How is ozone formed in the upper atmosphere? State its importance. What is responsible for its depletion ? Write one harmful effect of ozone depletion.

Explanation

Ozone is formed in the upper atmosphere by the reaction of ultraviolet (UV) radiations on oxygen `(O_(2))` molecules.
Importance. The ozone layer acts as the ozone shield over the surface of the earth and absorbs the harmful ultraviolet radiations of the Sun and prevents them from reaching the earth's surface. The damaging effect of CFCs (Chlorofluorocarbons) is responsible for the depletion of ozone layer.
Harmful effects . The thining of ozone layer results in an incrase of UV-B radiation reaching the earth 's surface . This increase the incidence of cataract and skin cancer diminishing the immune system ' s function.