yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Climate 101: Ozone Depletion | National Geographic


2m read
·Nov 11, 2024

(upbeat piano music)

[Narrator] 15 to 35 kilometers above Earth's surface, a gas called ozone surrounds the planet. The ozone layer acts as a barrier between Earth and ultraviolet radiation from the Sun. However, pollution has caused the ozone layer to thin, exposing life on Earth to dangerous radiation.

(upbeat piano music)

Earth's atmosphere is made up of six layers. The second layer, called the stratosphere, contains the ozone layer. The ozone layer is made up of a highly reactive molecule called ozone, which contains three oxygen atoms. Ozone is a trace gas in the atmosphere. There are only about three molecules for every 10 million molecules of air, but it does a very important job. The ozone layer acts as Earth's sunscreen, absorbing about 98% of damaging ultraviolet or UV light.

But the ozone layer has gotten thinner. Chemicals called chlorofluorocarbons or CFCs are the primary culprits in ozone layer breakdown. A CFC is a molecule that contains the elements carbon, chlorine, and fluorine. CFCs are mostly found in refrigerants, aerosols, and plastic products. When CFCs are exposed to ultraviolet rays in the atmosphere, they break down into substances that include chlorine. The chlorine reacts with the oxygen atoms in ozone and rips apart the ozone molecule.

Areas of damage in the ozone layer are often called ozone holes, but that name is misleading. Ozone layer damage is more like a thin patch, with the thinnest areas near the poles. The ozone layer above the Antarctic, in particular, has been impacted by pollution since the mid-1980s. There, the region's low temperatures speed up the conversion of CFCs to ozone-damaging chlorine. About 90% of CFCs currently in the atmosphere were emitted by industrialized countries in the northern hemisphere.

In 1989, the Montreal Protocol banned the production of ozone-depleting substances. Since then, the amount of chlorine and other ozone-depleting elements in the atmosphere have been falling. Scientists estimate that chlorine levels will return to their natural state in about 50 years. By then, the Antarctic ozone hole will shrink to smaller than eight million square miles.

(slow piano music)

(upbeat synthetic pop music)

More Articles

View All
Office Hours at Startup School 2013 with Paul Graham and Sam Altman
We have to sit up straight. We have lower, since this is not right. Admiral Rickover would not stand for this. Um, okay. Uh, George, Nick, what are you working on? So we are building a multiplayer programming game for teaching people how to code. So lik…
Monopsony employers and minimum wages
In this video, we’re going to review what we’ve already learned about monopsony employers that we’ve covered in a previous video. But then we’re going to add a twist of adding a minimum wage and see what happens. And it’s actually interesting; it’s actual…
How to Win an Interstellar War
Could aliens destroy us from light years away? Mh, another day at the Kurzgesagt Labs, where we answer the most important questions with science. Today: how might civilizations wage war across light years? What kind of devastating weapons could they use, …
Khan for Educators: Khan Academy’s learning experience
So, at Khan Academy, we are striving to create personalized mastery-based learning that transforms students’ mindsets. Within that, I think there are three things that make our value proposition unique. The first is that our content is provided free of c…
Robot Butterflies FOR THE FUTURE - DEEP DIVE 3 - Smarter Every Day 106
Hey, it’s me Destin, welcome back to Smarter Every Day. So before we start the butterfly deep dive, the one question I get more than anything else here on Smarter Every Day is, what’s your educational background? So, I figured I’d tell you. I got my Bache…
Saving wisely: Emergency funds | Budgeting & saving | Financial Literacy | Khan Academy
In life, there are things that we expect, and there’s other things that we don’t expect. When we think about it from a finance point of view, the things that we might expect is, okay, we’re going to get a regular paycheck because of our work, and we’re go…