Ozone formation occurs naturally in the Earth’s atmosphere through a process involving ultraviolet (UV) radiation from the sun. UV radiation splits oxygen molecules (O2) into individual oxygen atoms (O). These oxygen atoms then combine with other oxygen molecules to form ozone (O3).
The formation of ozone takes place as shown below:
Ozone depletion refers to the destruction of the ozone layer in the stratosphere due to human-made chemicals, such as chlorofluorocarbons (CFCs). Such as Chlorofluoro carbons (CF2Cl2)⁽¹⁾ called freons, absorb the ultraviolet radiations and get photolyzed to liberate free chlorine atoms. The free chlorine atoms catalyze the decomposition of ozone resulting in the depletion of the ozone layer.
⁽¹⁾ One molecule of CF2Cl2 can destroy more than one thousand O3 molecules in the stratosphere.
Thinning of the ozone layer allows more harmful UV radiation to reach the Earth’s surface, increasing the risk of skin cancer and cataracts in humans.
Higher UV levels can harm marine ecosystems, affecting phytoplankton, fish larvae, and other aquatic organisms.
Increased UV radiation can reduce crop yields and disrupt ecosystems, impacting food chains.
