There is no doubt that global warming is going to change the pattern of water availability throughout the World. Some areas will get more rainfall, in some instances significantly higher amounts, or the same as before but as fewer and more intense rainfall events. In contrast, other areas will get less rainfall leading to severe and possibly permanent drought, a scenario currently playing out in Australia and some parts of central Africa. It remains difficult to be precise at this stage how it will affect specific areas and there will be local variations arising from more regional trends. Global warming will also lead to increased evaporation and plant evapo-transpiration creating more water movement between the land and the atmosphere as well as melting snow and glaciers releasing more freshwater.
|Figure 1. The Hubbert Curve|
|Figure 3. Peak water in the USA compared to economic growth|
|Figure 4. Water supply sustainability index predicted for 20050.|