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How does ultraviolet radiation cause CFCs to release chlorine atoms?
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Ozone depletion
The Antarctic ozone hole reaches its maximum extent in October of each year. On October 7, 2021, when this image was captured, the Antarctic ozone hole spanned 24.8 million square km (9.6 million square miles).
When chlorofluorocarbons (CFCs) reach the stratosphere, they are exposed to high-energy ultraviolet radiation from the Sun. This radiation causes the CFC molecules to undergo a process called dissociation, in which the chemical bonds holding the molecule together are broken.12
This breakdown releases highly reactive chlorine atoms and free radicals. Once liberated, these chlorine atoms act as catalysts that strip oxygen atoms from ozone molecules, effectively destroying them and contributing to the depletion of the ozone layer.12