Question:What actually happens when UV radiation is stopped by the Ozone layer?
Ultraviolet light splits an ozone molecule into an oxygen molecule and an oxygen atom.
The energy of the UV photon is converted to heat through this process.
UV + O3 ⇒ O2 + O + heat
The Ozone is not permanently destroyed however because a single oxygen atom is extremely reactive and quickly reacts to reform a new ozone molecule.
O2 + O ⇒ O3