Water scarcity is a major issue studied in IB Geography, particularly within Option A: Freshwater – Drainage Basins. Water scarcity occurs when the demand for water exceeds the available supply, either physically or economically. It is a growing global challenge influenced by a combination of physical factors and human activities.
One of the most important physical causes of water scarcity is climate. Arid and semi-arid regions receive low and unreliable rainfall, limiting natural water availability. Extended droughts further reduce river discharge, groundwater recharge, and reservoir levels. Climate change is intensifying this problem by increasing temperatures and altering rainfall patterns, making water supplies more unpredictable.
Seasonal variability also contributes to water scarcity. In many regions, rainfall is concentrated in a short wet season, while long dry seasons place pressure on water resources. Without sufficient storage infrastructure, excess water from the wet season cannot be saved for use during dry periods, increasing scarcity.
Human factors play an even greater role in causing water scarcity. Over-extraction of water for agriculture, industry, and domestic use reduces river flows and groundwater levels. Agriculture is the largest user of freshwater globally, particularly for irrigation. Inefficient irrigation methods and water-intensive crops significantly increase water demand, especially in dry regions.
Population growth and urbanisation increase water demand further. Growing populations require more water for drinking, sanitation, food production, and energy generation. Rapid urban growth can strain water supply systems, particularly in low-income countries where infrastructure development cannot keep pace with demand.
Water scarcity is also caused by pollution. Industrial waste, agricultural runoff, and untreated sewage contaminate rivers, lakes, and groundwater, making water unsafe for use. Pollution reduces the amount of usable freshwater available, effectively creating scarcity even in regions with adequate physical water supplies.
In IB Geography, it is important to distinguish between physical water scarcity and economic water scarcity. Physical scarcity occurs when natural water supplies are insufficient. Economic scarcity occurs when water exists but people cannot access it due to poor infrastructure, lack of investment, or weak governance. Many low-income countries experience economic water scarcity despite having abundant water resources.
Political and management factors also contribute. Poor water governance, lack of regulation, and unequal distribution can increase scarcity. Conflict over shared water resources may further restrict access and worsen shortages.
Overall, water scarcity is caused by a complex interaction of climate, overuse, pollution, population growth, and management issues. Understanding these causes is essential for evaluating water security and management strategies.
RevisionDojo helps IB Geography students understand water scarcity clearly by linking physical processes and human pressures into structured, exam-ready explanations.
