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Hey, shortwaivers, Emily Kwong here with a love letter to the layer of the Earth's atmosphere that acts like a sunscreen.

I'm talking, of course, about ozone.

Without ozone, that would be impossible to live on Earth.

This is atmospheric scientist Irina Petro Padlovskik. The ozone is a layer of the

stratosphere with a high concentration of ozone molecules, each one made out of three oxygen atoms.

And it's very good for us. It protects us from the harmful muvee radiation. And that's why we want

more of this, not less of that.

To form, ozone needs sunlight, which bursts oxygen apart.

You know, the O2 version we breathe.

And then each single atom of oxygen can then connect with another O2 to form our girl, O3, aka Ozone.

But sunlight can also destroy ozone, and the balance generally depends on the season.

But starting in the 1970s, something weird happened.

Scientists noticed that ozone is changing slowly but surely.

But they didn't know how much it's changing until maybe the beginning of 80s,

when the scientists actually measured significant change

that was happening in springtime, in Antarctica.

And so they noticed that there was less ozone.

A giant hole is forming in the Earth's protective ozone layer. A scientist discovered a hole in this protective ozone. A giant hole is forming in the Earth's protective ozone layer.

Scientists discovered a hole in this protective ozone. A lot of people call it the

ozone hole, but it was really more of a thinning. Scientists launched weather balloons to study its

size, and they found something shocking. High levels of two chemicals, chlorine and

...