Global Patterns of Water (AQA A Level Geography)

Water Availability and Demand

Global Patterns of Water Availability and Demand

• Water is unevenly distributed around the globe

• There are significant areas of water surplus  and water deficit

• 450 million people in LICs suffer from severe water shortages

• 1.2 billion live in areas of water scarcity

• Physical water scarcity occurs where demand for water outstrips supply, often due to arid climate and low rainfall

• Economic water scarcity is where water is available but people can’t afford it or the infrastructure is inadequate

• The availability of water is affected by both physical and human factors

  • Physical factors influencing rainfall patterns include

    • Latitude

    • Wind direction

    • Proximity to coasts

• Human factors impact the ability of communities to collect and distribute clean water adequately

  •  Collection and distribution infrastructure such as wells, reservoirs, treatment plants, canals and pipelines

  • Overuse of water

  • Population growth increases demand and puts pressure on water systems

• There is a discrepancy between rural and urban areas, especially in LICs

  • 82% of those who lack access to clean water live in rural areas

• The greatest demand for water comes from HICs, especially in arid regions

  • UAE and North America have the highest per capita water usage globally

  • Water used for irrigation of crops 

  • As well as for domestic appliances such as dishwashers and washing machines

  • Also extracted for recreational use, e.g. swimming pools and golf courses

• Sub-Saharan Africa has the lowest per capita usage

  • Unreliable rainfall supply in some regions, e.g. the Sahel

  • Poor water infrastructure in areas where natural supply is high, e.g. equatorial belt of central Africa