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Environmental Impact of the Tsushima Warm Current

Currents flowing around Japan and the environmental impact of the Tsushima Warm Current.

Oki has an unusual ecosystem. In Oki, various species that are normally distributed in different environments are found in the same place. There are many factors that have fostered this unique ecosystem, including geographical and climactic changes affecting Japan and Oki. One particular factor that has enabled species to exist outside of their regular habitats is the ‘Tsushima Warm Current’.

The Tsushima Warm Current flows around the Oki Islands from the south of the Japanese Archipelago. The warm air from this current collides with the cold northwesterly wind that blows over the Sea of Japan from the continent, and the evaporated air creates clouds. As a result the Sea of Japan region, including Oki, receives a high amount of rainfall, snow and fog. As Oki is a marine environment, the summers and winters are mild and there is rainfall all year round with high humidity. This mild, humid and wet environment is suitable for a wide variety of species.


  • Oki has a damp as well as a marine environment.
  • Tsushima Warm Current brings rain, snow and fog.
  • A wide variety of species can survive in the Oki climate.

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