5.1

Question 1

Why is the global hydrological cycle a closed system?

Answer 1

Its because there is no more water added or removed but constantly circulating between stores and flows.

Question 1

Where does water move through, throughout the water cycle?

Answer 1

biosphere- water held in living things
lithosphere- water held in rocks
atmosphere- water held in clouds
hydrosphere- water held in rivers and lakes

Question 2

Important percentages on stores of water….

Answer 2

oceans- 96.7%
freshwater- 2.5%
–> 0.45% of freshwater is drinkable

Question 3

What are the drivers of the hydrological cycle?

Answer 3

gravity- brings water down
solar energy- causes evaporation and evapotranspiration

Question 4

What does residence time mean?
Some examples…..

Answer 4

This is how long a molecule of water stays in a store
E.g. biosphere- 1 week
atmosphere- 1.5 week
ocean- 4000 years
groundwater- 2 weeks->
10,000 years
ice caps- 1->10,000 years

Question 5

What is fossil water?

Answer 5

ancient stores of freshwater
E.g. Kenya’s lotikipi aquifer store of fossil water has enough to supply Kenya for 70 years

Question 6

What is the cryosphere?

Answer 6

where water is frozen, so water is locked in glaciers and ice caps

Question 7

What is the global water budget?

Answer 7

Because water on the planet is finite, it limits the water available to humans

Question 8

What are the different stores and fluxes in the hydrological cycle?

Answer 8

stores:
- clouds
- groundwater
- vegetation
- streams
- snow and glaciers
- lakes
- ocean

flux:
- sublimation
- melt runoff
- soil moisture
- percolation (movement through permeable rock/ground)
- groundwater flow
- infiltration
- evaporation
- condensation
- precipitation