This undated photo shows polar stratospheric clouds lit from below near Kiruna, in Sweden. Polar stratospheric clouds, long known to play an important role in Antarctic ozone destruction, are occurring with increasing frequency in the Arctic. As high altitude clouds that form only at very low temperatures, they act as 'breeding grounds' for ozone-destroying molecules. (HO/NASA/Lamont Poole GN/jp/Reuters)
If not WHY NOT??????