The main cause of ozone layer depletion is the release of human-made chemicals called chlorofluorocarbons (CFCs). These compounds, once widely used in refrigeration, air conditioning, aerosol sprays, and foam production, are very stable and can rise into the stratosphere. There, ultraviolet (UV) radiation breaks them down, releasing chlorine atoms. These chlorine atoms catalytically destroy ozone molecules, with one chlorine atom capable of destroying thousands of ozone molecules
. Other significant ozone-depleting substances include halons (used in fire extinguishers), carbon tetrachloride, methyl chloroform, hydrochlorofluorocarbons (HCFCs), methyl bromide (a pesticide), and nitrous oxides released from agricultural and industrial activities. While natural processes such as volcanic eruptions and solar variability contribute to ozone depletion, their impact is minor compared to these human-made chemicals
. Unregulated rocket launches have also been identified as a growing cause of ozone depletion, potentially causing more damage than CFCs if left uncontrolled
. In summary, the primary driver of ozone layer depletion is the emission of chlorofluorocarbons and related halogenated compounds, which release chlorine and bromine atoms in the stratosphere that break down ozone molecules and thin the protective ozone layer.
