From the Middle East to the Caribbean to Australia, people around the world are dealing with water scarcity.

It’s easy to look at a portrait of Earth and think of our home as a water planet. After all, 75 percent of the surface is covered with water. But the thin skin of liquid that surrounds our rocky home is misleading—if you took all the water on the planet and bunched it into a ball, that ball would be less than half the diameter of the Moon. That’s not a huge amount of water.

Plus, the proportion of water that humans can use for daily use is actually pretty small. Most of the world’s water is saltwater in the oceans. Only about three percent of the water is fresh. Half of that is locked in glaciers, the polar ice caps and snow. Read more

Some people like to stick to the sand when they go to the beach. The ocean can harbor sewage-related fecal contamination and a random infectious bacteria infestation or two. But it turns out that those who stay beach-side are actually making the more disgusting choice. New research shows that sand can be even more contaminated than ocean water.

Chemists from the University of Hawaii recently learned that levels of fecal bacteria in beach sand can be up to 100 times higher than in the water nearby. And, being scientists, they immediately set out to discover why. Their task was more daunting than they initially thought: a majority of studies on marine beach bacteria have taken place in water, not sand.

So the scientists went back to the lab. There, they spiked beach sand and sea water with raw municipal wastewater and the team was able to study how contaminated coastal waters impact beaches themselves. Their research revealed that, unsurprisingly, water and sand behave in completely different ways: waterborne bacteria dies off and disappears relatively quickly, but when microbes get trapped in sand they take much longer to decay. Because microbes can hang around for so much longer in the sand, they could create long-term public health problems on beaches long after water cleanups have occurred. Read more

It’s no secret that Earth is a wet and wild place—from grade school onward, most people can readily cite the fact that water covers about 70 percent of the planet’s surface. And images taken from space show our home world as a “blue marble” awash in oceans, rivers and lakes.

But life on Earth depends on a lot of water that we can’t see, from vapor in the air we breathe to freshwater in deep aquifers used to irrigate crops. Figuring out where this water came from, where it is now, how it moves around and how humans are affecting its flow will be critical to management of this most precious resource.

This week, Generation Anthropocene goes on a continent-hopping tour of the invisible water that drives planetary processes. Producer Mike Osborne kicks things off by chatting with Jenny Suckale, a Stanford geophysicist who has been tracking melting in Antarctica and how it may contribute to global sea level rise. Suckale and her colleagues have been especially focused on ice streams and how they move meltwater from the interior of the ice sheet into the ocean. Read more

Set against the velvet blackness of outer space, our home planet looks like a “blue marble”—bright, shimmering, and mostly fluid. Indeed, it is the abundance of water on its surface that gives Earth its blue appearance. Water covers approximately 70 percent of our world’s surface. So it would seem that finding water is a trivial task. Yet only 2.5 percent of the Earth’s water is fresh and thus suitable for consumption.

Not only that, but of that 2.5 percent, more than two-thirds is locked away in glaciers and not particularly able to help meet the growing demands of society. By far, the most abundant and available source of fresh water is underground water supplies or wellsprings known as aquifers. Therefore, scientists and natural resource managers are very interested in tracking how these underground reservoirs of fresh water are changing with time. Read more