The Sea of Japan is a volatile political region that is constantly patrolled



  The Sea of Japan, map in relation to Korea, China, Russia and the Pacific Ocean


Map of the Sea of Japan





While not strictly a matter to do with the Sea of Japan, a powerful typhoon lashed the coast of southern Japan on Sunday, churning up high waves that washed three American airmen out to sea and killed at least one.

In Suzuka, in central Japan, a French formula one driver was severely injured in an accident in the Japanese grand prix, which had to be shortened because the heavy rain made conditions too dangerous.

One of the three US airmen was found dead. The other two were missing, according to the air force and the Japanese coast guard. They had been on Okinawa island’s northern coast when they were overcome by the waves, according to Tsuguyoshi Miyagi of the coast guard’s Okinawa branch.

The air force said the search for the missing airmen had been interrupted by rough seas. Their names were being withheld pending notification of relatives. Okinawa is home to about half of the 50,000 American troops stationed in Japan.

In Suzuka, the Formula One driver Jules Bianchi of the Marussia team went off the track at a turn and hit a recovery vehicle that was removing a car that had crashed earlier. An unconscious Bianchi was taken to a nearby hospital, where he underwent emergency surgery for a severe head injury. Race officials said he was in critical condition.




Track of Typhoon Phanfone - Pacific Ocean tropical revolving storms


By late Sunday, Typhoon Phanfone was off the coast of Shikoku in south-western Japan, with winds of up to 90mph after hitting the regions of Okinawa and Kyushu, Japan’s Meteorological Agency said.

Several people on Kyushu island were injured in the typhoon. The storm also grounded more than 100 flights on Sunday and knocked out power to more than 9,500 Kyushu homes.

The storm triggered concern about possible landslides on the ash-covered volcano in central Japan that erupted on 27 September and killed at least 51 hikers. The search for a dozen people missing in the eruption was suspended on Sunday because of rain from the approaching storm.

The meteorological agency predicted up to 40cm (16in) of rain for central Japan by Monday morning.

Elsewhere in the Pacific, a separate typhoon whipped the Mariana Islands, including Guam, with high winds and heavy rain.

The eye of the typhoon in the Marianas was expected to pass over the small island of Rota, which has about 2,500 residents and many buildings made of concrete.

Typhoon Vongfong had maximum sustained winds estimated at 105mph, said Roger Edson of the National Weather Service in Guam. Winds on the islands of Guam, Tinian and Saipan were gusting to at least 55mph, he said.

Residents on Guam heeded warnings about high winds and possible flooding by taking shelter at designated public schools. The island government and many businesses were expected to be closed on Monday, and most flights were cancelled.








The Sea of Japan is a marginal sea of the western Pacific Ocean, between the Asian mainland, the Japanese archipelago and Sakhalin. It is bordered by Japan, North Korea, Russia and South Korea. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific Ocean. This isolation also reflects in the fauna species and in the water salinity, which is lower than in the ocean. The sea has no large islands, bays or capes. Its water balance is mostly determined by the inflow and outflow through the straits connecting it to the neighboring seas and Pacific Ocean. Few rivers discharge into the sea and their total contribution to the water exchange is within 1%.

The seawater is characterized by the elevated concentration of dissolved oxygen that results in high biological productivity. Therefore, fishing is the dominant economic activity in the region. The intensity of shipments across the sea has been moderate owing to political issues, but it is steadily increasing as a result of the growth of East Asian economies. A controversy exists about the sea name, with South Korea promoting the appellation East Sea (Korean:
동해 Donghae)


The Sea of Japan was once a landlocked sea when the land bridge of East Asia existed. The onset of formation of the Japan Arc was in Early Miocene. The Early Miocene period also corresponds to incipient opening of the Japan Sea, and the northern and southern parts of the Japanese archipelago that were separated from each other. During the Miocene, there was expansion of Sea of Japan. The northern part of the Japanese archipelago was further fragmented at later periods until the orogenesis of the northeastern Japanese archipelago began in the later Late Miocene. The southern part of the Japanese archipelago remained as a relatively large landmass. The land area had expanded northward in the Late Miocene. The orogenesis of high mountain ranges in the northeastern Japan started in Late Miocene and it lasts in Pliocene also.

For centuries, the sea had protected Japan from land invasions, particularly by the Mongols. It had long been navigated by Asian and, from the 18th century, by European ships. Russian expeditions of 1733–1743 mapped Sakhalin and the Japanese islands. In the 1780s, the Frenchman Jean-François de Galaup, comte de Lapérouse, traveled northward across the sea through the strait that was named after him. In 1796, another Frenchman Robert Broughton explored the Strait of Tartary, the eastern coast of the Russian Far East and the Korean Peninsula. In 1803–1806, the Russian navigator Adam Johann von Krusenstern while sailing across the globe in the ship Nadezhda also explored, in passing, the Sea of Japan and the eastern shores of Japanese islands. In 1849, another Russian explorer Gennady Nevelskoy discovered the strait between the continent and Sakhalin and mapped the northern part of the Strait of Tartary. Russian expeditions were made in 1853–1854 and 1886–1889 to measure the surface temperatures and record the tides. They also documented the cyclonal character of the sea currents. Other notable expeditions of the 19th century include the American North Pacific Exploring and Surveying Expedition (1853–1856) and British Challenger expedition (1872–1876). The aquatic life was described by V. K. Brazhnikov in 1899–1902 and P. Yu. Schmidt in 1903–1904. The Japanese scientific studies of the sea began only in 1915 and became systematic since the 1920s.




Relief of the Sea of Japan and nearby areas




The sea currents circulate in the counterclockwise direction. The Kuroshio (Japan Current), the Tsushima Current and the East Korea Warm Current bring warmer and more saline water to the north. There they merge into the Tsugaru Current and flow into the Pacific Ocean through the Tsugaru Strait. They also feed the Sōya Current and exit through the La Perouse Strait to the Sea of Okhotsk. The returning branch is composed of the Liman, North Korea and Central (or Mid-) Japan Sea currents which bring fresh and cold water along the Asian coast to the south.

Water temperature is mostly affected by exchange with the atmosphere in the northern part of the sea and by the currents in the southern part. Winter temperatures are 0 °C or below in the north and 10–14 °C in the south. In this season, there is a significant temperature difference between the western and eastern parts owing to the circular currents. So at the latitude of Peter the Great Gulf, the water temperature is about 0 °C in the west and 5–6 °C in the east. This east-west difference drops to 1–2 °C in summer, and the temperatures rise to 18–20 °C in the north and 25–27 °C in the south.

As a result of the enclosed nature of the sea, its waters form clearly separated layers which may show seasonal and spatial dependence. In winter, the temperature is almost constant with the depth in the northern part of the sea. However, in central-southern parts, it may be 8–10 °C down to 100–150 m, 2–4 °C at 200–250 m, 1.0–1.5 °C at 400–500 m and then remain at about 0 °C until the bottom. Heating by the sun and tropical monsoons increases the depth gradient in spring–summer. So in the north the surface layer (down to 15 m) may heat up to 18–20 °C. The temperature would sharply drop to 4 °C at 50 m, then slowly decrease to 1 °C at 250 m and remain so down to the seabed. On the contrary, the temperature in the south could gradually decrease to 6 °C at 200 m, then to 2 °C at 260 m and to 0.04–0.14 °C at 1000–1500 m, but then it would rise to about 0.3 °C near the bottom. This cold layer at about 1000 m is formed by sinking of cold water in the northern part of the sea in winter and is brought south by the sea currents; it is rather stable and is observed all through the year.

The hydrological isolation of the Sea of Japan also results in slightly lower average water salinity (34.09‰, where ‰ means parts per thousand) compared with the Pacific Ocean. In winter, the highest salinity at 34.5‰ is observed in the south where evaporation dominates over precipitation. It is the lowest at 33.8‰ in the south-east and south-west because of frequent rains and remains at about 34.09‰ in most other parts. Thawing of ice in spring reduces water salinity in the north, but it remains high at 34.60–34.70‰ in the south, partly because of the inflow of salty water through the Korea Strait. A typical variation of salinity across the sea in summer is 31.5‰ to 34.5‰ from north to south. The depth distribution of salinity is relatively constant. The surface layer tends to be more fresh in the sea parts which experience ice melting and rains. The average water density is 1.0270 g/cm3 in the north and 1.0255 g/cm3 in the south in winter. It lowers in summer to 1.0253 and 1.0215 g/cm3, respectively.

Few rivers flow into the Sea of Japan from mainland Asia, the largest being Tumen, Rudnaya, Samarga, Partizanskaya and Tumnin; all of them have mountainous character. In contrast, numerous large rivers flow from Honshū and Hokkaidō into the sea, including Japan’s four largest rivers in the Shinano, Ishikari, Agano and Mogami. The total annual river discharge into the sea is 210 km3 and is relatively constant through the year, except for a minor increase in July. Most water (97% or 52,200 km3) flows into the sea through the Korea Strait and discharges through the Tsugaru (64% or 34,610 km3), La Pérouse (10,380 km3) and Korea straits. Rainfall, evaporation and riverine inflow make only 1% of the water balance. Between October and April, the outflow exceeds the inflow due to the lower income through the Korea Strait; this balance reverses between May and September.

The sea has complex tides, which are induced by the tidal wave of the Pacific Ocean penetrating through the Korea Strait and Tsugaru strait. The tides are semi-diurnal (rise twice a day) in the Korea Strait and in the northern part of the Strait of Tartary. They are diurnal at the eastern shore of Korea, Russian Far East and the Japanese islands of Honshū and Hokkaidō. Mixed tides occur in Peter the Great Gulf and Korea strait. The tidal waves have a speed of 10–25 cm/s in the open sea. They accelerate in the Korea Strait (40–60 cm/s), La Pérouse Strait (50–100 cm/s) and especially in the Tsugaru Strait (100–200 cm/s). The amplitude of the tides is relatively low and strongly varies across the sea. It reaches 3 meters in the south near the Korea Strait, but quickly drops northwards to 1.5 meters at the southern tip of Korean Peninsula and to 0.5 meters at the North Korean shores. Similar low tides are observed in Hokkaidō, Honshū and south Sakhalin. The amplitude however increases to 2.3–2.8 meters toward the north of the Strait of Tartary due to its funnel-like shape. Apart from tides, the water level also experiences seasonal, monsoon-related variations across the entire sea with the highest levels observed in summer and lowest in winter. Wind may also locally change the water level by 20–25 cm; for example, it is higher in summer at the Korean and lower at the Japanese coasts.

The sea waters have blue to green-blue color and a transparency of about 10 meters. They are rich in dissolved oxygen, especially in the western and northern parts, which are colder and have more phytoplankton than the eastern and southern areas. The oxygen concentration is 95% of the saturation point near the surface, it decreases with the depth to about 70% at 3,000 meters.




Fishery had long been the main economic activity on the Sea of Japan. It is mainly carried out on and near the continental shelves and focuses on herring, sardines and bluefin tuna. These species are however depleted from after World War II. Squid is mostly caught near the sea center and salmon near the northern and southwestern shores. There is also a well-developed seaweed production. The importance of the fishery in the sea is illustrated by the territorial disputes between Japan and South Korea over Liancourt Rocks and between Japan and Russia over the Kuril Islands. It is also reflected in various legends, such as the legend of the Heishi rock, which says that once when herring vanished, an old fairy threw a bottle with a magic water into the sea, and the herring returned. The bottle got stuck to the seabed and turned into a rock, which became a representation of the God of the Sea of Japan.

Vladivostok is a base for the Russian whaling fleet. Although it operates in the northern seas, its production is processed and partly distributed in the Vladivostok area. Vladivostok is also a terminal point of the Trans-Siberian Railway which brings much goods to and from this major port. There is a regular ferry service across the Strait of Tartary between the Russian continental port of Vanino and Kholmsk in Sakhalin.

The sea has magnetite sands as well as natural gas and petroleum fields near the northern part of Japan and Sakhalin Island. The intensity of shipments across the sea is moderate, owing to the cold relations between many bordering countries. As a result, the largest Japanese ports are located on the Pacific coast, and the significant ports on the Sea of Japan are Niigata, Tsuruta and Maizuru. Major South Korean ports are Busan, Ulsan, and Pohang situated on the southeastern coast of the Korean Peninsula, but they also mainly target countries not bordering the Sea of Japan. The major Russian port of Vladivostok mainly serves inland cargos, whereas Nakhodka and Vostochny are more international and have a busy exchange with Japan and South Korea. Other prominent Russian ports are Sovetskaya Gavan, Alexandrovsk-Sakhalinsky and Kholmsk, and the major ports of North Korea are Wonsan, Hamhung and Chongjin. The intensity of shipments across the Sea of Japan is steadily increasing as a result of the growth of East Asian economies.




The use of the term "Sea of Japan" as the dominant name is a live point of contention. South Korea wants the name "East Sea" to be used, either instead of or in addition to "Sea of Japan;" while North Korea prefers the name "East Sea of Korea".


The primary issue in the dispute revolves around a disagreement about when the name "Sea of Japan" became the international standard. Japan claims the term has been the international standard since at least the early 19th century, while the Koreas claim that the term "Sea of Japan" arose later while Korea was under Japanese rule, and prior to that occupation other names such as "Sea of Korea" or "East Sea" were used in English. The International Hydrographic Organization, the international governing body for the naming bodies of water around the world, in 2012 recognized the term "Sea of Japan" as the only title for the sea, but will likely review the issue again in 2017, no doubt as evidence surfaces.


The Japanese Office for Foreign Affairs has produced a Youtube video featured on this page seeking to clarify the historical name usage position. There is no reason why North and South Korea cannot use the names that they prefer locally, on the proviso  that such use may not cause any international navigation confusion, which we are sure they would not advocate in any case.






Washington Post large-dangerous-typhoon-phanfone-heading-towards-japan-tokyo

Huffington Post 2014 typhoon-phanfone-okinawa

Global News typhoon-phanfone-heading-towards-japan-f1-grand-prix-to-continue

BBC world news asia typhoon phanfone

The Guardian typhoon-phanfone-japan-three-us-airmen-swept-out-sea

Wikipedia Sea_of_Japan

Nine MSN divers-nearly-swallowed-by-humpback-whales

Cascadia Research humpbacks

Sea Shepherd humpback_whale

Enchanted learning humpback whale

Maritime Australia Limited

tattoos sectasaur_antarctic_melt_john_storm_adventure_book_by_jameson_hunter





A humpback whale stikes a blow for anti whaling - The $Billion Dollar Whale movie












HMS Astute as a target for drone submarine hunters


DRONE SUBMARINE HKs - A low cost method of keeping tabs on the submarines of near neighbors who insist of patrols of their own. Any submarine operating in sovereign water other than that regarded as international waters, might be tracked and their crew know that they are the ones in danger from a drone vessel with no crew to sacrifice, should the worst come to the worst. In times of hostilities drone HKs might sink an enemy submarine as soon as it is located with torpedoes or depth charges. It is thus imperative that the position of friendly submarines is known at all times. It is a bit like the days of mines when allied shipping was sometimes sunk by allied mines.




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