出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/11/26 10:35:25」(JST)
| 「日本海」のその他の用法については「日本海 (曖昧さ回避)」をご覧ください。 |
日本海（にほんかい）は、西太平洋の縁海で、樺太（サハリン）、北海道、本州、九州、ユーラシア大陸の大韓民国（韓国）、朝鮮民主主義人民共和国（北朝鮮）、ロシア連邦に囲まれている。
ユーラシア大陸と樺太の間の間宮海峡（タタール海峡）、樺太と北海道の間の宗谷海峡でオホーツク海と繋がっており、北海道と本州の間の津軽海峡では太平洋と、九州と対馬の間の対馬海峡東水道、対馬と韓国の間の朝鮮海峡で東シナ海と繋がっている。
国際水路機関の定義による海上の境界は、北東ではロシア本土のSushcheva岬と樺太西岸のTuik岬とを結ぶ線、樺太南端の西能登呂岬（またはクズネツォワ岬）と北海道北端の宗谷岬（または野寒布岬）とを結ぶ線、道南の恵山岬と青森県の尻屋崎とを結ぶ線、南東では山口県下関市の村崎ノ鼻、六連島、北九州市の八幡岬とを結ぶ線、および南西では長崎県の野母崎、福江島の大瀬埼、韓国済州島最南端のプナム崎、全羅南道の玉島、珍島を結ぶ線で囲まれる海域となっており[1][2]、南西部では対馬海峡・朝鮮海峡よりも西の五島列島や韓国南部まで含まれている。しかし、一般的には九州北西部、特に長崎県西方や五島列島周辺の海域を「日本海」と呼ぶことはほぼ皆無で、環境省[3]や気象庁[4][5]、長崎県[6]などの資料では、これらの海域は日本海には含まれなかったり、東シナ海の一部とされている。
古称は鯨海（けいかい）[要出典]。「日本海」と最初に命名したのは、ロシア海軍のクルーゼンシュテルン提督（1770－1846）である[1][7]。英語ではSea of JapanまたはJapan Sea。ラテン語ではMare Iaponicum（マレ・ヤポーニクム）。フランス語ではmer du Japon、ドイツ語ではJapanisches Meer、ロシア語ではЯпонское море[8]。朝鮮語では、韓国では동해（トンヘ、東海）、한국해（ハングケ、韓国海）、北朝鮮では조선동해（チョソントンヘ、朝鮮東海）、조선해（チョソンヘ、朝鮮海）との呼称が一般的である。その他동조선해（トンチョソンヘ、東朝鮮海）などとも呼ばれている。なお、一時期までは일본해（イルボンヘ、日本海）と呼ばれていた。
現在、国連及び国際的な海図の大半は「日本海」（もしくはその訳語）という表記を使用しており、国際的にこれが一般的である。海図上の名称の基準になっている国際水路機関（IHO）の「大洋と海の境界」(1953年)においても、Japan Sea の名称を用いている[9][10]。
韓国はこれは日本による植民地統治の残滓であるとして「東海」「韓国海」「朝鮮海」等への置き換えもしくは併記を主張しているが、「日本海」は17世紀初頭の清の世界地図坤輿万国全図や明治以前発行の欧米の地図に既に記載されている。
平均水深は1,752m、最も深い地点で3,742mで、表面積は978,000 km²である。中央の大和堆（水深約400m）を挟んで主に3つの深い海盆があり北に日本海盆（水深およそ3,000m）、南東にやや浅い大和海盆、南西に対馬海盆（ともに水深およそ2500m）と呼ばれている。また、富山湾沖から水深1,000mにも達する富山深海長谷が約750kmにわたって延びている（富山平野や砺波平野はその延長である）。大陸棚が東部沿岸に広がっているが、西部、特に朝鮮半島沿いは非常に狭く、幅は30km程度である。
海峡の水深が浅いため外海との海水の交換は少なく、唯一対馬海峡から対馬海流が流入するのみである。暖流の流入は日本の温暖な気候に影響を与えている。北部には寒流のリマン海流が流れているが、地質調査からかつて親潮が流れていた事が明かとなった。
深層には太平洋とは全く性質を異にする日本海固有水と呼ばれる、寒冷で溶存酸素に富んだ海水が分布する。
北方と南西海域は豊富な水産資源が得られ、鉱物資源や天然ガス、わずかながら石油そしてメタンハイドレートの存在など経済的にも重要な海域とされる。
日本列島は4000万年前まで大陸の一部であったが、4000万年前頃から2000万年前にかけて大陸から分離し日本海の原型が形成され、その後拡大が進み数百万年前にはほぼ現在の配置になった。対馬海峡はまだユーラシア大陸と陸続きで、対馬海峡が形成されたのは第四紀になってからと言われている。その後氷期間氷期の世界的な海水準の変化によって、水深130m程度の浅い海峡は閉じたり開いたりを繰り返していた。その為、堆積物の岩相や同位体の構成比、元素濃度は劇的に変化をしている[11]。
樺太から日本列島沿岸に沿って海嶺やマグニチュード7クラスの地震の多発域が帯状に連なっており、これを日本海東縁変動帯と呼ぶ。日本海東縁変動帯では、ネフチェゴルスク地震、北海道南西沖地震、日本海中部地震、庄内沖地震、新潟地震、新潟県中越地震、新潟県中越沖地震などが発生している[12][13]。
太平洋より種族数が少なく固有種も乏しいことから、日本海の形成時代はあまり古くないといわれている。カニなどの沿岸性底動物は一般に豊富で、能登半島を境にしてその動物相にやや変化がみられる。太平洋岸に比べ、対馬暖流の影響で南方系種族の北限がはるか北方にのびている。例を挙げると、サザエは日本海側では青森でも漁獲されるのに対し太平洋側では関東以北には現れない。 プランクトンは沿海沖の冷水域および陸棚上に多く、中央部に乏しい。種類は対馬暖流系の暖水種と、リマン寒流系の冷水種に分けられるが、両者の分布は水塊分布ほど明確に区分されず、混在海域が広い。北方系の魚類としては、ニシン、サケ、マス、タラなどがあり、南方系の魚類としてはやや温帯性に属するブリが多いが、代表的な暖水魚であるカツオ、マグロなども地球温暖化による海水温の上昇により西側が産卵地域となり漁獲量が増加しているが乱獲が問題となっている。魚類としてもっと重要なものは温帯性のマダイ、マイワシ、サバ、カレイなどである。これらの分布を太平洋と比較すると、次のような特徴がある。
また古来からクジラの回遊経路として知られ、かつて沿岸には多数の捕鯨漁村が存在した。これらのほとんどは捕鯨により激減したため今では稀にしか見られないが、現在でも多数のイルカ類や、少数だがヒゲクジラでは珍しく大規模な回遊を行わないミンククジラやナガスクジラの個体群も存在する。
漂着物として、主に韓国、中国など日本海を航行する貨物船や漁船、また朝鮮半島や日本本土から不法投棄されるゴミが海流にのって、対馬や日本海沿岸に漂着する。その量は膨大で沿岸地方自治体の財政を圧迫するほどである。
さらに、ロシアなどが遺棄していた放射性物質は深海を汚染しているおそれが大きく、カニや深海魚の汚染に不安感がもたれている。特に経済が悪化していた当時のロシアでは太平洋艦隊の古い原子力潜水艦の原子炉を日本海公海上の海溝に投棄していたことが問題とされている[14]。 韓国政府は68年から4年間、約45トンの放射性廃棄物を日本海の鬱陵島(ウルルンド)から南に12海里離れた水深約2200メートル地点に投棄した。 [15]
また、冬季の天候の悪化時に起きる海難事故では、ナホトカ号重油流出事故のように大量の重油で沿岸部を汚染する事件が多発している。中国、ロシア、韓国船の中には船内を海水で洗浄した廃油を海に投棄する船が後をたたない。主に冬から春にかけて、航行中の船から材木などが大量に流出し航行に危険をもたらす事件もおこっている。
沿岸部の岩礁地帯の植物が死滅して、焼いたサザエの殻のように、水面下の岩についた貝等の屍骸で磯全体が広範囲にわたって白く焼けたように見えることから、この呼び名がある。 日本海沿岸部全体で観察される現象で、沿岸部での魚の激減、えさの減少から沿岸部で産卵されて育つ人間に有用な魚の稚魚の成長が難しくなることなど、漁業全体への深刻な影響が懸念される。 川の水が流入する直近の場所では少ないことから、海水の変化が原因と考えられている。 海水の変化の理由として、有力な説は船底塗料等の中に含まれる環境ホルモンによる海洋汚染、流入する河川の治水による有機物の減少、最新の説には、温暖化による海水の有機物の減少（貧栄養化現象、栄養減化現象）をあげる説等があるが、原因は不明である。 なお、現代の磯を見慣れている人には「磯焼け」が常態であるのでこの言葉に実感はないが、半世紀前の人々が普通に見た磯（水中）は、岩などが見えないほど海草が生い茂っていたのである。
能登金剛や東尋坊などの荒々しい海の光景や、天橋立、鳥取砂丘、千里浜海岸、丹後の鳴き砂など海と砂の作る不思議な海岸の光景が有名である。ほかにも多くの風光明媚な観光地や天然記念物が散在し、北海道から対馬まで、観光資源としての価値も高い。
日本海に面した地域を指定した国立公園には利尻礼文サロベツ国立公園、山陰海岸国立公園、大山隠岐国立公園の3公園がある。
暑寒別天売焼尻国定公園、ニセコ積丹小樽海岸国定公園、津軽国定公園、男鹿国定公園、鳥海国定公園、佐渡弥彦米山国定公園、能登半島国定公園、越前加賀海岸国定公園、若狭湾国定公園、丹後天橋立大江山国定公園、北長門海岸国定公園、玄海国定公園、壱岐対馬国定公園など多くの地が国定公園の指定を受けているが、近時、道路港湾によりその風景は破壊されつつある。
多数のフェリー航路が設定されている。
また、上海から北米への航路は、日本海に入った後津軽海峡を通り抜けるように太平洋へと向かう。この航路を採用する期間は夏季のみ。その理由は台風を避ける為、黒潮など激しい潮の流れを避ける為の２つである。
南西部にある竹島について日韓で領土問題が起きている。
| [ヘルプ] |
| ウィキメディア・コモンズには、日本海に関連するメディアがあります。 |
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| この項目は、日本の地理に関連した書きかけの項目です。この項目を加筆・訂正などしてくださる協力者を求めています（Portal:日本の地理）。 |
| この項目は、ロシアの地理に関連した書きかけの項目です。この項目を加筆・訂正などしてくださる協力者を求めています（P:ヨーロッパ/PJ:東ヨーロッパ）。 |
| Sea of Japan | |||||||
| Japanese name | |||||||
|---|---|---|---|---|---|---|---|
| Kanji | 日本海 | ||||||
| Hiragana | にほんかい | ||||||
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| North Korean name | |||||||
| Chosŏn'gŭl | 조선동해 | ||||||
| Hancha | 朝鮮東海 | ||||||
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| South Korean name | |||||||
| Hangul | 동해 | ||||||
| Hanja | 東海 | ||||||
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| Russian name | |||||||
| Russian | Японское море | ||||||
| Romanization | Yaponskoye more | ||||||
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.[1] 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).[2]
The International Hydrographic Organization defines the limits of the "Japan Sea" as follows:[3]
The Sea of Japan was once a landlocked sea when the land bridge of East Asia existed.[4] The onset of formation of the Japan Arc was in Early Miocene.[5] 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.[5] During the Miocene, there was expansion of Sea of Japan.[5] 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.[5] The southern part of the Japanese archipelago remained as a relatively large landmass.[5] The land area had expanded northward in the Late Miocene.[5] The orogenesis of high mountain ranges in the northeastern Japan started in Late Miocene and it lasts in Pliocene also.[5]
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Map showing Japanese archipelago, Sea of Japan and surrounding part of continental East Asia in Early Miocene (23–18 Ma).
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Map showing Japanese archipelago, Sea of Japan and surrounding part of continental East Asia in Middle Pliocene to Late Pliocene (3.5–2 Ma).
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Nowadays it is bound by the Russian mainland and Sakhalin island to the north, the Korean Peninsula to the west, and the Japanese islands of Hokkaidō, Honshū and Kyūshū to the east and south. It is connected to other seas by five straits: the Strait of Tartary between the Asian mainland and Sakhalin; La Pérouse Strait between the islands of Sakhalin and Hokkaidō; the Tsugaru Strait between the islands of Hokkaidō and Honshū; the Kanmon Straits between the islands of Honshū and Kyūshū; and the Korea Strait between the Korean Peninsula and the island of Kyūshū. The Korea Strait is composed of the Western Channel and the Tsushima Strait, on either side of Tsushima Island. The straits were formed in recent geologic periods. The oldest of them are the Tsugaru and Tsushima straits. Their formation had interrupted the migration of elephants into the Japanese islands at the end of the Neogene Period (about 2.6 million years ago). The most recent is La Perouse Strait. Its formation about 60,000 to 11,000 years ago had closed the path used by the mammoths which had earlier moved to the northern Hokkaidō.[6] All the straits are rather shallow with a minimal depth of the order of 100 meters or less. This hinders water exchange thereby isolating the water and aquatic life of the Sea of Japan from the neighboring seas and oceans.[7] The sea has a surface area of about 978,000 km2 (378,000 sq mi), a mean depth of 1,752 m (5,748 ft) and a maximum depth of 3,742 m (12,277 ft). It has a carrot-like shape, with the major axis extending from southwest to northeast and a wide southern part narrowing toward the north. The coastal length is about 7,600 km with the largest part (3,240 km) belonging to Russia. The sea extends from north to south for more than 2,255 km and has a maximum width of about 1,070 km.[8] It has three major basins: the Yamato Basin in the southeast, the Japan Basin in the north and the Tsushima Basin (Ulleung Basin) in the southwest.[6] The Japan Basin is of oceanic origin and is the deepest part of the sea, whereas the Tsushima Basin is the shallowest with the depths below 2,300 meters.[8] On the eastern shores, the continental shelves of the sea are wide, but on the western shores, particularly along the Korean coast, they are narrow, averaging about 30 kilometers.[7]
There are three distinct continental shelves in the northern part (above 44°N). They form a staircase-like structure with the steps slightly inclined southwards and submerged to the depths of 900–1400, 1700–2000 and 2300–2600 meters. The last step sharply drops to the depths of about 3,500 meters toward the central (deepest) part of the sea. The bottom of this part is relatively flat, but has a few plateaus. In addition, an underwater ridge rising up to 2,300 meters runs from north to south through the middle of the central part.[7]
The Japanese coastal area of the sea consists of Okujiri Ridge, Sado Ridge, Hakusan Banks, Wakasa Ridge and Oki Ridge. Yamato Ridge is of continental origin and is composed of granite, rhyolite, andesite and basalt. It has uneven bottom covered with boulders of volcanic rock. Most other areas of the sea are of oceanic origin. Seabed down to 300 meters (980 feet) is of continental nature and is covered with a mixture of mud, sand, gravel and fragments of rock. The depths between 300 and 800 meters (980 and 2,620 ft) are covered in hemipelagic sediments (i.e., of semi-oceanic origin); these sediments are composed of blue mud rich in organic matter. Pelagic sediments of red mud dominate the deeper regions.[6]
There are no large islands in the sea. Most of the smaller ones are located near the eastern coast, except for Ulleungdo (South Korea). The most significant islands are Moneron, Rebun, Rishiri, Okushiri, Ōshima, Sado, Okinoshima, Ulleungdo, Askold, Russky and Putyatin. The shorelines are relatively straight and are lacking large bays or capes; the coastal shapes are simplest for Sakhalin and are more winding in the Japanese islands. The largest bays are Peter the Great Gulf, Sovetskaya Gavan, Vladimira, Olga, Posyet in Russia, East Korea Bay in North Korea and Ishikari (Hokkaidō), Toyama and Wakasa (Honshū) in Japan. Prominent capes include Lazareva, Peschanyi (sandy), Povorotny, Gromova, Pogibi, Tyk, Korsakova, Crillon, Sōya, Nosappu, Tappi, Nyuda, Rebun, Rishiri, Okushiri, Daso and Oki.[7][8]
The sea climate is characterized by warm waters and monsoons. This combination results in strong evaporation, which is especially noticeable between October and March when the strong (12–15 m/s or higher) northwestern monsoon wind brings cold and dry continental air. The evaporation is blown further south causing snowfall in the mountainous western coasts of Japan. This winter monsoon brings typhoons and storms with the waves reaching 8–10 meters which erode the western coasts of Japan. Tsunami waves were also recorded in the sea. In addition, the monsoon enhances the surface water convection, down to the depths of 30 meters. The coldest months are January and February with the average air temperature of −20 °C in the north and 5 °C in the south. The northern one-quarter of the sea, particularly the Siberian coast and the Strait of Tartary, freezes for about 4–5 months.[6] The timing and extent of freezing vary from year to year, so ice may start forming in the bays as early as in October and its remains may be seen even in June. Ice cover is continuous only in the bays and forms floating patches in the open sea. Ice melting in spring results in cold currents in the northern areas.[7]
In summer the wind weakens to 2–7 m/s and reverses its direction, blowing warm and humid air from the North Pacific onto the Asian mainland. The warmest month is August with the average air temperature of 15 °C in the north and 25 °C in the south.[7] Annual precipitation increases from 310–500 mm in the north-west to 1,500–2,000 mm in the south-east.[8]
A peculiar turbulent cloud pattern, named Von Karman vortices, is sometimes observed over the Sea of Japan. It requires a stable field of low clouds driven by the wind over a small (isolated) and tall obstacle, and usually forms over small mountainous islands.[9] The Sea of Japan meets these conditions as it has frequent winds and cloudy skies, as well as compact, tall islands such as Rishiri (1,721 m), Ulleungdo (984 m) and Ōshima (732 m).
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.[6]
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.[7]
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.[6][7]
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.[7] 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.[8]
Few rivers flow into the Sea of Japan from mainland Asia, the largest being Tumen,[8] 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.[7] 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.[7][8]
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.[7]
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.[7][8]
The high concentration of dissolved oxygen results in the rich aquatic life of the Sea of Japan – there are more than 800 species of aquatic plants and more than 3,500 animal species, including more than 900 species of crustaceans, about 1000 of fish and 26 of mammals. The coastal areas contain several kg/m2 of biomass. Pelagic (oceanic) fishes include saury, mackerel, Jack mackerels, sardines, anchovies, herring, sea bream, squid and various species of salmon and trout. The demersal (sea-bottom) fishes include cod, pollock and Atka mackerel. Mammals are represented by seals and whales, and the crustaceans by shrimps and crabs.[6] Because of the shallow straits connecting the sea with Pacific Ocean, the sea of Japan has no characteristic oceanic deep-water fauna.[8] Flora and fauna unique to the region near the Sea of Japan are known as "Japan Sea elements".[5]
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.[6] There is also a well-developed seaweed production.[7] 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.[10][11]
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.[7]
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.[8] The intensity of shipments across the Sea of Japan is steadily increasing as a result of the growth of East Asian economies.[6]
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.[6][8]
The use of the term "Sea of Japan" as the dominant name is a point of contention. South Korea wants the name "East Sea" to be used, either instead of or in addition to "Sea of Japan;"[12][13] while North Korea prefers the name "East Sea of Korea".[14]
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,[15] 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.[16] 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.[17]
This article incorporates CC-BY-2.0 text from this reference:[5]
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Coordinates: 40°N 135°E / 40°N 135°E / 40; 135
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