Home › PYQs › World Geography › All questions › 2015 · Ocean currents
UPSC Prelims 2015 · World Geography · Oceans, Seas and Straits
What explains the eastward flow of the equatorial counter-current?
- (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
Show the answer and explanation
Answer: (b) Convergence of the two equatorial currents
The north and south equatorial currents push water west and pile it up on the western side. That water flows back east between them — the counter-current.
Why the others are wrong
(a) Rotation (Coriolis) deflects currents but doesn’t explain an eastward return flow along the equator.
(c) Salinity differences are too weak to drive it.
(d) The doldrums are calm, but calm air doesn’t push water east.
The trap
(d) sounds plausible because the counter-current runs under the doldrums. The calm only lets it flow — the push comes from the piled-up water.
🔒 Equatorial counter-current = return flow of water piled up in the west by the two westward equatorial currents.
Solve this chapter interactively →All World Geography questions