How Deep Ocean Currents Shape the World’s Climate
Check out the diagrams below to find out exactly how the different ocean currents in the world affect the world's climate
The Kuroshio Current
- A north-flowing ocean current on the west side of the North Pacific Ocean.
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Similar to the Gulf Stream in the North Atlantic and part of the North Pacific Ocean gyre.
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Begins off the east coast of Luzon, Philippines, passing Taiwan and flowing northeastward past Japan, where it merges with the easterly drift of the North Pacific Current.
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Its warm waters sustain the coral reefs of Japan, the world’s northernmost coral reefs.
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A branch off from the Kuroshio into the Sea of Japan is called the Tsushima Current.
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The Kuroshio and Tsushima are responsible for the mild weather experienced around Alaska’s southern coast and in British Columbia.
The Oyashio Current
- A cold subarctic ocean current that flows south and circulates counterclockwise in the western North Pacific Ocean (also known as Oya Siwo, Okhotsk or the Kurile CURRENT)
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Originates in the Arctic Ocean and flows southward via the Bering Sea, passing through the Bering Strait and transporting cold water from the Arctic Sea into the Pacific Ocean.
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Collides with the Kuroshio off the eastern shore of Japan to form the North Pacific Current (or Drift).
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A nutriet-rich current that is named for its metaphorical role as the parent that provides for and nurtures marine organisms.
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Has an important impact on the climate of the Russian Far East, mainly in Kamchatka & Chukotka, where the northern limit of tree growth is moved south up to 10o compared with the̊ latitude it can reach in inland Siberia.
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Forms probably the richest fishery in the world, owing to the extremely high-nutrient content of the cold water and the very high tides (up to 10 M) in some areas – which further enhance the availability of nutrients.
The Agulhas Current
- the western boundary current of the southwest Indian Ocean. It flows down the east coast of Africa.
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narrow, swift and strong. It is even suggested that the Agulhas is the largest western boundary current in the world ocean.
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The sources of the Agulhas are the East Madagascar Current, the Mozambique Current and a recirculated part of the southwest Indian subgyre south of Madagascar.
The East Australian Current (EAC)
- The southward western boundary current that is formed from the South Equatorial Current (SEC) crossing the Coral Sea and reaching the eastern coast of Australia.
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The largest ocean current close to the shores of Australia.
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The majority of the EAC flow that does not recirculate will move eastward into the Taman Front crossing the Tasman Sea just north of the cape of New Zealand.
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The eastward movement of the EAC through the Tasman Front and reattaching to the coastline of New Zealand forms the East Auckland Current.
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Also acts to transport tropical marine fauna to habitats in subtropical regions along the southeast Australian coast.
The Indonesian Throughflow (ITF)
- An ocean current with importance for global climate, providing a low-latitude pathway for warm, fresh water to move from the Pacific to the Indian Ocean
- Serves as the upper branch of the global heat conveyor belt
- Higher ocean surface topography in the western Pacific than in the Indian Ocean drives upper thermocline water from the North Pacific through the western route of the Makassar Strait to either directly exit through the Lombok Strait or flow eastward into the Banda Sea
- Weaker flow of saltier and denser South Pacific water passes over the Lifamatola Passage into the Banda Sea, where these water masses are mixed due to tidal effects, among other aspects
- From the Banda Sea, the ITF exits Timor, Ombai and Lombok passages
- Circulation and transport within the Indonesian Seas varies along with large-scale monsoon flow
DID YOU KNOW?
The sverdrup (Sv), named in honour of the pioneering Norwegian oceanographer Harald Sverdrup, is a unit of measure of volume transport. It is used almost exclusively in oceanography to measure the volumetric rate of transport of ocean currents.
The water transport in the Gulf Stream gradually increases from 30 Sv in the Florida Current to a maximum of 150 Sv south of Newfoundland. The heat carried within this volume equals roughly that transported through the atmosphere to make the relatively milder climate of northwestern Europe. The Antarctic Circumpolar Current, at approximately 125 Sv, is the largest ocean current.
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