Oceanography : Oceans

Q 4 / 11

UPSC CSE Prelims 2021

Consider the following statements:
  1. In the tropical zone, the western sections of the oceans are warmer than the eastern sections owing to the influence of trade winds.
  2. In the temperate zone, westerlies make the eastern sections of oceans warmer than the western sections.
Which of the statements given above is/are correct?

EXPLANATION

Correct Option (c)

Explanation

Both statements 1 and 2 are correct.

Statement 1: In the tropical zone, trade winds blow consistently from east to west. These winds exert a drag on the ocean surface, pushing warm surface water from the eastern parts of the ocean basins towards the western margins. This accumulation of warm water leads to higher sea surface temperatures in the western sections compared to the eastern sections. A notable example is the Western Pacific Warm Pool.

Statement 2: In the temperate zone, westerlies are the dominant winds, blowing from west to east. These winds influence the movement of ocean currents, transporting warm water from lower latitudes towards the eastern sections of ocean basins. For instance, the North Atlantic Drift, influenced by westerlies, carries warm water towards Western Europe, making the eastern North Atlantic Ocean warmer. Conversely, the western sections of oceans in temperate zones often experience cooler currents flowing from higher latitudes or upwelling, contributing to lower temperatures. Thus, westerlies contribute to making the eastern sections of oceans warmer than their western counterparts in these latitudes.

Incorrect Options

Options (a), (b), and (d) are incorrect because both statements 1 and 2 accurately describe the influence of prevailing winds on ocean temperatures in their respective climatic zones.

SOURCENCERT Class 11 Geography Chapter 13: Water (Oceans), Certificate Physical and Human Geography by G.C. Leong, Chapter 14: Ocean Currents