Global Patterns of Water (AQA A Level Geography)

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

 

Global pattern of water scarcity

• 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