(a) The Earth’s rotation on its axis
(b) Convergence of the two equatorial currents
(c) Difference in salinity of water
(d) Occurrence of the belt of calm near the equator
Answer: (b)
Option (b) is correct: Convergence of the two equatorial currents is the reason behind the eastward flow of the equatorial counter-current.
O Equatorial counter-currents are major surface flows that carry water eastward in the Atlantic, Indian, and Pacific Oceans. They are located near the equator and are sandwiched between two westward flowing currents, the North Equatorial Current and the South Equatorial Current. Equatorial counter-currents are unique in that they flow in the opposite direction of the surface winds. The other major surface currents in the tropics flow in the same direction as the prevailing winds.
O The equatorial counter-currents are driven by a distinct surface wind pattern in the tropics. Strong westward trade winds result in westward surface flow in most of the tropical Atlantic and Pacific Oceans. The stronger winds to the south pile up water where the winds are weak. The excess water flows eastward under the influence of the Earth’s rotation, giving rise to equatorial counter-currents.
