Arctic ozone hole moving south

By Louise Murray - 06 Apr 2011 8:37:0 GMT
Arctic ozone hole moving south

Unusual atmospheric conditions during the last Arctic winter have opened a massive hole in the ozone layer and that hole is extending into the more densely populated latitudes of northern Europe.

'Fifty per cent of the ozone layer has gone,' said Dr Markus Rex, atmospheric researcher at the German Alfred Wegener Institute, 'Such massive ozone loss has never occurred in the northern hemisphere, its unparalleled.

The risk of acute sunburn is relatively low in Europe, not much greater than a holiday in the tropics. But even low exposure to excess ultraviolet radiation can cause problems especially in children, and lead to risk of skin cancer in later life. Ozone depleted air masses are moving south from the Arctic and have reached Finland. They are expected to move as far east as the Russian-Chinese border and perhaps as far south as the Mediterranean.

Inuit hunters who spend a lot of time outside in the 24 hour daylight that prevails from March are having to wear sunscreen, 'It's not something that we normally have to do, our brown skin is protection enough from the sun usually,' said Theo Ikkummaq, hunter, and wildlife officer in Igloolik, Nunavut, Canada. In lower latitudes, UV sunscreen protection is advised on sunny days until the hole is naturally dispersed by mixing with normal air later in spring as temperatures warm.

Despite the signing of the Montreal Protocol in 1989 to phase out and ban chemicals such as chlorofluorocarbons, or CFCs, which contribute to ozone destruction, a record depletion of the ozone layer, reducing the protective layer 20 kms above the planet's surface by almost 50% has occurred in the Arctic.

It is expected that the Arctic will suffer these ozone hole events during cold winters for the next 50 - 100 years until concentrations of CFC's in the atmosphere fall. The chemicals are now at 95% of their peak levels and the Montreal Protocol is considered an international environmental success story

There is also a connection between climate warming due to greenhouse gas production, and these ozone events. The blanket effect of greenhouse gases is trapping warmer air closer to the planet, creating extremely cold conditions in the upper atmosphere that are conducive to turning CFC'c into aggressive ozone destroying chemicals.

Top Image Credit: Polar stratospheric clouds in the Arctic. Photo Credit: Ross J. Salawitch, University of Maryland