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Sea of Japan/East Sea

The Sea of Japan/East Sea is influenced by the warm Tsushima Current from the south and the cold Liman Current from the north, so its marine flora is a rich mix of temperate and cold-water species because of the wide range of water temperatures in different parts of the coast. The mixing of these currents also provides plentiful nutrients for plant growth. Seagrass diversity is moderate, but eelgrasses are particularly well represented with seven species, several of them endemic to the area. Kelps are also diverse, with species of Undaria, Laminaria, and Agarum thriving in the colder waters in the north. Kelp is highly nutritious, and Hokkaido is the traditional center of kelp harvesting.

Circulation within the Sea of Japan (also known as the East Sea) is counterclockwise, with warm water entering from the East China Sea through the Korea Strait. There are rich fishing grounds here and in the north. Squid are among the species sought by Japanese and Korean fishermen, who attract the animals to the surface at night using powerful lights. The continental shelf is slightly wider on the eastern side than on the western side, and particularly narrow off the coast of Korea. There are three main basins: the Yamato Basin in the east, the Japan Basin in the north, and the Tsushima Basin in the southwest. Between these basins lies the Yamato Ridge, possibly a remnant of the spreading center that opened up the sea. The Sea of Japan/East Sea is a geologically complex basin bisected by the junction between the Okhotsk Plate and the Eurasian Plate. In 1983, a magnitude-7.7 earthquake on the sea floor off northern Honshu triggered a destructive tidal wave that reached a height of 46 ft (14 m) at the coast, killing 107 people in Japan and Korea.

  • Pacific Ocean West
  • Coastal Type Mainly rocky
  • Water Type Warm to cold
  • Primary Vegetation Kelp and seagrasses
  • Location Off the west coast of the island of Hokkaido, northern Japan
  • Area 378,000 square miles (978,000 square km)
  • Maximum Depth 12,276 ft (3,743 m)
  • Inflows East China Sea; Tumen, Ishikari, Shinano, Agano, Mogami, Teshio rivers
Sea of Japan/East Sea habitat mapzoom image