UPSC Prelims 2002 Q82: Geography – Oceanography
Consider the following statements:
1. Ocean currents are the slow surface movement 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 floor.
Which of these statements are correct?
- (a) 1 and 2
- (b) 2, 3 and 4
- (c) 1, 3 and 4
- (d) 1, 2, 3 and 4
Answer: (d) 1, 2, 3 and 4
Explanation
Ocean currents: properties and causes
| Statement | Verdict |
|---|---|
| 1. Ocean currents are slow surface movements of water | True — they move at a few km/h |
| 2. They help maintain the Earth's heat balance | True — carry heat from the tropics to the poles |
| 3. They are set in motion primarily by prevailing winds | True — wind drag is the main force |
| 4. They are affected by the configuration of the ocean floor | True — coastlines and the sea floor deflect them |
All four statements are correct. Ocean currents are slow movements of surface water, driven mainly by prevailing winds, deflected by coasts and the sea floor, and they redistribute heat, so the answer is 1, 2, 3 and 4.
Answer: (d) 1, 2, 3 and 4.
Why each option is right or wrong
- (a) Incorrect. It omits statements 3 and 4, which are also true.
- (b) Incorrect. It omits statement 1, which is also true.
- (c) Incorrect. It omits statement 2, which is also true.
- (d) CORRECT. All four statements are true.
Key point
Forces behind currents: planetary winds, Coriolis effect, temperature and salinity differences, land masses.
Remember
Currents: wind driven, deflected by land and sea floor, redistribute heat.
Common mistakes
- Dropping statement 1 because 'slow' seems odd for currents.
- Forgetting the role of ocean-floor shape and coasts.
- Ignoring the role of currents in the Earth's heat balance.
Exam tip
If every statement is a standard textbook fact, choose all of them.
Sources
- NCERT Class XI Geography — Fundamentals of Physical Geography — Movements of Ocean Water
- G. C. Leong — Certificate Physical and Human Geography (Ocean Currents)