16.11.2007 13:52

Current is the movement of water particles from one place in the ocean or sea to another.

Currents cover huge masses of ocean water, spreading in a wide strip on the surface of the ocean and capturing a layer of water of varying depth. At greater depths and near the bottom, there are slower movements of water particles, most often in the opposite direction compared to surface currents, which is part of the general water cycle of the World Ocean.

The main forces causing sea currents are determined by both hydrometeorological and astronomical factors.

The first should include:

1) density force or driving force of currents created by density differences due to uneven changes in temperature and salinity of sea water

2) the slope of sea level caused by excess or lack of water in a particular area, due to, for example, coastal runoff or wind surges and surges

3) sea level tilt caused by changes in the distribution of atmospheric pressure, creating a decrease in sea level in areas of high atmospheric pressure and a rise in levels in areas of low pressure

4) wind friction on the surface of the sea waters and wind pressure on the rear surface of the waves.

The second ones include tidal forces of the Moon and the Sun, continuously changing due to periodic changes in the relative positions of the Sun, Earth and Moon and creating horizontal fluctuations of water masses or tidal currents.

Immediately after the occurrence of a flow caused by one or more of these forces, secondary forces arise that influence the flow. These forces are incapable of causing currents; they only modify the current that has already arisen.

These forces include:

1) the Coriolis force, which deflects any moving body to the right in the northern hemisphere, and to the left in the southern hemisphere from the direction of its movement, depending on the latitude of the place and the speed of movement of the particles

2) friction force, slowing down any movement

3) centrifugal force.

Sea currents are divided according to the following characteristics:

1. By origin, i.e. according to the factors that cause them - a) density (gradient) currents; b) drift and wind currents; c) waste or runoff currents; d) barogradient; e) tidal; f) compensatory currents, which are a consequence of the almost complete incompressibility of water (continuity), arise due to the need to compensate for the loss of water, for example, from the wind driving water or its outflow due to the presence of other currents.

2. By region of origin.

3. By duration or stability: a) constant currents flowing from year to year in the same direction at a certain speed; b) temporary currents caused by transient causes and changing their direction and speed depending on the time of action and the magnitude of the generating force; c) periodic currents that change their direction and speed in accordance with the period and magnitude of tidal forces.

4. According to physical and chemical characteristics, for example, warm and cold. Moreover, the absolute value of temperature does not matter for the flow characteristics; the temperature of the waters of warm currents is higher than the temperature of the waters created by local conditions, the temperature of the waters of cold currents is lower.

Main currents in the Pacific Ocean influencing the climate of Primorye

Kuroshio (Kuro-Shio) The Kuroshio system is divided into three parts: a) Kuroshio proper, b) Kuroshio drift and c) North Pacific Current. Kuroshio proper is the area of ​​warm current in the western part of the northern half Pacific Ocean between Taiwan Island and 35°N, 142°E.

The beginning of Kuroshio is the branch of the North Trade Wind Current, running north along the eastern shores Philippine Islands. Near the island of Taiwan, Kuroshio has a width of about 185 km and a speed of 0.8-1.0 m/s. Then it deviates to the right and runs along western shores island ridge of Ryukyu, and the speed at times increases to 1.5-1.8 m/s. An increase in Kuroshio speeds usually occurs in summer with tailwinds of the summer southeast monsoon.

On the approaches to the southern tip of Kyushu Island, the current splits into two branches: the main branch passes through Van Diemen's Strait to the Pacific Ocean (Kuroshio proper), and the other branch goes to Korea Strait(Tsushima Current). Kuroshio itself, when approaching the southeastern tip of the island of Honshu - Cape Najima (35° N, 140° E) - turns to the east, being pushed away from the coast by the cold Kuril Current.

At a point with coordinates 35°N, 142°E. Two branches separate from Kuroshio: one goes south and the other goes northeast. This last branch reaches far to the north. Traces of the northeastern branch can be observed up to Commander Islands.

The Kuroshio drift is the section of warm current between 142 and 160°E, after which the North Pacific Current begins.

The most stable of all three components of the Kuroshio system is the Kuroshio current itself, although it is subject to large seasonal fluctuations; so in December, during greatest development With the winter monsoon blowing from the north or northwest, where Kuroshio is usually located, ships often note southward currents. This indicates the great dependence of the current on the monsoon winds, which are very strong and constant off the eastern coast of Asia.

The influence of Kuroshio on the climate of coastal countries East Asia such that the warming of waters in the Kuroshio region causes an exacerbation of the winter monsoon in winter.

. Kuril Current

The Kuril Current, sometimes called the Oya Sio, is a cold current. It originates in the Bering Sea and flows first south under the name Kamchatka Current along the eastern shores of Kamchatka, and then along the eastern shores of the Kuril ridge.

IN winter time through the straits Kuril ridge(especially through its southern straits) masses enter the Pacific Ocean from the Sea of ​​Okhotsk cold water, and sometimes ice, which greatly enhances Kuril Current. In winter, the speed of the Kuril Current fluctuates around 0.5-1.0 m/s, in summer it is slightly less - 0.25-0.35 m/s.

The cold Kuril Current flows first along the surface, penetrating south a little further than Cape Nojima - the southeastern tip of the island of Honshu. The width of the Kuril Current at Cape Nojima is about 55.5 km. Soon after passing the cape, the current descends under the surface waters of the ocean and continues for another 370 km as an underwater current.

Main currents in the Sea of ​​Japan

The Sea of ​​Japan is located in the northwestern Pacific Ocean between the mainland coast of Asia, Japanese islands And Sakhalin Island V geographical coordinates 34°26"-51°41" N, 127°20"-142°15" E According to its physical and geographical position, it belongs to the marginal oceanic seas and is fenced off from adjacent basins by shallow barriers.

In the north and northeast, the Sea of ​​Japan is connected to the Sea of ​​Okhotsk by the Nevelskoy and La Perouse (Soya) straits, in the east - with Pacific Ocean, Sangar (Tsugaru) Strait, in the south - from East China Sea Korea (Tsushima) Strait. The smallest of them is the strait- Nevelskogo has a maximum depth of 10 m, and the deepest Sangarsky- about 200 m.

The greatest influence on the hydrological regime of the basin is exerted by subtropical waters entering through Korea Strait from the East China Sea. The movement of water in the Sea of ​​Japan is formed as a result of the total effect of the global distribution of atmospheric pressure, wind field, heat and water flows. In the Pacific Ocean, isobaric surfaces tilt toward the Asian continent with a corresponding transfer of water. The Sea of ​​Japan from the Pacific Ocean receives mainly the waters of the western branch of the warm Kuroshio, passing through the East China Sea and adding its waters.

Due to the shallowness of the straits, only surface water enters the Sea of ​​Japan. Every year, from 55 to 60 thousand km3 of warm water enters the Sea of ​​Japan through the Korean Irrigation. The stream of these waters in the form Tsushima Current changes throughout the year. It is most intense at the end of summer - beginning of autumn, when, under the influence of the southeast monsoon, the western branch of Kuroshio strengthens and water surges into East China Sea. During this period, the water inflow increases to 8 thousand km3 per month. At the end of winter, the influx of water into the Sea of ​​Japan through the Korean Irrigation decreases to 1.5 thousand km3 per month. Due to the passage of the Tsushima Current off the western coast of the Japanese Islands, sea level here is on average 20 cm higher than in the Pacific Ocean off the eastern coast of Japan. Therefore, already in the Sangar Strait, the first along the path of the waters of this current, there is an intense flow of water into the Pacific Ocean.

Approximately 62% of the waters of the Tsushima Current leave through this strait, as a result of which it then becomes greatly weakened. Another 24% of the volume of water coming from the Korea Strait flows through the La Perouse Strait and further north it flows warm waters becomes extremely insignificant, but still an insignificant part of the waters Tsushima Current penetrates into the summer Strait of Tartary. In it, due to the small cross-section of the Nevelskoy Strait, most of these waters turn south. As the flow of water in the Tsushima Current moves north, water from other currents is included in it and jets are diverted from it. In particular, the jets that deviate to the west in front of the Tatar Strait merge with the waters leaving it, forming a stream flowing at low speed to the south. Primorsky Current.

South of Peter the Great Bay, this current divides into two branches: the coastal one continues to move south and, in part in separate jets, together with the return waters of the Tsushima Current in eddy gyres, exits into Korea Strait, and the eastern jet deviates to the east and connects with the Tsushima Current. The coastal branch is called the North Korean Current.

The entire listed system of currents forms a cyclonic circulation common to the entire sea, in which the eastern periphery consists of a warm current, and the western periphery consists of a cold one.

Temperature distribution and velocity on the surface of the Sea of ​​Japan are presented according to the electronic Atlas of Oceanography of the Bering, Okhotsk and Japan Seas (POI FEB RAS) for January, March, May, July, September, October.

Current speeds in the southern half of the sea are higher than in the northern half. Calculated by the dynamic method they are in the upper 25 meter layer Tsushima Current decrease from 70 cm/s to Korea Strait up to approximately 29 cm/s at the latitude of the La Perouse Strait and become less than 10 cm/s at Tatar Strait. The speed of the cold current is significantly lower. It increases to the south from several centimeters per second in the north to 10 cm/s in the southern part of the sea.

In addition to constant currents, drift and wind currents are often observed, which cause surges and surges of water. There are cases when the total currents, composed mainly of constant, drift and tidal currents, are directed at right angles to the shore or away from the shore. In the first case, they are called pressing, in the second, squeezing. Their speed usually does not exceed 0.25 m/s.

Water exchange through the straits has a dominant influence on the hydrological regime of the southern and eastern half of the Sea of ​​Japan. Flowing through Korea Strait The subtropical waters of the Kuroshio branch throughout the year warm the southern regions of the sea and the waters adjacent to the coast of the Japanese Islands up to the La Perouse Strait, as a result of which the waters of the eastern part of the sea are always warmer than the western.

Literature: 1. Doronin Yu. P. Regional oceanology. - L.: Gidrometeoizdat, 1986.

2. Istoshin I.V. Oceanology. - L.: Gidrometeoizdat, 1953.

3. Sea of ​​Japan pilotage. Part 1, 2. - L.: Navy Cart Factory, 1972.

4. Atlas of oceanography of the Bering, Okhotsk and Japan seas (POI FEB RAS). - Vladivostok, 2002

Head of OGMM
Yushkina K.A.

Sea of ​​Japan- 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 the detachments of the Great Northern, or Second Kamchatka, expedition of 1733-43) by determining the geographical location of the islands of Japan and Sakhalin and partially photographing their coasts. In 1806, surveying of the eastern coast of the Sea of ​​Japan was carried out by the expedition of I. F. Kruzenshtern and Yu. F. Lisyansky during their circumnavigation(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 Patriotic War exploration 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. Northern part The sea is a wide trench, gradually rising and narrowing to 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 is very different difficult terrain with alternating trenches 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. Average temperature the air 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. Most large waves have a height of 8-10 m, and during typhoons the maximum waves reach a height of 12 m.

Winter temperature surface waters from -1 to 0 o C in the north and northwest it 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 of 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, different colors And different 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, sea kale, ahnfeltia). The leading place in the species composition of fish catches is occupied by pollock, sardine and anchovy. Fishing continues in most of the sea all year round. In the Sea of ​​Japan there are active work for mariculture breeding - 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 across the Sea of ​​Japan, but also beyond. 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 visiting the border zone, the rise in the cost of passenger transportation around the country, which made it too expensive for Far Easterners to vacation on the Black Sea coast, as well as the 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 wastewater. 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. Drain it 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 the aquatic environment of the Golden Horn Bay.

Currents of the Sea of ​​Japan They are distinguished by a noticeable variety of regimes, which determines the formation of mixed warm-water and temperate flora and fauna on the shores of the sea, despite quite clear zonal differences between the northwestern and southeastern parts of its water area.

General characteristics

Generally, surface currents in the sea are cyclonic in nature and directed counterclockwise. The warm vector, represented by the Tsushima Current, moves along the island. Honshu to the north. The cold current comes from the Tartary Strait and passes along the coast of the mainland to the south. Each of them has large and small branches. In addition, in the inner part of the water area, up to five mixed circulation zones are distinguished, which are large whirlpools. Currents, divided into cold and warm, have the following names:

Peculiarities

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An excerpt characterizing the Currents of the Sea of ​​Japan

Soon after the return of Prince Andrei, the old prince separated his son and gave him Bogucharovo, a large estate located 40 miles from Bald Mountains. Partly because of the difficult memories associated with the Bald Mountains, partly because Prince Andrei did not always feel able to bear his father’s character, and partly because he needed solitude, Prince Andrei took advantage of Bogucharov, built there and spent most of his time there. time.
Prince Andrei, after the Austerlitz campaign, firmly decided never to serve again in military service; and when the war began, and everyone had to serve, he, in order to get rid of active service, accepted a position under his father in collecting the militia. The old prince and his son seemed to change roles after the 1805 campaign. The old prince, excited by the activity, expected all the best from the real campaign; Prince Andrei, on the contrary, not participating in the war and secretly regretting it in his soul, saw only one bad thing.
On February 26, 1807, the old prince left for the district. Prince Andrei, as for the most part during his father’s absences, remained in Bald Mountains. Little Nikolushka had been unwell for the 4th day. The coachmen who drove the old prince returned from the city and brought papers and letters to Prince Andrei.
The valet with letters, not finding the young prince in his office, went to Princess Marya’s half; but he wasn’t there either. The valet was told that the prince had gone to the nursery.
“Please, your Excellency, Petrusha has come with papers,” said one of the nanny’s assistant girls, turning to Prince Andrei, who was sitting on a small children's chair and with trembling hands, frowning, he dripped medicine from a glass into a glass half filled with water.
- What's happened? - he said angrily, and carelessly shaking his hand, he poured an extra amount of drops from the glass into the glass. He threw the medicine out of the glass onto the floor and asked for water again. The girl handed it to him.
In the room there was a crib, two chests, two armchairs, a table and a children's table and chair, the one on which Prince Andrei was sitting. The windows were curtained, and one candle was burning on the table, covered with a bound book of music, so that the light would not fall on the crib.
“My friend,” Princess Marya said, turning to her brother from the crib where she stood, “it’s better to wait... after...
“Oh, do me a favor, you keep talking nonsense, you’ve been waiting for everything - so you’ve waited,” said Prince Andrei in an embittered whisper, apparently wanting to prick his sister.
“My friend, it’s better not to wake him up, he fell asleep,” the princess said in a pleading voice.
Prince Andrei stood up and, on tiptoe, approached the crib with a glass.
– Or definitely not to wake you up? – he said hesitantly.
“As you want, right... I think... as you wish,” said Princess Marya, apparently timid and ashamed that her opinion had triumphed. She pointed out to her brother the girl who was calling him in a whisper.

Currents of the Sea of ​​Japan They are distinguished by a noticeable variety of regimes, which determines the formation of mixed warm-water and temperate flora and fauna on the shores of the sea, despite quite clear zonal differences between the northwestern and southeastern parts of its water area.

General characteristics

In general, surface currents in the sea are cyclonic in nature and directed counterclockwise. The warm vector, represented by the Tsushima Current, moves along the island. Honshu to the north. The cold current comes from the Tartary Strait and passes along the coast of the mainland to the south. Each of them has large and small branches. In addition, in the inner part of the water area, up to five mixed circulation zones are distinguished, which are large whirlpools. Currents, divided into cold and warm, have the following names:

Peculiarities

Notes

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• Prandtl Current
• Techenskoe rural settlement

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Currents of the Sea of ​​Japan

Tides in the Sea of ​​Japan

In different areas of the sea the tides are expressed differently, they are especially distinct in summer period and reach up to three meters in the Korea Strait. To the north, the tides decrease and do not exceed 1.5 m. This is explained by the fact that the bottom has a funnel shape. The greatest fluctuations are observed in the northern and southern extreme regions of the sea in the summer.

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