The Global Water Cycle

Question 1

Why is the water cycle a closed system at a global scale?

Answer 1

Water is not gained or lost. It is transferred between flows.

Question 2

What are the global stores of water, and what percentage of the World’s water do they contain?

Answer 2

Oceans (97%)

Cryosphere (2%) - largest freshwater store, holding 69% of all fresh water

Groundwater (1.1%) - holds 30% of all fresh water

Rivers and lakes (0.01%)

Soils (0.015%)

Atmosphere (0.001%)

Biosphere (0.0004%)