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Chemistry

The Chemical Dynamics of Ozone Depletion in the Stratosphere

Quick fact

A single chlorine atom released from a CFC molecule can destroy up to 100,000 ozone molecules before it is removed from the stratosphere, making even small releases of CFCs devastating to the ozone layer.

Why this is interesting

You might think of ozone as just a pollutant near the ground, but high above us, a protective layer of this molecule shields all life from the Sun's most energetic rays. Yet, this layer is under threat from a class of chemicals that were once considered perfectly harmless—how can that be?