviar is a popular delicacy in Asia.
The skeleton of starfish contains calcium carbonate, hence its unusual appearance. In the Sea of Japan there is, for example, the Amur Star, which reaches 32 cm in diameter and moves at a speed of 10 cm per minute. Just like the Patiriya star, which can easily be found in the coastal zone after a storm, the Amur star feeds on sluggish mollusks or mollusks attached to stones.
Oysters, mussels and other shellfish
Adult oysters and mussels lead a sedentary lifestyle. Thanks to special threads, frequent inhabitants of shallow waters - Pacific mussels - are able to stay on the stone even when struck by waves and strong gusts of wind. Only a high level of fertility saves them from complete destruction by mollusks, stars and fish.
Mussels are excellent natural filters and help cleanse coastal waters. But on the other hand, they cause a lot of problems, because... hydraulic structures and ships are overgrown with them. The largest mussels live about 100 years and grow up to 20 cm in length. Their meat has good taste and contains useful substances. But you should be careful - mussels grown in environmentally unfavorable areas can accumulate microorganisms harmful to humans.
In the desalinated waters of the bays of the Far East of Russia, China, Japan, and Korea, you can find the giant Pacific oyster. It lives at depths of up to 7 meters. The size of the shell of this mollusk reaches 70 cm. The giant oyster can withstand both winter under ice and the sun's rays at low tides. At the end of summer in Peter the Great Bay you can see oysters spawning. The female throws out up to 100 million microscopic eggs, which together look like a small cloudy cloud. Then the eggs develop into larvae and float in the water for about a month, being transported over long distances by currents. Then the larvae sink to the bottom in search of a place to live. Having found a suitable underwater object, they firmly attach themselves to it.
Scallop farming in the Sea of Japan is of great industrial importance. This mollusk moves due to the flow of water when the valves are abruptly closed.
Kamchatka crab Kamchatka crab
Another common inhabitant of the local waters is the Kamchatka crab. It can be found from the Korean Peninsula to the Bering Strait, as well as along the American coast at depths of up to 270m. The span of its claws reaches 150 cm. Kamchatka crab is especially numerous off the coast of Western Kamchatka, where its main fishery is concentrated. The crab feeds mainly on various small mollusks, crustaceans, and worms. In spring, shoals of king crab approach the shores to breed.
Cephalopods
There is active fishing for octopus and squid in the Sea of Japan. One of the largest species of cephalopods, the giant octopus, is also found here. An adult weighs about 50 kg and reaches 3 meters in length (including tentacles). Giant octopuses live mainly in underwater grottoes, under rocks. They can also be found among piles of stones. Small specimens are found in the empty shells of large mussels. Octopuses feed on fish, shellfish, and crabs. In case of danger, the octopus releases ink liquid for camouflage and changes its color. They are often encountered by divers. Octopuses can stick to a suit or to the skin of a scuba diver with their suction cups on their tentacles, but they do not cause much harm to humans.
Fishes of the Sea of Japan
The Primorsky region is famous for its rich variety of fish. About 900 species of fish live in the Sea of Japan. Of these, 179 species are commercially available. The permanent inhabitants of these waters are pollock, Far Eastern salmon, cod, flounder, navaga, sea chanterelles, and sculpin gobies. In summer, off the coast of Primorye you can find warm-water fish such as mackerel, herring, saury, anchovy, garfish, and half-snout. Quite exotic species also swim into the Sea of Japan. For example: swordfish, sunfish, pufferfish, saberfish, flying fish, hammerhead shark, red barracuda and hedgehogfish.
Among the permanent inhabitants of seaside waters there are also interesting-looking fish. Seahorses, pipefish, various mollusks, butterfly fish, and sea cockerels swim in the coastal thickets. At the bottom of the sea live bright chanterelles - agonomala, golden ruffs.
There are 12 species of sharks living in the Sea of Japan, the most common of which is the Katran shark. The sharks here are not big and are not dangerous to humans.
Jellyfish
Jellyfish have long been used as a food item in Thailand, Japan, Korea, Malaysia, Indonesia and the Philippines. Ropilema jellyfish is considered one of the most valuable delicacies. However, to prepare it, you need to spend a lot of time (about a month) and effort. In addition, in China, jellyfish are used in medicine (in the treatment of tracheitis and changes in blood pressure).
Fauna of the Sea of Japan
About 30 species of seals, dolphins and whales live in the Sea of Japan. There is no permanent whale fishery here. But during the Second World War, minke whales were caught in Peter the Great Bay. All species of this family are present in the Sea of Japan. Among them: sei whale, blue whale, gray whale, humpback whale, southern right whale, fin whale and minke whale.
In addition, there are many species of odontocetes. Among them: sperm whale, white-winged porpoise, northern swimmer, beluga whale, Pacific white-sided dolphin, killer whale. However, in our times the number of these animals is less than at the beginning of the twentieth century. The populations of minke whales and gray whales have declined greatly. However, in recent decades, the number of cetaceans has begun to recover as intensive whaling has been abolished. Rare species of dolphins and whales can increasingly be observed off the coast of Primorye and in Peter the Great Bay.
Six species of seals live in the waters of the Sea of Japan. Among them: sea hare, sea lion, northern fur seal, akiba, sealed seal and lionfish.
The Sea of Japan is one of the largest and deepest seas in the world. Its area is 1062 km2, its volume is 1631 thousand km3, and its greatest depth is 3720 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, Rebun, Rishiri, Okushiri, Sado, and Ulleungdo.
The coastline of the Sea of Japan is relatively slightly indented. The simplest in outline is the coast of Sakhalin Island; the coasts of Primorye and the Japanese Islands are more winding. The large bays of the mainland coast include the following bays: Olga, Peter the Great, East Korean, Ishikari.
A distinctive feature of the Sea of Japan is the relatively small number of rivers flowing into it. Almost all rivers are mountainous. The continental flow into the Sea of Japan, equal to approximately 210 km3 per year, is fairly evenly distributed throughout the year.
The main role in the water balance of the sea is played by water exchange through the straits.
The straits vary in length, width and, most importantly, depth, which determines the nature of water exchange in the Sea of Japan. Through the Tsugari (Sangara) Strait, the Sea of Japan communicates directly with. The Nevelskoy and La Perouse straits connect the Sea of Japan with the Sea of Okhotsk, and the Korean Strait with. Due to the shallow depths of the straits and the great depths of the sea itself, conditions are created for isolating its deep waters from the Pacific Ocean and adjacent seas, which is the most important natural feature of the Sea of Japan.
The coast of the Sea of Japan, varied in structure and external forms in different areas, belongs to different morphometric types of coasts. These are predominantly abrasive shores, mostly little changed by the sea. To a lesser extent, the sea is characterized by shores. In some places, single rocks - kekurs - characteristic formations of the Sea of Japan coast rise from the water. Low-lying shores are found only on certain sections of the coast.
The winter monsoon brings dry and cold air to the Sea of Japan, the temperature of which increases from south to north and from west to east. In the coldest months - January and February - the monthly average in the north is about –20°С, and in the south about –5°С.
In warm seasons, the sea is affected by the Hawaiian High, and therefore southern and southwestern winds predominate. In summer and early autumn (July–October), the number of typhoons over the sea increases (with a maximum in September), which cause. The average monthly temperature of the warmest month of August is approximately 15°C in the northern part of the sea, and about 25°C in the southern regions.
The circulation of the waters of the Sea of Japan is determined by the influx of Pacific waters through the straits and the circulation over the sea itself. Warm currents in the eastern part of the sea and cold currents passing along its western shores form two cyclonic gyres in the northern and southern parts of the sea.
Water masses are divided into surface, intermediate and deep. The surface mass exhibits the largest temperature fluctuations in both time and space. In summer, the temperature of surface waters in the south is 24–25°C, in winter it varies from 15°C in the Korea Strait to 5°C off the island of Hokkaido. In the northwestern part of the sea, summer temperatures are 13–15°C, and in winter, throughout the convection layer, 0.2–0.4°C. The salinity of surface waters in summer in the south is 33.0–33.4‰, in the north it is about 32.5‰. In winter, in the northwestern part of the sea, salinity increases to 34.0–34.1‰. The intermediate zone has high temperature and salinity. The deep water mass has an extremely uniform temperature (0–0.5°C) and salinity (34.0–34.1‰).
Tidal fluctuations in the level of the Sea of Japan are small and amount to 0.2 m off the coast, 0.4–0.5 m off the coast of the Primorsky Territory, and only in the Korean and Tatar Straits exceed 2 m. The speeds of tidal currents are high only in the straits and can reach 140 cm /With.
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. The ice cover reaches its greatest development around mid-February. In the eastern part of the sea, ice melting begins earlier and occurs more intensely than at the same latitudes in the west.
Ice cover in the Sea of Japan varies significantly from year to year. There may be cases when the ice cover in one winter is 2 times or more greater than the ice cover in another.
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. The main commercial species of the southern part of the sea include sardines, anchovies, mackerel, and horse mackerel. In the northern regions, mainly mussels, flounder, herring, greenling and salmon are caught. In summer, tuna, hammerfish, and saury penetrate into the northern part of the sea. 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.
It is polluted by wastewater from cities, industrial enterprises and agricultural complexes located on the western coast of Sakhalin Island (area of the city of Aleksandrovsk-Sakhalinsky) and on the mainland (Khabarovsk Territory).
