Chlorofluorocarbons (CFCs): Extended Impact

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Despite these important steps, previously released CFCs continue to damage the ozone layer because they can remain in the atmosphere for more than 100 years. Ozone depletion is particularly bad over the Antarctic, seasonally producing an ozone hole, a large area of the atmosphere that contains extremely low amounts of ozone. Low levels of ozone have also been observed over the United States, Canada, Japan, Russia, and Europe. Scientists predict that the highest levels of CFCs in the atmosphere will occur during the first decade of the 21st century. If international agreements hold, the ozone layer is expected to recover around 2050.

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