Global Climate Change
The changes in the global patterns of rainfall and temperature, sea level, habitats and the incidence of drought, floods and storms resulting from changes in the earth's atmosphere, believed to be mainly caused by the enhanced greenhouse effect.
The Greenhouse Effect
The process by which certain gases (water vapour, carbon dioxide, methane and chloroflurocarbons (CFCs)) allow short-wave radiation from the sun to pass through the atmosphere and heat up the earth, but trap an increasing proportion of long-wave radiation from the earth. This radiation leaves to a warming of the atmosphere.
The Enhanced Greenhouse Effect
The increasing amount of greenhouse gases in the atmosphere as a result of human activities, and their impact on atmospheric systems, including global warming.
A sever reduction in the quality of soils, often through soil erosion, salinzation or soil exhaustion (loss of soil fertility).
Physical Water Scarcity
Lack of availability water where water resource development is approaching or has exceeded unsustainable levels; it relates availability to demand and implies that arid areas are not necessarily water scarce.