The Last Drop

The current New Yorker has a great essay on the possibility (I'd say likelihood) of a global catastrophe:

“Philosophers and economists at least since Copernicus have noted that, although no substance is more valuable than water, none is more likely to be free. In “The Wealth of Nations,’’ Adam Smith called this the “diamond-water paradox”: although water is essential for life, and the value of diamonds is mostly aesthetic, the price of water has always been far lower than that of diamonds. Economists often argue that water should be considered a commodity, like housing or food. But water possesses an intangible, even mystical, quality that transcends the principles of economics; people simply don’t think about it in the way that they think about transportation or clothing—and they never have. Water is precious, but not like oil, which, once burned, is gone forever. While there is almost no human activity that doesn’t depend on water in some way, it never actually disappears: when water leaves one place, it simply goes somewhere else.

Water that dinosaurs drank is still consumed by humans, and the amount of freshwater on earth has not changed significantly for millions of years. But that doesn’t mean it’s available when or where it is needed. Nearly all of the earth’s water is in the ocean. Only three per cent is even theoretically available for humans to drink. Most of that is locked in polar ice caps and glaciers, or deeply embedded in layers of rock. If a large bucket were to represent all the seawater on the planet, and a coffee cup the amount of freshwater frozen in glaciers, only a teaspoon would remain for us to drink."