In the new paper, Dr. Qing-Bin Lu, a Professor and University Research Chair in Chemical Physics at the University of Waterloo in Canada, argues that the Antarctic ozone hole is not closing as fast as expected, indicating that another ozone-destroying mechanism may be at play. He points the finger at cosmic rays — “high-energy protons and atomic nuclei that move through space at nearly the speed of light” — interacting with halogen-containing gases in the stratosphere. The halogens include chlorine, fluorine, bromine, and iodine.
Looking at decades of atmospheric data and citing numerous prior studies, Lu also claims that ozone levels in the lower stratosphere about 14 to 21 kilometers above the tropics (depicted below) have fallen by around 40% to 70% since the 1960s, with the greatest decline at the equator, constituting an unrecognized ozone hole. Moreover, it’s far larger in area.Is There a Giant Ozone Hole Over the Tropics? – Big Think