SEEN from space, the Earth is a water-world, its oceans more obvious than its land. But not all of the planet鈥檚 water is so easy to spot 鈥� 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 鈥淭he hunt for the world鈥檚 hidden water鈥�). In others, the news is grim: it seems Canada鈥檚 water reserves are less bountiful than expected. But either way, knowledge is power.
Advertisement
The work of the world鈥檚 water cartographers is not done, however. Drinkable water is widely used in mining, agriculture and manufacturing. These hitherto unconsidered demands on the supply of drinkable water remain largely unquantified.
So maps of the world鈥檚 hidden water are a good start. But to fend off future water wars, we鈥檒l need to find out where it goes, too. Or else thirsty neighbours will soon find new reasons to squabble.