We can think of several different kinds of resource scarcity.
- Absolute scarcity: First, it may be that there are simply insufficient quantities of a resource to meet human needs or wants. We call this absolute scarcity. No matter how much we look or try to find additional sources, there are none to be had. Lack of food leads to starvation, lack of water leads to drought, thirst, and crop failure – and starvation. There simply is no food or water to be had, at least in that particular area.
- Relative scarcity: Second, there may be physical quantities of a resource present but scarcity exists because of problems about supply or distribution. Meeting the demand for that resource might mean exploiting lower quality resources. For example, food production may require cultivating lands that are poorly suited to farming, such as on steep slopes or in very arid areas, requiring a greater effort (more labour) and other inputs (chemical fertilizers, irrigation) in order to meet the demand. Another example concerns the exploitation of fossil fuels. When the most accessible and best quality fuels are fully exploited (e.g., sweet crude from the Middle East or other areas) we may turn to lower quality fuels (tar sands) to meet our needs.