3.5 Ozone depletion
Ozone is a gas . There is a layer of ozone high up in the atmosphere. The Ozone layer is about 25 kilometres above the ground.
Keywords:
Radiation - Known as UV - Full form of UV is Ultra Violet rays entering from the Sun.
. Too much UV rays can cause skin cancer.
. Can even harm the single cell organisms like plants and aquatic animals.
. Between the Earth and Sun, there is an invisible pale blue protective shield called Ozone layer.
Keyword:
Atmosphere
Oxygen molecules contain 2 atoms.
. Ozone layer is about 3-5 millimetres in thickness. Short form of millimetres - mm
. It protects us from UV rays
. There was a hole in the Ozone layer.
. In 1970 scientists discovered that certain man made chemicals were responsible for the hole.
Keywords:
Chlorofluorocarbon - Short form - CFCs
Nitrogen
Nitrogen - Coming out from a wide range of industrial and consumer appliances.
Examples :
. Refrigerator
. Air Conditioner
. Fire Extinguisher
Blowed towards the ozone layer





