Question 14
AOptions
BSolution
The Equatorial Counter-Current, or Equatorial Undercurrent, is an eastward-flowing current found near the equator in the Pacific, Atlantic, and Indian Oceans. This current flows against the prevailing westward flow of the North and South Equatorial Currents. Its eastward flow is primarily explained by the accumulation of water in the western part of the ocean basin due to the continuous push of the westward-flowing equatorial currents by the trade winds. This piling up of water creates a hydrostatic pressure gradient, where the sea level is slightly higher in the west. This pressure gradient then drives the water back eastward as a counter-current in the absence of strong Coriolis deflection at the equator. While other factors might subtly influence ocean currents, the convergence and resulting pressure gradient due to the two equatorial currents is the primary mechanism for the eastward counter-current.
CStrategy
For questions on oceanography and atmospheric phenomena, understand the fundamental physical principles (e.g., pressure gradients, Coriolis effect, wind stress). Visualize how different forces interact to create the observed phenomena. Focus on the primary drivers rather than secondary or minor influences.
DSyllabus Analysis
This question falls under the Geography section, specifically Oceanography, dealing with ocean currents and their dynamics.
EQuestion Analysis
Difficult. This question requires a detailed understanding of the complex dynamics of ocean currents and the specific mechanisms driving the equatorial counter-current.