SEEN from space, the Earth is a water-world, its oceans more obvious than its land. But not all of the planet’s water is so easy to spot – particularly the fresh water on which our civilisation depends.
Much of this water is hidden deep underground. Uncertainty about where it lies can cause neighbours to fall out. To track it, geographers are turning to the kind of high-tech tools that used to be the preserve of deep-pocketed oil and gas companies.
In some cases, as in the Nubian aquifer below North Africa, the results are happy, deflecting a looming water war (see…
