Here's why:
* CFCs are very stable in the lower atmosphere. This means they can persist for a long time and travel up to the stratosphere.
* In the stratosphere, UV radiation breaks down CFCs, releasing chlorine atoms.
* Chlorine atoms act as catalysts in a chain reaction that destroys ozone molecules. One chlorine atom can destroy thousands of ozone molecules before it is removed from the atmosphere.
This process, known as ozone depletion, leads to a thinner ozone layer, which allows more harmful UV radiation to reach the Earth's surface.
It's important to note: While fluorine is also present in CFCs, it doesn't play a direct role in ozone depletion. The primary culprit is chlorine.
