Ozone layer: It's healing, so are we..

Ozone layer is a vital region of Earth's stratosphere which is responsible for absorbing majority of UV rays radiated from the Sun. Those UV rays lies within a wavelength of 100 nm to 315 nm (An approx figure) is absorbed by Ozone layer. Ultraviolet B has the wavelength range between  280-315 nm and Ultraviolet C ranged between 100-280. Beyond 315 nm wavelength the UV rays known as Ultraviolet A and it can't be absorbed by ozone layer. Excess of UVA and UVC rays can cause skin cancer..

Ozone molecule basically consist of three atoms of oxygen bonded together. The mechanism for the production of Ozone layer was discovered in 1930 by Sydney chapman. Ozone in stratospheric region produced when the UV rays strikes an ordinary oxygen molecule and splits it into two atomic oxygen. These atomic oxygen is unstable in nature and thus bonded with another O2 molecule thus become an ozone molecule, O3.

Now the question is if Ozone is forming at a very high rate than how it is balanced with the destruction of the same. The answer is UV rays. The production of ozone takes place when UV rays of around 240 nm strikes the Oxygen molecule but when the UV rays of around 320 nm strikes the ozone molecule, it splits it again in one oxygen molecule that is O2 and one free atomic oxygen. Now that free atomic oxygen either combines with another oxygen molecule to create an ozone molecule or with another atomic oxygen to produce O2 molecule.. This continuous process of production and destruction is known as Ozone-Oxygen cycle.

 

Apart from this natural phenomenon, man made chemicals are also responsible for its destruction and excess of chemicals like Chlorofluorocarbons (CFCs), Bromofluorocarbons etc.. These compounds are very stable in nature and rise upto the stratospheric region where being bobarded with UV rays Cl and Br radicals gets liberated. The free radicals has the ability to initiate and catalyze a chain reaction which can destroy almost 100,000 of ozone molecules..

The first news regarding the depletion of ozone layer came into light in early 1970s. In 1978 USA, Canada and Norway banned the usage of CFC containing aerosols spray. The first sighting of excessive thinning of ozone layer was first announced on May 16 1985 in a paper appeared in nature by Joe Farman, Brian GArdiner and Johnathan Shanklin. 

In september 2000, the size of the ozone hole, as recorded by a satellite, in Antarctica reached greater than the size of North America i.e. 29.9 million Sq kilometer (Sounds scary!!!). But the good thing is the natural rate of production of Ozone is higher than its destruction (Yayyy..) Till now 197 countries signed a treaty to ban the use of CFCs (Montreal protocol). Though, some developed countries like USA can use only recycled and stockpiled CFCs.

The very recent observed results shows that the ozone hole over ANtarctica region has reduced to a great extent, now its only upto the size of India (Still a long way to go!!). Ozone layer is recovering now (Thanks to all who, directly or indirectly, causes recovery to happen) and it is predicted that if the recoverable rate remains intact, by 2050 it will be recovered fully.

Thanks to all for reading and as we all are the most beautiful creature of this home called Earth, We
request you to please avoid the use of chemicals which are responsible for the pollution as far as possible..