UPSC Prelims 2021 · Question 58 of 97
UPSC Prelims 2021 question on Ocean Temperature Patterns
- ExamUPSC CSE
- Year2021
- PaperGeneral Studies Paper I
- SubjectGeography
- TopicOceanography
- DifficultyMedium
- TypeStatement
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?
Show answer
Answer: C. Both 1 and 2
Verdict
Correct statements: Both 1 and 2 → Option (c).
Analysis
Mid-ocean surface temperatures vary with latitude in response to the balance between incoming solar radiation and outgoing longwave radiation. There is an excess of incoming solar radiation at latitudes less than approximately 45° and an excess of radiation loss at latitudes higher than approximately 45°.
The northward displacement of warm water to higher latitudes by the Gulf Stream of the North Atlantic and the Kuroshio (Japan Current) of the North Pacific creates sharp changes in temperature along the current boundaries or thermal fronts, where these northward-moving flows meet colder water flowing southward from higher latitudes.
Statement by statement
Statement 1 – CORRECT: At low latitudes the trade winds act to move water away from the lee coasts of the landmasses to produce areas of coastal upwelling of water from depth and reduce surface temperatures. This makes western sections warmer than the eastern sections in tropical zones.
Statement 2 – CORRECT: In the temperate zone, westerlies push warm water towards the eastern sections of the oceans, making them warmer than the western sections.