You're probably thinking the same thing I was when I first heard of a global sand shortage: "I've seen massive deserts. How are we possibly running out of sand?"
It's not a stretch to say that sand is the foundation of our cities. It's a key ingredient in the concrete we use to construct highways and buildings. We use it to make glass. It's even in the chips that power our phones and computers. We use 50 billion tons of sand every year. And it turns out that not all sand is created equal.
"There is of course a lot of sand in deserts, the problem is it's basically useless to us." says Vince Beiser, author of The World in a Grain: The Story of Sand and How it Transformed Civilization. Useless because desert sand has been eroded by wind over millions of years, making the grains smooth and round. That's not ideal for making concrete and other resources.
The sand we want is rougher, with corners and angles, so the grains can lock together. "It's like the difference between trying to build something out of a stack of marbles, as opposed to a stack of tiny bricks." Beiser says. That sand comes from places like riverbeds and beaches.
As with shortages of other natural resources, the dearth of sand involves a finite supply of the material and a growing number of people fleeing rural areas for cities. According to Beiser, the world adds the equivalent of eight New York Cities every year. Given that the construction of a single building can require about 3,000 tons of sand, it's not surprising that this resource is slipping away.
So now what? Researchers are looking into a variety of replacements for sand as an ingredient in concrete. Shredded plastic, shredded rubber and even hemp are being used on a limited scale. But Beiser says the shortage is a symptom of a bigger problem. "We've got to find ways to build our cities that not only use less sand, but they use less of everything across the board. We've just got to find ways to live our lives more sustainably."
Beiser spoke with CNET for our Now What series. Watch the complete interview in the video above.