Oceanography : Movements Of Ocean

Q 7 / 11

UPSC CSE Prelims 2002

Consider the following statements:

  1. Ocean currents are slow surface movements of water in the ocean.
  2. Ocean currents assist in maintaining the Earth's heat balance.
  3. Ocean currents are set in motion primarily by prevailing winds.
  4. Ocean currents are affected by the configuration of the ocean.

Which of these statements are correct?

EXPLANATION

Correct Option (b):

Statements 2, 3, and 4 are correct.

  • Statement 2: Ocean currents play a crucial role in the global redistribution of heat. They transport warm water from equatorial regions towards higher latitudes and cold water from polar regions towards the equator, thereby moderating global temperatures and contributing to the Earth's overall heat balance.
  • Statement 3: The primary driving mechanism for most surface ocean currents is the frictional drag exerted by prevailing winds (e.g., trade winds, westerlies) on the ocean surface.
  • Statement 4: The configuration of ocean basins, including the shape and position of continents, coastal morphology, and submarine topography (such as mid-oceanic ridges and varying depths), significantly influences the direction, intensity, and pathways of ocean currents by deflecting and channeling their flow.

Incorrect Options

Statement 1 is incorrect.

  • Statement 1: Ocean currents are not exclusively slow movements or confined to the surface layers. They exhibit a wide range of speeds, and significant deep-ocean currents, such as those driven by thermohaline circulation, exist below the surface and play a vital role in global ocean circulation. Therefore, this statement provides an incomplete and partially inaccurate description.

Options (a), (c), and (d) are incorrect because they include Statement 1, which is inaccurate.

SOURCECertificate Physical and Human Geography by G.C. Leong, Chapter 18: Ocean Currents