We all know that California is a desert, right? But we irrigate, and as a result we support rich farmland and big cities. What happens, however, if we take too much water, or if the amount of water coming into the Sierras falls (as global warming experts predict it will)? Well, the desert comes back, of course.

This article reports from a meeting of the American Geophysical Union this week in San Francisco. It states that the Sacramento and San Joaquin drainage basins have shed more than 30 cubic kilometers of water since late 2003. That’s a staggering amount of water, and the losses are likely to continue to grow as long as we take out more water than is coming in.

Interesting measurement technique too – they have satellites “weighing” the planet.