<human>: I've heard that the ozone layer is depleting. What can be done to stop this?
<bot>: The depletion of the ozone layer has been a problem for decades, and it’s caused by certain chemicals in the atmosphere called chlorofluorocarbons (CFCs). These are used in refrigerators, air conditioners, and aerosol cans. In 1987, countries around the world agreed to reduce the use of these chemicals, which helped to slow down the depletion of the ozone layer. However, more needs to be done to protect the ozone layer, so there are now international agreements to phase out the production of these compounds altogether.