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OCEAN CURRENTS

3rd September, 2021 Prelims

Introduction

  • Ocean currents are the continuous, predictable, directional movement of seawater driven by gravity, wind (Coriolis Effect), and water density.
  • Ocean water moves in two directions: horizontally and vertically.
  • Horizontal movements are referred to as currents, while vertical changes are called upwellings or downwellings.

List of Cold Currents

Cold Ocean Current

Region

Important or Additional Facts

Humboldt or Peruvian Current

South Pacific Ocean

  • The Current is named after Prussian naturalist Alexander Von Humboldt.
  • This low-salinity current has a large marine eco-system serves as one of the major nutrient systems of the world.
  • Flows from the southernmost tip of Chile to northern Peru, along the west coast of South America.

Kurile or Oya shio Current

North Pacific Ocean

  • This sub-arctic ocean current circulates in a counterclockwise direction.
  • It originates in the Arctic Ocean flows south via the Bering Sea in the western North Pacific Ocean.
  • It is a nutrient-rich current.
  • It collides with Kurioshio off the Japanese eastern shore to form North Pacific Drift.

California Current

Pacific Ocean

  • It is the extension of Aleutian Current along the west coast of North America in southward flowing direction.
  • It is a part of North Pacific Gyre.
  • Region of strong Upwelling.

Antarctic Circumpolar Current

Southern Ocean

  • It is the largest ocean current in the world.
  • It is also known as West Wind Drift.
  • It flows from east to west around Antarctica in a clockwise direction.

Labrador Current

North Atlantic Ocean

  • It flows from the Arctic Ocean towards the south and meets the warm northward moving Gulf Stream.
  • The combination of cold Labrador Current and warm Gulf Stream is known for creating one of the richest fishing grounds of the world.

Canary Current

North Atlantic Ocean

  • This Eastern Boundary Current is a part of North Atlantic Gyre.
  • It is named after the Canary Islands.
  • Presence of Upwelling.

Eastern Greenland Current

Arctic Ocean & North Atlantic Ocean

  • Low salinity current extending between Fram Strait and Cape Farewell.
  • It connects the Arctic directly to North Atlantic.
  • Major freshwater sink for the Arctic.
  • It is a major contributor to sea-ice export out of Arctic.

Benguela Current

South Atlantic Ocean

  • Branch of West Wind Drift of the Southern Hemisphere.
  • Eastern portion of South Atlantic Ocean Gyre.
  • Low salinity, presence of upwelling- excellent fishing zone.

Falkland Current

South Atlantic Ocean

  • It is a branch of Antarctic Circumpolar Current.
  • It is also known as Malvinas Current.
  • It is named after the Falkland Islands.
  • This cold current mixes with warm Brazil current and form Brazil-Malvinas Confluence Zone which is responsible for the region’s temperate climate.

Northeast Monsoon Current

North Indian Ocean

  • Indian North Equatorial Current flows southwest and west, crossing the Equator.

Somali Current

West Indian Ocean

  • Analogous to the Gulf Stream in the Atlantic Ocean.
  • The Current is heavily influenced by monsoon.
  • Region of major upwelling system.

Western Australian Current

Southern Ocean & South Indian Ocean

  • It is also known as West Wind Drift.
  • It is a part of Antarctic Circumpolar Current.
  • It is a seasonal current- strong in summer and weak in winter.

South Indian Ocean Current

South Indian Ocean

  • Analogous to South Atlantic Current.

List of Warm Currents 

List of Warm Warm Ocean Current

Region

Important or Additional Facts

North Equatorial Current

Pacific Ocean & Atlantic Ocean

  • Flows east to west between 10° N to 20°N.
  • It forms the southern side of the clockwise sub-tropical gyre.
  • It has no relation with the equator despite the term “equatorial” being used in its name.

Kuroshio Current

Pacific Ocean

  • This west boundary current is also known as Japan Current or Black Current. The term “Kuroshio” in Japanese means “Black Stream”.
  • It is the Pacific analogue of Gulf Stream in the Atlantic Ocean.
  • The average surface temperature of this current is warmer than the surrounding ocean. This also helps in regulating the temperature of Japan, which is relatively warmer. Thanks to Kuroshio!

North Pacific Current

Pacific Ocean

  • It is formed by the collision of Kurioshio & Oyashio.
  • It circulates counter-clockwise along the Western North Pacific Ocean.

Alaskan Current

North Pacific Ocean

  • It results from a northward diversion of a part of the North Pacific Ocean.
  • It forms two large eddies- Haida Eddies and Sitka Eddy

Equatorial Counter Current

Atlantic Ocean, Pacific Ocean, and the Indian Ocean

  • This wind-driven current flows west to east between 3°N-10°N.
  • It is also called North Equatorial Countercurrent.

El Nino Current

Central & East-Central Equatorial Pacific

  • Speed and strength of ocean currents impacted by the occurrence of El Nino events.

Tsushima Current

Sea of Japan

  • Branch of Kuroshio Current

South Equatorial Current

Atlantic Ocean, Pacific Ocean, and the Indian Ocean

  • Directly driven by trade winds blowing from east to west.
  • Southern hemisphere counter-part of North Equatorial countercurrent.

East Australian Current

South-Western Pacific Ocean

  • Acts to transport tropical marine fauna to habitats in sub-tropical regions along the southeast Australian coast.

Florida Current

South Atlantic Ocean & Caribbean Sea

  • Flows around Florida Peninsula and joins the Gulf Stream at Cape Hatteras.
  • Discovered in 1513 by Spanish explorer Juan Ponce de León.

Gulf Stream

North Atlantic Ocean

  • Western intensified current-driven mainly by wind stress.
  • It splits into North Atlantic Drift (crossing Northern Europe & southern stream) and Canary Current (recirculating of West Africa).

Norwegian Current

North Sea (Atlantic Ocean) & Barents Sea (Arctic Ocean)

  • This wedge-shaped current is one of the two dominant Arctic inflows of water.
  • It is a branch of North Atlantic Drift and sometimes also considered as an extension of the Gulf Stream.

Irminger Current

North Atlantic Ocean

  • It is a part of the North Atlantic sub-polar gyre.
  • It is named after the Danish vice-admiral Carl Ludvig Christian Irminger.

Antilles Current

North Atlantic Ocean

  • It flows past the island chain that separates the Atlantic Ocean and the Caribbean Sea.
  • It is a part of North Atlantic gyre.

Brazilian Current

South Atlantic Ocean

  • Flows along the south coast of Brazil till Rio de la Palta.
  • It joins cold Falkland Current at the Argentine Sea making it a temperate sea.

Mozambique Current

Indian Ocean

  • Flows between Mozambique and the island of Madagascar along the African east coast in the Mozambique Channel.
  • Large anticyclonic Mozambique channel eddies are formed.

Agulhas Current

South-West Indian Ocean

  • Largest western boundary ocean current.
  • Flows south along the east coast of Africa.

Southwest Monsoon Current

Indian Ocean

  • It dominates the Indian Ocean during the southwest monsoon season (June–October).
  • It is a broad eastward flowing ocean current that extends into the Arabian Sea and Bay of Bengal.

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