Yellow Sea | |
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Location | East Asia |
Coordinates | 38°0′N123°0′E / 38.000°N 123.000°E |
River sources | Yellow River, Hai River, Yalu River, Taedong River, Han River |
Basin countries | China, North Korea, and South Korea |
Surface area | 380,000 km2 (150,000 sq mi) |
Average depth | Avg. 44 m (144 ft) |
Max. depth | Max. 152 m (499 ft) |
Yellow Sea | |||||||||||||||
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Chinese name | |||||||||||||||
Simplified Chinese | 黄 海 | ||||||||||||||
Traditional Chinese | 黃 海 | ||||||||||||||
Literal meaning | Yellow Sea | ||||||||||||||
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Korean name | |||||||||||||||
Hangul | 황해or 서해 | ||||||||||||||
Hanja | 黃 海 or 西 海 | ||||||||||||||
Literal meaning | Yellow Sea or West Sea | ||||||||||||||
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The Yellow Sea,also known as the North Sea,is a marginal sea of the Western Pacific Ocean located between mainland China and the Korean Peninsula,and can be considered the northwestern part of the East China Sea.
It is one of four seas named after color terms (the others being the Black Sea,the Red Sea and the White Sea),and its name is descriptive of the golden-yellow color of the silt-ridden water discharged from major rivers.
The innermost bay of northwestern Yellow Sea is called the Bohai Sea (previously Gulf of Zhili / Beizhili),into which flow some of the most important rivers of northern China,such as the Yellow River (through Shandong province and its capital Jinan),the Hai River (through Beijing and Tianjin) and the Liao River (through Liaoning province). The northeastern extension of the Yellow Sea is called the Korea Bay,into which flow the Yalu River,the Chongchon River and the Taedong River.
The International Hydrographic Organization defines the limits of the Yellow Sea ("Hwang Hai") as follows: [1]
The Yellow Sea is separated from the Sea of Japan by the boundary from the southern end of Haenam Peninsula in Jeollanamdo to Jeju Island and divided into the East China Sea by the boundary from the west end of Jeju Island to the Yangtze River estuary.
The Yellow Sea, excluding the Bohai, extends by about 960 km (600 mi) from north to south and about 700 km (430 mi) from east to west; it has an area of approximately 380,000 km2 (150,000 sq mi) and a volume of about 17,000 km3 (4,100 cu mi). [3] Its depth is only 44 m (144 ft) on average, with a maximum of 152 m (499 ft). The sea is a flooded section of continental shelf that formed after the last glacial period (some 10,000 years ago) as sea levels rose 120 m (390 ft) to their current levels. The depth gradually increases from north to south. [3] The sea bottom and shores are dominated by sand and silt brought by the rivers through the Bohai Sea (Liao River, Yellow River, Hai He) and the Korea Bay (Yalu River). These deposits, together with sand storms are responsible for the yellowish colour of the water referenced in the sea's name. [4] The sea annually receives so much sand and silt from rivers such as the Yellow River, that it actually turns into a golden-yellow colour. [5] [6]
The seas surrounding Korea, which occupy a corner of Northeast Asia, border the "island nation" from the east, south, and west. Korea has named these the East Sea, South Sea, and West Sea (officially known as the Yellow Sea), respectively. [7]
Major islands of the sea include Anmado, Baengnyeongdo, Daebudo, Deokjeokdo, Gageodo, Ganghwado, Hauido, Heuksando, Hongdo, Jejudo, Jindo, Muuido, Sido, Silmido, Sindo, Wando, Yeongjongdo and Yeonpyeongdo (all in South Korea).
The area has cold, dry winters with strong northernly monsoons blowing from late November to March. Average January temperatures are −10 °C (14 °F) in the north and 3 °C (37 °F) in the south. Summers are wet and warm with frequent typhoons between June and October. [3] Air temperatures range between 10 and 28 °C (50 and 82 °F). The average annual precipitation increases from about 500 mm (20 in) in the north to 1,000 mm (39 in) in the south. Fog is frequent along the coasts, especially in the upwelling cold-water areas. [4]
The sea has a warm cyclone current, forming part of the Kuroshio Current, which diverges near the western part of Japan and flows northward into the Yellow Sea at a speed of less than 0.8 km/h (0.50 mph). Southward currents prevail near the sea coast, especially in the winter monsoon period. [4]
The water temperature is close to freezing in the northern part in winter, so drift ice patches and continuous ice fields form and hinder navigation between November and March. The water temperature and salinity are homogeneous across the depth. The southern waters are warmer at 6–8 °C (43–46 °F). In spring and summer, the upper layer is warmed up by the sun and diluted by the fresh water from rivers, while the deeper water remains cold and saline. This deep water stagnates and slowly moves south. Commercial bottom-dwelling fishes are found around this mass of water, especially at its southern part. Summer temperatures range between 22 and 28 °C (72 and 82 °F). The average salinity is relatively low, at 30‰ in the north to 33–34‰ in the south, dropping to 26‰ or lower near the river deltas. In the southwest monsoon season (June to August) the increased rainfall and runoff further reduce the salinity of the upper sea layer. [4] Water transparency increases from about 10 meters (33 ft) in the north up to 45 meters (148 ft) in the south. [3]
Tides are semidiurnal, i.e. rise twice a day. Their amplitude varies between about 0.9 and 3 meters (3.0 and 9.8 ft) at the coast of China. Tides are higher at the Korean Peninsula, typically ranging between 4 and 8 meters (13 and 26 ft) and reaching the maximum in spring. The tidal system rotates in a counterclockwise direction. The speed of the tidal current is generally less than 1.6 km/h (0.99 mph) in the middle of the sea, but may increase to more than 5.6 km/h (3.5 mph) near the coasts. [4] The fastest tides reaching 20 km/h (12 mph) occur in the Myeongnyang Strait between Jindo Island and the Korean Peninsula. [9]
The tide-related sea level variations result in a land pass 2.9 km (1.8 mi) long and 10–40 meters (33–131 ft) wide opening for approximately an hour between Jindo and Modo islands. The event occurs about twice a year, at the beginning of May and in the middle of June. It had long been celebrated in a local festival called "Jindo Sea Parting Festival", but was largely unknown to the outside world until 1975, when the French ambassador Pierre Randi described the phenomenon in a French newspaper. [10] [11] [12]
The sea is rich in seaweed (predominantly kelp, Laminaria japonica), cephalopods, crustaceans, shellfish, clams, and especially in blue-green algae which bloom in summer and contribute to the water color (see image above). For example, the seaweed production in the area was as high as 1.5 million tonnes in 1979 for China alone. The abundance of all these plant and animal species increases toward the south and indicates a high sea productivity, accounting for the diversity of fish species and high fish yield from the sea. [14] Several species of goby new to science have been discovered recently[ when? ] in the Yellow Sea. [15]
The southern part of the Yellow Sea, including the entire west coast of Korea, contains a 10 km-wide (6.2 mi) belt of intertidal mudflats, which has the total area of 2,850 km2 (1,100 sq mi) and is maintained by 4–10 m (13–33 ft). Those flats consist of highly productive sediments with a rich benthic fauna and are of great importance for migratory waders and shorebirds. [16] Surveys show that the area is the single most important site for migratory birds on northward migration in the entire East Asian – Australasian Flyway, with more than 35 species occurring in internationally significant numbers. Two million birds, at minimum, pass through at the time, and about half that number use it on southward migration. [17] [18] About 300,000 migrating birds were transiting annually only through the Saemangeum tidal flat area. This estuary was however dammed by South Korea in 1991–2006 that resulted in drying off the land. [19] Land reclamation also took 65% of the intertidal area (of China, North Korea and South Korea) between the 1950s and 2002, [20] and as of 2005 there were plans to reclaim a further 45%. [21]
Populations of oceanic megafauna, such as marine mammals, sea turtles, and larger fish, have decreased in modern times, not only due to pollution but also due to hunting. Japanese industrial whaling [22] and illegal mass operations by the Soviet Union with support from Japan [23] have been major drivers of population decline. Species that reside in the area today include spotted seals, and cetaceans such as minke whales, killer whales, [24] false killer whales, and finless porpoises, but nonetheless all the remnants of species listed could be in very small numbers. Historically, large whales were very abundant either for summering and wintering in the Yellow and Bohai Seas. For example, a unique population of resident fin whales and gray whales [25] were historically presented, [26] or possibly hosted some North Pacific right whales [27] [28] and Humpback whales (3 whales including a cow calf pair was observed at Changhai County in 2015 [29] [30] ) year-round other than migrating individuals, and many other migratory species such as Baird's beaked whales. [31] Even blue whales, Japanese sea lions, dugongs (in southern regions only), [32] and leatherback turtles used to breed or migrate into Yellow and Bohai seas. [33]
Spotted seals are the only resident species of seal in the Yellow Sea. A sanctuary for these seals is situated at Baengnyeongdo, which is also known for its finless porpoises. [34] Great white sharks have also been known to prey on seals in the area. [35]
The coasts of the Yellow Sea are very densely populated, at approximately 250 inhabitants per square kilometer (650/sq mi). [36] The sea waters had been used for fishing by the Chinese, Korean and Japanese ships for centuries. Especially rich in fish are the bottom layers. About 200 fish species are exploited commercially, especially sea bream, croakers, lizard fishes, prawns, cutlassfish, horse mackerel, squid, eel, filefish, Pacific herring, chub mackerel, flounder [37] and jellyfish. [38] The intensity of fishing has been gradually increasing for China and Korea and decreasing for Japan. For example, the production volumes for China rose from 619,000 tonnes in 1985 to 1,984,400 tonnes in 1996. [39] All species are overfished, however, and while the total catchments are rising, the fish population is continuously declining for most species. [4] [40]
Navigation is another traditional activity in the Yellow Sea. The main Chinese ports are Dalian, Tianjin, Qingdao and Qinhuangdao. The major South Korean ports on the Yellow Sea are Incheon, Gunsan and Mokpo, and that for North Korea is Nampho, the outport of Pyongyang. The Bohai Train Ferry provides a shortcut between the Liaodong Peninsula and Shandong. [4] A major naval accident occurred on 24 November 1999 at Yantai, Shandong, China when the 9,000-ton Chinese ferry Dashun caught fire and capsized in rough seas. About 300 people were killed, making it the worst maritime incident in China. [41]
Oil exploration has been successful in the Chinese and North Korean portions of the sea, with the proven and estimated reserves of about 9 and 20 billion tonnes, respectively. [42] However, the study and exploration of the sea is somewhat hindered by insufficient sharing of information between the involved countries. China initiated collaborations with foreign oil companies in 1979, but this initiative declined later. [4]
A major oil spill occurred on 16 July 2010 when a pipeline exploded at the north-east port of Dalian, causing a wide-scale fire and spreading about 1,500 tonnes of oil over the sea area of 430 km2 (170 sq mi). The port had been closed and fishing suspended until the end of August. Eight hundred fishing boats and 40 specialized vessels were mobilized to relieve the environmental damage. [43]
The Yellow Sea is considered among the most degraded marine areas on earth. [44] Loss of natural coastal habitats due to land reclamation has resulted in the destruction of more than 60% of tidal wetlands around the Yellow Sea coastline in approximately 50 years. [20] Rapid coastal development for agriculture, aquaculture and industrial development are considered the primary drivers of coastal destruction in the region. [20] This degree of loss of area, widespread pollution, algal blooms and declines of invertebrate and vertebrate fauna have resulted in the classification of this ecosystem as endangered. [45]
In addition to land reclamation, the Yellow Sea ecosystem is facing several other serious environmental problems. Pollution is widespread [46] and deterioration of pelagic and benthic habitat quality has occurred, and harmful algal blooms frequently occur. [47] Invasion of introduced species are having a detrimental effect on the Yellow Sea environment. There are 25 intentionally introduced species and 9 unintentionally introduced species in the Yellow Sea Large Marine Ecosystem. [44] Declines of biodiversity, fisheries and ecosystem services in the Yellow Sea are widespread. [44]
The tidal flats of the Yellow Sea are considered endangered. [45]
On 1 November 2018, officials from South Korea's Ministry of National Defense confirmed that "peace zones" had been established by the North and South Korean militaries in the Yellow Sea area that touches the North and South Korean demarcation line. [48] A buffer zone was also created in the Yellow Sea's Northern Limit Line (NLL).[ citation needed ]
South Korea is located in East Asia, on the southern portion of the Korean Peninsula located out from the far east of the Asian landmass. The only country that shares a land border with South Korea is North Korea, lying to the north with 238 kilometres (148 mi) of the border running along the Korean Demilitarized Zone. South Korea is mostly surrounded by water and has 2,413 kilometres (1,499 mi) of coast line along three seas; to the west is the Yellow Sea, to the south is the East China Sea, and to the east is the Sea of Japan. Geographically, South Korea's landmass is approximately 100,364 square kilometres (38,751 sq mi). 290 square kilometres (110 sq mi) of South Korea are occupied by water. The approximate coordinates are 37° North, 128° East.
The Yellow River is the second-longest river in China and the sixth-longest river system on Earth, with an estimated length of 5,464 km (3,395 mi) and a watershed of 795,000 km2 (307,000 sq mi). Beginning in the Bayan Har Mountains, the river flows generally eastwards before entering the 1,500 km (930 mi) long Ordos Loop, which runs northeast at Gansu through the Ordos Plateau and turns east in Inner Mongolia. The river then turns sharply southwards to form the border between Shanxi and Shaanxi, turns eastwards at its confluence with the Wei River, and flows across the North China Plain before emptying into the Bohai Sea. The river is named for the yellow color of its water, which comes from the large amount of sediment discharged into the water as the river flows through the Loess Plateau.
The Sea of Japan
is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific Ocean. This isolation also affects faunal diversity and salinity, both of which are lower than in the open 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 the Pacific Ocean. Few rivers discharge into the sea and their total contribution to the water exchange is within 1%.The Bay of Fundy is a bay between the Canadian provinces of New Brunswick and Nova Scotia, with a small portion touching the U.S. state of Maine. It is an arm of the Gulf of Maine. Its tidal range is the highest in the world. The name is probably a corruption of the French word fendu, meaning 'split'.
Bohai Bay is one of the three major bays of the Bohai Sea, the northwestern and innermost gulf of the Yellow Sea. It is bounded by the coastlines of eastern Hebei province, Tianjin municipality and northern Shandong province south of the Daqing River estuary and north of the Yellow River estuary. It is the most southerly water in the northern hemisphere where sea ice can form.
Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal flat ecosystems are as extensive globally as mangroves, covering at least 127,921 km2 (49,391 sq mi) of the Earth's surface. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries; they are also seen in freshwater lakes and salty lakes alike, wherein many rivers and creeks end. Mudflats may be viewed geologically as exposed layers of bay mud, resulting from deposition of estuarine silts, clays and aquatic animal detritus. Most of the sediment within a mudflat is within the intertidal zone, and thus the flat is submerged and exposed approximately twice daily.
The Leizhou Peninsula, alternately romanized as the Luichow Peninsula, is a peninsula in the southernmost part of Guangdong province in South China. As of 2015, the population of the peninsula was 5,694,245. The largest city by population and area on the peninsula is Zhanjiang.
Pulicat Lake is the second largest brackish water lagoon in India,, measuring 759 square kilometres (293 sq mi). A major part of the lagoon lies in the Tirupati district of Andhra Pradesh. The lagoon is one of three important wetlands that attracts northeast monsoon rain clouds during the October to December season. The lagoon comprises the following regions: Pulicat Lake, Marshy/Wetland Land Region (AP), Venadu Reserve Forest (AP), and Pernadu Reserve Forest (AP). The lagoon was cut across in the middle by the Sriharikota Link Road, which divided the water body into lagoon and marshy land. The lagoon encompasses the Pulicat Lake Bird Sanctuary. The barrier island of Sriharikota separates the lagoon from the Bay of Bengal and is home to the Indian Space Research Organisation's Satish Dhawan Space Centre.
Foxe Basin is a shallow oceanic basin north of Hudson Bay, in Nunavut, Canada, located between Baffin Island and the Melville Peninsula. For most of the year, it is blocked by sea ice and drift ice made up of multiple ice floes.
The spoon-billed sandpiper is a small wader which breeds on the coasts of the Bering Sea and winters in Southeast Asia. This species is highly threatened, and it is said that since the 1970s the breeding population has decreased significantly. By 2000, the estimated breeding population of the species was 350–500.
Saemangeum is an estuarine tidal flat on the coast of the Yellow Sea in South Korea. It was dammed by the government of South Korea's Saemangeum Seawall Project, completed in 2006, after a long fight between the government and environmental activists, and is scheduled to be converted into either agricultural or industrial land. Prior to 2010, it had played an important role as a habitat for migratory birds.
The Saemangeum Seawall, on the south-west coast of the Korean peninsula, is the world's longest man-made dyke, measuring 33 kilometres (21 mi). It runs between two headlands, and separates the Yellow Sea and the former Saemangeum estuary.
The Salish Sea is a marginal sea of the Pacific Ocean located in the Canadian province of British Columbia and the U.S. state of Washington. It includes the Strait of Georgia, the Strait of Juan de Fuca, Puget Sound, and an intricate network of connecting channels and adjoining waterways.
The East Asian–Australasian Flyway is one of the world's great flyways of migratory birds. At its northernmost it stretches eastwards from the Taimyr Peninsula in Russia to Alaska. Its southern end encompasses Australia and New Zealand. Between these extremes the flyway covers much of eastern Asia, including China, Japan, Korea, South-East Asia and the western Pacific. The EAAF is home to over 50 million migratory water birds from over 250 different populations, including 32 globally threatened species and 19 near threatened species. It is especially important for the millions of migratory waders or shorebirds that breed in northern Asia and Alaska and spend the non-breeding season in South-East Asia and Australasia.
China's vast and diverse landscape is home to a profound variety and abundance of wildlife. As of one of 17 megadiverse countries in the world, China has, according to one measure, 7,516 species of vertebrates including 4,936 fish, 1,269 bird, 562 mammal, 403 reptile and 346 amphibian species. In terms of the number of species, China ranks third in the world in mammals, eighth in birds, seventh in reptiles and seventh in amphibians.
China’s coastline covers approximately 14,500 km from the Bohai gulf in the north to the Gulf of Tonkin in the south. Most of the northern half is low lying, although some of the mountains and hills of Northeast China and the Shandong Peninsula extend to the coast. The southern half is more irregular. In Zhejiang and Fujian provinces, for example, much of the coast is rocky and steep. South of this area the coast becomes less rugged: Low mountains and hills extend more gradually to the coast, and small river deltas are common.
China has one-fifth of the world's population and accounts for one-third of the world's reported fish production as well as two-thirds of the world's reported aquaculture production. It is also a major importer of seafood and the country's seafood market is estimated to grow to a market size worth US$53.5 Billion by 2027.
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The Yellow River Delta National Nature Reserve (YRDNNR) is a protected area in the city of Dongying, China, which covers wetland habitats on the shore of the Bohai Sea. These wetlands are formed through the deposition of silt by the Yellow River, forming a large and growing delta. The reserve is split geographically into two portions, one covering the current mouth of the Yellow River and one covering wetlands that remain near a former river mouth. In management terms, it is divided into a core area with a high level of protection, and buffer and experimental zones which allow for greater human activity.