Guest: Kate Allen, climate change reporter

Chlorofluorocarbons, a.ka. CFCs, are chemicals that were used in all kinds of household items in the 70s and 80s, but they were found to be causing a massive hole in the Earth's ozone layer. The world committed to act and their use was banned. The ozone layer is now healing, but new research shows that some CFC levels are mysteriously rising. What does that mean and what will the impact be on the environment?

This episode was produced by Brian Bradley, Paulo Marques and Raju Mudhar.