Water world Flashcards
Define the hydrological cycle
A closed system of water movement between stores
Define a closed system
Where no water can enter or exit the system/cycle
Define a drainage basin
The area drained by a river and it’s tributaries
What processes return water to the oceans?
Surface run-off (rivers) due to impeccable rock and intense rainfall
Groundwater flow through unsaturated permeable rock due to percolation
Define Infiltration
Vertical movement of water into soil
Define percolation
Vertical movement of water through permeable rock
Define what the aquifer is
Saturated rock which acts as a groundwater storage
What does groundwater flow through?
Unsaturated permeable rock
When does surface run-off occur?
When the rock is impermeable or saturated
How does water transfer from earth into the atmosphere?
Evapotranspiration
Define what evapotranspiration is
Sum of evaporation from the oceans and transpiration from vegetation to transfer water from the earth’s surface to the atmosphere
Define interception in the hydrological cycle
Blockage or slowing of the transfer of water from the atmosphere to the earth’s surface by vegetation
define drip flow
The transfer of water from precipitation to soil by vegetation
What is a depression storage?
A puddle - a temporary store
Define through flow
Flow of water horizontally through soil
Define transpiration
Transfer of water from vegetation to the atmosphere through the stomata by photosynthesis
Define stem flow
Transfer of intercepted precipitation via tree trunks
What is water stress?
When demand for water exceeds the supply for a certain period OR when the quality of water isn’t good enough
What is Physical water scarcity?
When the demand always exceeds the supply OR the quality of water is never good enough for everyone to have enough water
What is Economic water scarcity?
When people can’t afford the water even if it’s readily available
Why is there water scarcity?
Global warming - more evaporation less water
Melting of glaciers - fresh water turning into sea water which isn’t drinkable
Industrialisation which uses lots of water
How can human activity disrupt water supply?
Dams - reduce quantity of water downstream
Deforestation can reduce precipitation levels
Unreliable rainfall patterns due to climate change
Industrial, agricultural and domestic waste can contaminate important water sources
Why is there a higher demand for water?
Rising demand in emerging economies from industry through industrialisation
High demand for generating electricity
Rising demand for food in developing world - greater irrigation is needed for intensive agriculture
Domestic demand increases as water is piped to homes in developing countries - used more frequently
Greater disposable incomes - buy appliances that require water (washing machines) and water garden
People shower and wash more
Population growth in LEDC’s
Why is the physical scarcity of water increasing?
Enhanced greenhouse effect - oceans warm - greater melting of glaciers that contain fresh water
Increasing drought from less rainfall
More extreme weathering North Hemisphere like flooding which leads to a loss of fresh water
