Burleigh McCoy

And that groundwater is responsible for about half of the water people use globally.

Wow.

Thank you, aquifers, for keeping us all alive.

Seriously.

And for this episode, I called up someone who has a very close relationship with his local aquifer.

This is Hayes Kelman.

He's a fifth-generation farmer in western Kansas, and he loves it, getting his hands in the soil, watching a crop grow from seed to harvest.

But around the time he was in high school, he noticed something about the water they used to irrigate the family farm.

So his farm sits above the Ogallala or High Plains Aquifer, which is a huge aquifer.

It spans eight states and it's losing water like a lot of other aquifers around the world.

Sometimes it's because of cities, but a lot of the time it's because of farms using a lot of water.

Yeah, he says they're growing the same crops, but it's kind of up to chance what he'll harvest based on how much or how little rain they get.

It's true, and it's getting worse for Hayes and a lot of other farmers all over the world.

But understanding the issue on a global scale, that is a beast of a project.

And it's one that scientists hadn't tackled until a couple of years ago.

So definitely hundreds, maybe thousands.

It turns out that's a tough number for scientists to estimate because aquifers are underground.

Yeah.

So if that's the case, how do scientists get a sense of the state of the world's aquifers?

Yeah.