Q. Consider the following statements:- In the tropical zone, the western sections of the oceans are warmer than the eastern sections owing to the influence of trade winds.
- 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? (UPSC Prelims 2021)
Answer:
Both 1 and 2
Notes: The correct answer is
[C] Both 1 and 2. This question examines the relationship between prevailing wind systems and the distribution of ocean surface temperatures across different latitudinal zones.
- Tropical Zone (Statement 1 – Correct): In the tropics (between the equator and 30°), Trade Winds blow from east to west. These winds push warm surface waters toward the western margins of the oceans (e.g., the western Pacific near Indonesia). Simultaneously, they cause upwelling of cold deep-sea water along the eastern margins (e.g., the coast of Peru), making the western sections significantly warmer than the eastern sections.
- Temperate Zone (Statement 2 – Correct): In the mid-latitudes (30° to 60°), the prevailing winds are the Westerlies, which blow from west to east. These winds carry relatively warmer water from the western side of the basin toward the eastern sections (e.g., the North Atlantic Drift warming the coasts of Western Europe). Consequently, the eastern sections of the oceans in these zones are warmer than the western sections, which are often influenced by cold currents moving from higher latitudes.
This temperature gradient is a fundamental driver of global climate phenomena. In the tropics, this imbalance is central to the
Walker Circulation and the
El Niño-Southern Oscillation (ENSO) cycle, which can periodically reverse these typical temperature patterns.