I’ve had a simple puzzlement concerning the ozone layer. Succinctly, the troposphere is largely and preferably ozone free. When it thermally rises at the tropics to become the stratosphere molecular oxygen cleaves under actinic radiation to from nascent oxygen that, in turn joins with molecular oxygen to form ozone. The stratospheric ozone, of course, is vital to protect against harmful radiation. Then at the polar vortices the flow once again returns to the troposphere. Ozone is undesirable in the troposphere and is removed at this point.
If this is accurate (?), why would halides that disassociate ozone (in conjunction with ice crystals only present at the Antarctic pole) be seen as adverse?