Ouch...the holy Ozone layer

Mike Agliolo/Science Photo Library

In February this year I left the bitterly cold British winter for the sunshine of Australia’s east coast. Having spent several days sightseeing in Melbourne and the Great Ocean Road my mates were keen to hit the beaches further north at Byron Bay and soak up some of the glorious sunshine. One morning the weather was disappointingly overcast and mild so we didn’t bother using sun cream, having used several tonnes the previous few days at the beach. Big mistake, by the afternoon we were all horrifically sunburnt and resembled (to much laughter of the locals) three "Mr Tomato Heads".

I had heard that Australia had significantly high incoming UV rays and the highest skin cancer incidence rate in the world, but I had never imagined that on such an overcast day we would be caught out like that.

Watching BBC news a few weeks ago the headline was broadcast that ozone depletion over the Arctic had hit a record level, creating a hole in stratospheric ozone that reached as far as Scandinavia and could even be compared to the ozone hole over Antarctica. I became worried, would the incidence of UV rays increase dramatically over the UK? Would I be confined to the shade during daylight hours, constantly at risk of sunburn and skin cancer?!

Ozone depletion is a glaring example of human impact upon nature, and the signing of the Montreal Protocol in 1987, which banned the production of many ozone depleting substances, demonstrates man’s role as “Stewards of the Earth System” as Will Steffen et al state in their 2007 review paper The Anthropocene: Are Humans Now Overwhelming the Great Forces of Nature?.

My starting point is to examine the causes of ozone depletion, first looking at the recent Arctic depletion event, the importance of Chlorofluorocarbons (CFCs) and Polar Stratospheric Clouds (PSCs), the chemical processes research from Paul Crutzen that was awarded the Noble Prize in 1995 and also study the interactions of tropospheric ozone which in high volumes causes photochemical smog. I will also compare the influence of ozone on the climate with other aerosols, both natural and man made.