Aquifer
A rock, such a chalk, which will hold water and let it through
Arid and semi-arid
Describe where rainfall is less than 250mm and 500mm of precipitation per year respectively
Desalination
The conversion of salt water into fresh water
Drought
An extended period of abnormally dry weather that causes water shortages and crop damage. A drought starts when total rainfall is well below average for several months
El Nino
A southerly warm ocean current, which develops off the coast of Ecuador, it is associated with major variations in typical climates
Groundwater
All water found under the surface of the ground which is not chemically combined with any minerals present, but not including underground streams
High pressure
A region of high atmospheric pressure, otherwise known as an anticyclone
Infiltration
The process of the water entering rocks or soil
Irrigation
The supply of water to the land by means of channels, streams and sprinklers in order to permit the growth of crops
La Nina
An extensive cooling of the central and eastern Pacific. Globally La Nina means that parts of the world that normally experience dry weather will be drier and those with wet weather will be wetter
Percolation
The filtering of water downwards through soil and through bedding planes, joints and pores of a permeable rock
Potential Evapotranspiration
The amount of evaporation and transportation that can occur given a sufficient supply of water
Precipitation
The deposition of moisture from the atmosphere onto the Earth's surface in form of rain, hail, snow, frost or sleet
Prevailing
Most frequent, most common
Privatisation
The sale of a business/industry so that it is no longer owned by the government
Rain shadow
An area of relatively low rainfall to the lee side of uplands (sheltered from winds). The incoming air has been forced to rise over the highlands causing precipitation on the windward side
Relief Rainfall
This forms when moisture-laden air masses are forced to rise over ground. The air is cooled, the water vapour condenses, and precipitation occurs
Riparian
Relating to a river bank. Owners of land crossed or bounded by a river have 'riparian' rights to use the river
Spatial imbalance
The uneven distribution/location across a landscape or surface e.g. population
Stream flow
The flow of water in streams, rivers and other channels
Surface runoff
The movement of over ground of rainwater. It occurs when the rainfall is very heavy and when the rocks and soil can absorb no more
Urbanisation
The migration of rural populations into towns and cities
Virtual water
The amount of water used in the production of a good or service
Water rights
The legal right of a user to use water from a water source e.g. a river
Water Scarcity
Can be divided into 'apparent scarcity' which exists when there is plenty of water buy it is used wastefully.
And 'real scarcity' which is caused by insufficient rainfall or too many people relying on a limited resource
Water Stress
Measured as annual water supplies below 1,700m3 per person
Water wars
International conflict as a result of pressure on water supplies
World Water Gap
The difference between those people, who live in water poverty and those who have ready and reliable access to water for drinking and sanitation