The sun's rays break the bond of Oxygen OO
oxygen does not like being alone
loose Os who can't find a mate, will engage in a threesome. O-O-O a threesome of oxygen is called "Ozone" inb4 tranny jokes Oxygen are celibate they don't reproduce, and have no gender.

As long as the sun is shining, the "ozone layer" is automatically sustained. Oxygen in the atmosphere turns into ozone automatically. If the sun puts out extra UV, more and more Oxygen gangbang into ozone to protect life on Earth from that UV. When the crisis is over, they convert back to normal oxygen.