How CFCs Destroy Ozone Layer
When the CFC refrigerants are leaked from refrigeration or air-conditioning systems, they drift around the lower layers of the atmosphere. Slowly they start infiltrating into the upper layers of the atmosphere and soon reach the ozone rich stratosphere, where they undergo major chemical changes.
What Ozone Does:
In the ozone layer sunlight enters in its pristine pure form; it is called ultraviolet radiation, which is highly intense and dangerous to plant and human life. The ozone layer filters this highly intense sunlight and allows less intense sunlight, which is not harmful to human and plant life, to the surface of the earth.
How it Changes CFCs
The unfiltered sunlight bombards the molecules of CFC refrigerants, and they are pushed towards the stratospheric clouds over the poles. Due to this the CFC molecules get disintegrated. The chlorine atom removed from CFCs reacts with ozone molecule (O3) and converts it into oxygen molecule (O2).
Ozone is Transformed to Oxygen
Now, the oxygen does not have the capacity to filter the highly intense ultraviolet radiations. So what is happening because of the CFC refrigerants is that the protective ozone layer is getting converted into incapable oxygen. Due to this the amounts of ultraviolet rays reaching the surface of the earth becomes very high and then causes excessive heating in the environment, called the greenhouse effect.
The Greenhouse Effect
Due to the greenhouse effect the ice in Antarctica and the poles starts getting melted, which causes large amounts of waters drifting to the rivers, causing floods. Thus, due to depletion of the ozone layer, not only the temperature increases, but also the level of water that causes floods.
To prevent the depletion of the ozone layer due to CFC refrigerants, an international agreement called Montreal Protocol was signed by various countries in 1987. As per the agreement the use of the most dangerous group of CFCs comprising of R-11, R-12, R-113, R-114, R-115, R-500 and R-502, were scheduled to be phased out of production totally by January 1, 1996 in developed countries and by the year 2000 in developing countries.