Q. On the planet earth, most of the freshwater exists as ice caps and glaciers. Out of the remaining freshwater, the largest proportion (UPSC Prelims 2013)
Answer:
exists as groundwater
Notes: The correct answer is
[C] exists as groundwater.This is a frequently asked question because it challenges our intuition. While we see massive lakes and wide rivers, they represent only a tiny fraction of the Earth's total liquid freshwater.The Distribution of Water on EarthTo understand why groundwater is the largest "remaining" proportion, let's look at the breakdown of the Earth's water:
- Saline Water (Oceans): ~97.5%
- Freshwater: ~2.5%
Breakdown of that 2.5% Freshwater:
- Glaciers and Ice Caps: ~68.7% (The largest overall source, but frozen).
- Groundwater: ~30.1% (The largest proportion of "remaining" or liquid freshwater).
- Surface Water & Other: ~1.2% (This includes lakes, rivers, soil moisture, and atmospheric water).
Breakdown of Surface Water (The 1.2%):If we zoom into that tiny 1.2% of surface water, the distribution is even more surprising:
- Ground Ice & Permafrost: ~69%
- Lakes: ~20.9%
- Atmosphere: ~3%
- Rivers: ~0.49%
Why the other options are lower:
- [A] Atmosphere: Contains very little water at any given time (mostly as vapor).
- [B] Lakes and Rivers: Though they are our most visible sources, they hold less than 1% of the total freshwater.
- [D] Soil Moisture: While vital for agriculture, it is a very small volume compared to the vast aquifers underground.