EESA07H3 Chapter Notes - Chapter 5: Intergenerational Equity, Overdraft, Hydraulic Head
Document Summary
Water scarcity has multiple aspects and diff definitions of scarcity try to capture one or more of these facets. Falkenmark introduced a water crowding indicator: number of people sharing a unit of water. Later converted from people per unit water to water availability per capita. As this indicator increased, there would be an increase in societal water stresses. Current: focuses on how much water is availbel to meet the needs of each prson. Weakeness: doesnot take into account differences in water needs among different countries or regions. Wta: withdrawal to availability, also called the criticality ratio. Ratio of annual water availability and uses the thresholds levels to define different levels of stress. Takes into accounts different water needs of different countries by using water withdrawals as the numerator. Draws our attentioan to when a country is using a large fraction of tis available water supply: at levels of 40% -- should expect systems such as ecosystem degradation etc.