20th Anniversary of ozone hole discovery – International Ozone Day

Friday (16 September) is International Day for the Preservation of the Ozone Layer. This year scientists at British Antarctic Survey (BAS) commemorate their discovery of the Antarctic ‘ozone hole’ 20 years ago and commend the historic international agreement (the Montreal Protocol 1987) that will lead to its eventual recovery.

Jonathan Shanklin, one of the researchers who made the discovery says, “The 2005 hole is larger and deeper than the holes that formed when the discovery was made but the situation would be much worse if the Montreal Protocol had not come into force. This agreement shows us that global action by governments to stop the release of ozone depleting chemicals really can help society to successfully mitigate a global environmental problem. We are still experiencing large losses of Antarctic ozone each spring because CFCs and other chemicals live for a long time in our atmosphere. However, the ban ensures that we will see an improvement in the future. We now need to take similar actions to control greenhouse gasses, otherwise we will bequeath future generations a significantly different climate from that of today.”

Covering an area of around 22 million square kilometres this year’s hole is a little smaller than the record-breaking event in August 2003. Measurements made during August and September at BAS Halley and Rothera Research Stations reveal a 50% reduction on normal ozone levels over the base of the Antarctic Peninsula and the Weddell Sea, and a 20% reduction over the tip of South America and the Falkland Islands. The increased ultra violet light reaching the surface poses a medical hazard to people living under the ‘hole’ and without suitable protection people face the prospect of rapid sunburn and potentially more serious skin damage.