Here’s a fascinating but frightening fact: in the last couple of decades, we humans have pumped so much water out of the ground that we have actually shifted the planet’s poles by almost a metre. Earth’s poles are not fixed points. They wobble around to the rhythm of several cycles, some millennia long, so it’s hard to tell what, if any, effect this human interference will have. But it does show us what an enormous amount of ground water we are using and how damaging the consequences could be.

Header image: Irrigation in the desert by GRID-Arendal (CC BY-NC-SA 2.0) flickr.com