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Join us in our quest to raise $40 million in an effort to bring clean drinking water to millions of people around the world. Donate now at teamwater.org. In school, you probably learned about the water cycle with a diagram that looked a lot like this one. The problem is it's wrong. Or at the very least, it's pretty misleading. Hi, I'm Cameron and this is Minute Earth. So, let's check this diagram out. Look at all the space and the arrows dedicated to the stuff going on up here. Which seems to suggest that most of the fresh water on our planet cycles from clouds and lakes to rivers to ultimately back to the ocean. But the non- water in this loop at any given time only accounts for
about 2% of Earth's fresh water. Basically a rounding error. The majority of our fresh water, about 70% of it, is locked away in glaciers and ice caps. All that water is represented here by this teeny tiny part of the diagram. But that's not even my bone to pick here. It's down here where according to the picture, not that much is happening. But in reality, the second largest portion of our fresh water, almost all of what isn't locked up in ice is underground. You see, a small amount of surface water escapes the Cloud Lake River loop and makes its way underground. And it soaks into the permeable rock under our feet,
kind of like water in a sponge, moving downward until it hits a layer of less permeable rock. And over time, this water flows slowly toward the ocean, like really slowly. It might take a drop of water years to get there. And a little bit of the water in that first layer will take a different path. It can seep into a lower layer deeper and deeper into the Earth's crust. Any tiny trickle of water that ends up here might filter through the deep cracks and pores of rocks for the next 10,000 years, meandering toward the ocean. And even then, some of that deep water can seep even deeper into the Earth's crust. Some of these bodies of water, called aquafers, are so deep that they can get
dragged along with the Earth's tectonic plates or even partially dragged underneath the ocean floor. Or the water in them creeps so slowly through such dense rock that heat and pressure lock it into minerals until the tectonic plate carrying it is recycled through a volcano, which means that the crust rock is melted and the aquifer turns to steam. And wow, this is taking forever to animate. But in real life, this volcano bit happens millions of years in the future. And at least these days, there's also one more way for water to make it out of Earth's aquifers, one that doesn't appear on this diagram at all. Typically, us. We humans have become really good at pumping water out
of the ground for our own use. This is why making sure we understand this part of the diagram. You know, what actually happens down here and how long it takes is so important. Because although the underground supply of fresh water is huge, it's also fragile. And once an aquafer is drained, it can take decades or longer to replenish. And once an aquifer is contaminated, it may never be clean again. This video could not have been made without help from our great friend Dr. John Van Stan, professor in the department of biological, geological, and environmental sciences at Cleveland State University in Ohio.
He's got a book out written with his co-author Jack Simmons called Hydrarology and its discontents. It's part water science, part philosophy, and all nerding out about the paradoxes of dealing with and managing the single most important life-giving resource on our planet. Seriously, if you are looking for a deep and thoughtprovoking dive into our complicated, fraught, and fascinating relationship with water, this book is for you. In fact, we have a discount code just for our audience that will get you 20% off if you order through Springer Nature in the next month. As always, thanks, John.
