Relationship Of Water Supply To Physical Geography

Question 1

How does climate affect water supply?

Answer 1

• Water storage and precipitation are greatest in winter and autumn
• El Nino events may decrease water supply in some areas
• Storm events are becoming less effective at recharging groundwater stores

Question 2

How does drainage density affect water supply?

Answer 2

1. The greater the number of rivers in an area helps to ensure a consistent water supply
   Example: in the Nile basin where water sourced from mountainous areas of Ethiopia and other African countries, droughts upstream can decrease supplies downstream.

Question 3

How does surface water stores affect water supply?

Answer 3

• Provides the most accessible water supply
• Water quality is more likely to be affected by sediment/contamination
• Evaporation is greater as global temperatures rise by degrees celsius

Question 4

How do evaporation rates affect water supply?

Answer 4

• Higher temperatures leads top increased evaporation rates which reduces water supply
  Example: Aswan Dam loses 7.4mm per day through evaporation but only gains 5mm of rainfall every month.

Question 5

How does geology affect water supply?

Answer 5

• Permeable rocks can be infiltrated and water can be stored underground in an acquifer to provide a long-term water store (this water is high quality as it is filtered through rock)
• If the ground is impermeable, surface storage is more important and there is a high risk of drought (surface stores are lower quality due to greater pollution and eutrophication risks)
• Mountainous regions encourage relief rainfall (increase supply) but can also create a rain shadow (reduce water supply)

Question 6

Describe the UK drought 1976.

Answer 6

1. 143 litres consumed daily
2. Industrial sector told to cut water usage by 50% (very difficult for power stations)
3. Unnecessary water use such as hose pipes was banned