REVISION AS CAMBRIDGE GEOGRAPHY: RIVERS - GLOBAL HYDROLOGICAL CYCLE.

1. AS GEOGRAPHY
HYDROLOGY
4 QUESTIONS
REVISION
GLOBAL
HYDROLOGICAL
CYCLE

2. QUESTION 1
In what three states can water exist?

3. ANSWER
Liquid (water droplets), solid (ice), gaseous (water vapour).

4. QUESTION 2
What is evaporation?

5. ANSWER
The change of state from water droplets to water vapour.

6. QUESTION 3
Which process changes water vapour into water droplets?

7. ANSWER
Condensation.

8. QUESTION 4
What percentage of the water in the cycle is stored in seas and oceans?

9. ANSWER
About 97%.

10. IMPORTANT
The global hydrological cycle is a “closed system” as it has no external
inputs or outputs of water. There is a fixed amount of water in the
system and this cannot change.
However, the percentage of water in each of the three states can vary
over time.
For example, global warming might result in there being more water in a
liquid state as ice sheets melt.