Water scarcity and security
Big idea: Water security means having reliable access to enough clean water. When demand exceeds supply, we have water scarcity — and billions of people face this daily.
Types of water scarcity
Physical scarcity
- Not enough water exists in the region
- Caused by: arid climate, drought, overuse
- Examples: Middle East, North Africa, Australia
- Solutions: desalination, water transfer, efficiency
Economic scarcity
- Water exists but people cannot access it
- Caused by: poverty, lack of infrastructure, poor governance
- Examples: Sub-Saharan Africa, parts of Asia
- Solutions: investment, infrastructure, governance
Factors increasing water stress
- Population growth — more people = more demand
- Economic development — higher living standards = more water use
- Climate change — changing precipitation, more droughts/floods
- Pollution — contamination reduces usable supply
- Urbanization — concentrated demand, infrastructure strain
For longer responses about water scarcity, define water security and scarcity first, then compare physical vs economic scarcity. Add drivers (population, development, climate change, pollution) and finish with a balanced conclusion that considers both conflict and cooperation.
IB-style question — how climate change worsens scarcity [2]
A map shows water scarcity rising in many mid-latitude countries by 2040. Identify two ways climate change could cause this increase in water scarcity. [2]
How to answer it, step by step
- {"label":"**One mark per distinct way**","body":"**Pick changes that cut usable freshwater**<br>• Shifting rainfall patterns reduce supply in some regions<br>• Hotter temperatures raise evaporation, drying rivers and reservoirs"}
- {"label":"**Another valid route**","body":"**Ice and seas also matter**<br>• Melting glaciers first boost, then cut, river flow<br>• Rising seas push salt into coastal freshwater (salinisation)"}
Final answer
Give two different mechanisms — link each clearly to less usable freshwater, not just 'climate change is bad'.