2.3.6. Currents of the Atlantic Ocean

Major currents of the Atlantic Ocean are:

North and South Equatorial Current

♤ To the north and south of the equator, there are two westward moving currents-the North Equatorial Current and the South Equatorial Current.

♤ Due to the rotation of the Earth (Coriolis Effect), these currents move almost due west along the equator.

♤ The North Equatorial Current moves northwards due to the presence of the South American continent and the Coriolis force, and takes the north-west direction. It enters the Gulf of Mexico to form the Gulf Stream.

♤ The South Equatorial Current originates from the western coast of Africa, from where it moves towards South America.

♤ The east coast of Brazil obstructs the South Equatorial Current which then bifurcates into two branches.

♤ The northward branch merges with the North

♤ Equatorial Current, while the second branch flows along the east coast of Brazil and is known as the Brazilian Current.

♤ The North Equatorial Current and the South Equatorial Current are warm currents.

Gulf Stream

♤ The Gulf Stream is one of the largest warm currents. It originates from the Gulf of Mexico (about 20° N) and moves in a north-easterly direction along the eastern coast of North America.

♤ The average speed is about 33 km per day and its average width is about 70 km.

♤ Under the impact of the Westerlies, this warm current reaches the western coast of Europe (about 70° N latitude).

♤ The general direction of flow of the Gulf Stream, north of 30° N latitude, is northward.

♤ Near Newfoundland, its water mixes with the cold water of the Labrador Current, which forms very dense fog. The foggy conditions around Newfoundland hamper the navigation of ships.

♤ From here, the Gulf Stream moves northeastwards.

♤ This current gradually widens and its speed decreases. It becomes a prominent, slow- moving current known as the North Atlantic Drift.

♤ Near Western Europe, it splits into two parts. One part moves northwards, past UK and Norway, while the other part is deflected southwards as the cold Canary Current.

♤ The warm water of the Gulf Stream modifies the weather conditions off the eastern coast of North America and the western coast of Europe.

♤ On the western coast of Europe, the seaports remain open even in the severe winter season due to the warm water of the Gulf Stream.

Labrador Current

♤ The cold Labrador Current of the North Atlantic Ocean, has its origin in the Arctic Ocean.

♤ This current flows from north to south between Greenland and the Baffin islands.

♤ The Labrador Current merges with the Gulf Stream near Newfoundland.

♤ This helps in the growth of plankton- a feed for fish. Thus the Grand Banks near Newfoundland have become the ideal fishing ground in the world.

♤ The average speed of the Labrador Current is about 25 km per day.

♤ This current brings huge icebergs with it from the Arctic Ocean.

Canary Current

♤ The Canary Current is a cold current and flows along the western coast of Spain and Portugal and the north-west coast of North Africa. .

♤ The average speed of this current is about 45 km per day.

♤ The relative coolness of the Canary Current reduces the relative humidity and thus causes scanty rainfall in the greater parts of the Sahara Desert.

Brazil Current

♤ The Brazil Current is a warm current and flows southward along the east coast of South America (about 40° S latitude).

♤ The average speed of the Brazil Current is about 30 km per day.

♤ From 40° S, it is deflected eastwards due to the Earth's rotation and flows in easterly direction.

♤ It modifies the weather conditions along the eastern coasts of Brazil and Argentina.

Falkland Current

♤ The cold waters of the Antarctic Sea flow as Falkland Current from south to north along the eastern coast of South America up to Argentina.

♤ The Falkland Current brings huge icebergs from the Antarctic region to the South American coast.

Benguela Current

♤ The Benguela Current is a cold current which originates in the Antarctic region and flows along the coast of south-west Africa.

♤ The Benguela Current helps in reducing the relative humidity of the eastward moving warm and moist air masses.

♤ The Kalahari Desert is largely formed under the influence of this current.

♤ Further northwards, the Benguela Current merges with the South Equatorial Current.

South Atlantic Drift

♤ The eastward continuation of the Brazil Current is called the South Atlantic Drift or the West Wind Drift.

♤ It develops at about 40° S latitude due to the impact of the Westerlies.

♤ The eastward movement is due to the Earth's rotation.