Geography
The Geopolitics of Transboundary Aquifer Management in Arid Regions
Quick fact
The world's largest transboundary aquifers, such as the Nubian Sandstone Aquifer System in North Africa, contain thousands of years' worth of water, yet no binding international treaty specifically governs them, leaving nearly 600 shared aquifers largely unregulated.
Why this is interesting
You can see a river, but you can't see the water beneath your feet—until it becomes a geopolitical battleground. How do nations divide an invisible resource?