UPSC Prelims 2010 Q73: Geography – Oceanography
Consider the following statements:
1. On the planet Earth, the fresh water available for use amounts to about less than 1% of the
total water found.
2. Of the total fresh water found on the planet Earth 95% is bound up in polar ice caps and
glaciers.
Which of the statements given above is/are correct?
- (a) 1 only
- (b) 2 only
- (c) Both 1 and 2
- (d) Neither 1 nor 2
Answer: (a) 1 only
Explanation
Earth's fresh water: checking two statements
Only a tiny fraction of Earth's total water is fresh and usable, and most of that fraction is frozen.
| Statement | Verdict | Reason |
|---|---|---|
| 1. Fresh water available for use is less than about 1% of total water | Correct | Of Earth's total water, only a tiny fraction (under ~1%) is readily usable fresh water (rivers, lakes, accessible groundwater) |
| 2. Of total fresh water, 95% is in polar ice caps/glaciers | Incorrect | The commonly cited figure is that about ~68-70% of fresh water is locked in ice caps/glaciers, not 95% — this figure overstates it |
Earth's water distribution:
| Point | Detail |
|---|---|
| Usable fresh water | Less than ~1% of total water |
| Fresh water locked in ice | ~68-70%, not 95% |
| Rest | Groundwater, lakes, rivers, atmosphere |
Answer: (a) 1 only.
Why each option is right or wrong
- (a) CORRECT. The usable fresh water figure (under ~1% of total water) is accurate; the 95%-in-ice claim overstates the real figure.
- (b) Incorrect. 95% overstates the actual share of fresh water locked in polar ice/glaciers (closer to ~68-70%).
- (c) Incorrect. Statement 2 is inaccurate, so 'both' cannot be correct.
- (d) Incorrect. Statement 1 is accurate, so 'neither' is wrong.
Key point
Usable fresh water is indeed under about 1% of Earth's total water — but only about 68-70% (not 95%) of total fresh water is locked in polar ice caps and glaciers.
Remember
Usable fresh water is under ~1% of Earth's total water; about 68-70% (not 95%) of total fresh water is locked in polar ice/glaciers.
Common mistakes
- Overstating the share of fresh water locked in ice as 95%, when the commonly cited figure is closer to 68-70%.
- Confusing 'usable fresh water' (a small fraction of all water) with the share of fresh water that is frozen.
- Not distinguishing between these two separate statistics about Earth's water.
Exam tip
Usable fresh water: under ~1% of total water. Fresh water locked in ice: ~68-70%, NOT 95%. Two separate numbers — don't mix them up.
Sources
- United States Geological Survey — The Distribution of Water on, in, and above the Earth
- Central Water Commission — Water and Related Statistics