Explain Ozone layer in short.

Ozone layer, comprising high concentration of ozone about 18-50 km above in the atmosphere, is commonly called ozone blanket. It is being depleted by air pollutants. Chlorofluorocarbons (CFCs) are synthetic harmful chemicals which are widely used in refrigerators and air conditioners as propellants. These chlorofluorocarbons are air pollutants and are mainly responsible for the depletion ofozone layer in the atmosphere. When these are released in the air, these harmful chemicals produce active chlorine' (Cl and CIO radicals) and fluroine in the presence of UV radiation. These radicals, through chain reaction, then destroy the ozone by converting it into oxygen. Due to this, the ozone layer in the upper atmosphere (i.e, stratosphere) becomes thinner. A single chlorine atom can destroy one lakh ozone molecules. Cholorofluorocarbons are, therefore, termed major ozone depleting substances (ODS). Other ozone depleting substances are nitrogen oxides and hydrocarbons. The thinning of ozone layer allows more ultra violet (UV) radiations to pass through it which then strike the earth. These cause following harmful effects on man, animals and plants:
(i) Skin cancer.
(ii) Damage to eyes, also increase incidence of cataract disease in eyes.
(iii) Damage to immune system.
(iv) Increased embryonic mortality in animals and humans.
(v) In plants too, there will be increased death rate of seedlings, increased incidence of harmful mutations and reduction in yields.

The ozone layer is a region in the earth’s stratosphere that contains high concentrations of ozone and protects the earth from the harmful ultraviolet radiations of the sun.

The ozone layer is found in the lower portion of the earth’s atmosphere. It has the potential to absorb around 97-99% of the harmful ultraviolet radiations coming from the sun that can damage life on earth. If the ozone layer was absent, millions of people would develop skin diseases and may have weakened immune systems.