ABSTRACT
The problem The illusion of plenty created by the pouring of water from faucets at all times of day or night is first undermined in the minds of the faucet turners when they learn that only 3 percent of the water on the planet is fresh (Table I.1). Shock may set in at the news that most of that fresh water is inaccessible to us, as it is trapped in ice and snow or deep in layers of sedimentary rock. In fact, we rely on a mere quarter of a percent of the earth’s water supply for fresh water, and we have managed to pollute much of this global treasure (De Villiers 2000). One out of six people in the world lacks access to water; in Asia, Africa, Latin America and the Caribbean, 20-50 percent of people lacked adequate access in 2000 (Satterthwaite and McGranahan 2007). Even in the prosperous US, 30-40 percent of all lakes, rivers, and estuaries do not meet current water quality standards (Table I.2). Global warming will only exacerbate our water problems. The disappearance of ice and snow deprives us of valuable water services. Their light color reflects heat back into the atmosphere, moderating the evaporation of our fresh water. Snow melt is more efficient than rain at replenishing the water supply of underground aquifers. The slow trickle of melting snow provides a steady drip into the aquifers, while rain can hit the ground so fast that it skids over the surface, sending water to open streams and bodies of water, where it evaporates into the ever warming air.
