Science not settled on Ozone

Letter sent to Sydney Morming Herald this morning...unlikely to see print...

Dear Editor,
Recent studies (DOI:10.1103/PhysRevLett.102.118501) indicate that Galactic Cosmic Rays (GCR) have played a previously unrecognised role in contributing to the formation of the Ozone Hole, something overlooked in Ben Cubby's opinion piece (We saved the Ozone Hole, now its time to save the climate, 27/3). Natural variation in GCR intensity linked to the solar cycle helps explain why the ozone layer has been so slow to recover since CFC's were banned in the 1980s. It also explains why we can expect the hole to actually increase in size this year as we enter one of the deepest solar minimums of the modern era. The story of the ozone layer is not that simple and clearly is not over just yet. The effect of GCR's on the rest of earth's atmosphere and climate remains the subject of continued research with initial findings pointing to a link between GCR intensity and global temperature. The lesson to be learnt is that, despite the claims of a few figures of authority, the science is not settled. Rather than turning the lights off for Earth Hour this year and working in the dark it seems some scientists and perhaps some reporters could benefit from working with the lights on for a change.