The Ozone Layer Its Photochemical Formation and Degradation Processes

1 The Ozone Layer Its Photochemical Formation and Degradation Processes 

Ozone is formed by the photodissociation of molecular oxygen, 02, with UV light of very short wavelength (around 200 nm) 

Ozone itself absorbs light of longer wavelength, near 300 nm, and undergoes a dissociation reaction 

The O atoms then react with ozone to again form molecular oxygen, 02 

In this way an equilibrium is maintained between the three forms of oxygen, O, 02 and 03. This equilibrium can be upset by chemical species which are carried to the upper atmosphere, specifically nitrogen oxides and chloro-fluorocarbons. 

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