How does the long lifespan of CFC molecules affect the rate

Subject : Physics

Question: How does the long lifespan of CFC molecules affect the rate of repair of the ozone layer?

Expert Verified Solution:

The long lifespan of chlorofluorocarbon (CFC) molecules significantly slows the rate of repair of the ozone layer. CFCs are stable compounds that do not break down easily in the lower atmosphere, allowing them to gradually rise to the stratosphere over many years. Once in the stratosphere, CFCs are broken down by ultraviolet (UV) radiation, releasing chlorine atoms. These chlorine atoms then participate in catalytic reactions that destroy ozone molecules. Because CFCs have a long atmospheric lifetime—often lasting up to 100 years—they continue to release chlorine over extended periods, persistently depleting the ozone layer.

As a result, even though the production of CFCs has been largely banned or reduced under international agreements like the Montreal Protocol, the existing CFCs already in the atmosphere will continue to affect the ozone layer for many decades. This ongoing presence of CFCs and their breakdown products means that the recovery of the ozone layer is a slow process, taking potentially several decades to centuries to fully restore to pre-CFC levels.