Hot countries: Environment > Water stats
Definitions
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Availability:
Water availability per capita (1961-1990 (avg.))
Units: Thousands Cubic Meters/Person
Units: This variable measures internal renewable water (average annual surface runoff and groundwater recharge generated from endogenous precipitation) -
Dissolved oxygen concentration:
Dissolved oxygen concentration
Units: Milligrams/Liter
Units: The country values represent averages of the station-level values for the three year time period 1994-96, exceptwhere data were only available for an earlier time period (1988-1993). The number of stations per country varies depending on country size; number of bodies of water; and level of participation in the GEMS monitoring system. The data from "The Wellbeing of Nations" included a smaller subset of stations representing outfalls of major watersheds. An analysis of a sample of countries with numerous stations found that the data for stations in the subset is broadly comparable to the data for all GEMS stations in those countries. -
Freshwater pollution:
Industrial organic pollutants per available freshwater
Units: Metric Tons of BOD Emissions per Cubic Km of Water
Units: Emissions of organic water pollutants are measured by biochemical oxygen demand, which refers to the amount of oxygen that bacteria in water will consume in breaking down waste. This is a standard water-treatment test for the presence of organic pollutants. The data from the World Bank, which represented BOD emissions (kilograms per day) were normalized by the combination of water availability per capita and water inflow availability per capita from the WaterGap2.1 model. In calculating the ESI, the base-10 logarithm of this variable was used. -
Phosphorus concentration:
Phosphorus concentration
Units: Milligrams/Liter
Units: The country values represent averages of the station-level values for the three year time period 1994-96, except where data were only available for an earlier time period (1988-1993). The number of stations per country varies depending on country size; number of bodies of water; and level of participation in the GEMS monitoring system. The data from "The Wellbeing of Nations" included a smaller subset of stations representing outfalls of major watersheds. An analysis of a sample of countries with numerous stations found that the data for stations in the subset is broadly comparable to the data for all GEMS stations in those countries. -
Salinisation:
Electrical conductivity
Units: Micro-Siemens/Centimeter
Units: The country values represent averages of the station-level values for the three year time period 1994-96, except where data were only available for an earlier time period (1988-1993). The number of stations per country varies depending on country size; number of water bodies; and level of participation in the GEMS monitoring system. -
Severe water stress:
Percent of country's territory under severe water stress
Units: Percent of Land Area
Units: This data is derived from the WaterGap 2.1 gridded hydrological model developed by the Center for Environmental Systems Research, University of Kassel, Germany. The modellers derived, for each country, grid cell by grid cell estimates of whether the water consumption exceeds 40 percent of the water available in that particular grid cell. These were then converted to land area equivalents in order to calculate the percentage of the territory under severe water stress. -
Suspended solids:
Suspended solids
Units: Natural Log of Milligrams/Liter
Units: The country values represent averages of the station-level values for the three year time period 1994-96, exceptwhere data were only available for an earlier time period (1988-1993). The number of stations per country varies depending on country size; number of bodies of water; and level of participation in the GEMS monitoring system. Data from "The Wellbeing of Nations" included a smaller subset of stations representing outfalls of majorwatersheds. An analysis of a sample of countries with numerous stations found that the data for stations in the subset is broadly comparable to the data for all GEMS stations in those countries. The data in this table was transformed using the natural logarithm.
