WATER

ALAN SNITOW and DEBORAH KAUFMAN, filmmakers, July 14, 2004
CZIKOWSKY: We have the capability to turn salt water into drinking water. Are we getting close to the point where an international humanitarian effort needs to use this option? I know one objection to the loss of this water could affect the sea ecology, so I wonder, isn’t there a way the water could be recycled back into the ocean as salt water?
SNITOW and KAUFMAN: Desalination is being used in some parts of the world to convert salt water into drinking water but it is very expensive and consumers a lot of energy—which is why it works for the Saudis but is probably not going to be the solution for the rest of the world. In the U.S., much more effort needs to be placed in water conservation, in rethinking the wasteful uses of water in the agribusiness sector, and in limiting contamination of water by toxics.

WILLIAM CLINE, Center for Global Development Senior Fellow, November 19, 2007
CZIKOWSKY: What is global warming doing on our supply of water? Are warmer temperatures part of the explanation why water resources seem to be dwindling?
CLINE: There has been a relatively high incidence of drought in the United States and elsewhere in the past year. Like Katrina, it is ambiguous whether we should attribute this to the effects already being felt from global warming, but the answer is probably “yes to some extent”. Basically global warming intensifies evaporation and rainfall. The problem is that the increase in the rainfall tends to be more concentrate in areas other than the mid-continents. Meanwhile evaporation rises rapidly with temperature, and it is the difference between evaporation and rainfall that determines drying. In short, yes, I think the warming already is having some effect on water availability, but the impacts are likely to be much more severe with the kind of warming possible by late this century.