What do you mean by ozone hole? What are its consequences?

The depletion of the protective ozone layer by ozone-depleting substances (ODS) such as nitric oxide and chlorofluorocarbon compounds (CFCs) to create a hole in the ozone layer is called ozone hole. Chlorine from chlorofluorocarbons (CFCs) is responsible for destroying a part of the ozone layer over Antarctica. Great loss of ozone has occurred since the early 1880s in the ozone layer over Antarctica producing a massive ozone hole which occurs mainly during spring time i.e. September-October and replenishes after spring i.e. November-December.
The depletion of ozone layer leading to ozone hole has mainly been observed in the stratosphere over Antarctica.
Consequences or harmful effects of depletion of ozone layer:
(i) Skin cancer: Due to depletion of ozone layer, the ultraviolet radiations coming from the sun can pass through the stratosphere and reach the surface of the earth. This type of radiation is known to be cancer causing agent.

(ii) Effect on the immune system: The ultraviolet radiations are also likely to suppress the immune system. The immunity against certain diseases is likely to decrease. This will lead to herpes and other diseases.

(iii) Loss of sight: The ultraviolet radiations damage the cornea and lens of the eye, thereby resulting in weakening of eyesight and may lead to blindness.