A German scientist has detected what he says is the first hole in the ozone layer above the North Pole, Markus Rex, Head of the Department for Atmospheric Physics at the German Alfred-Wegner Institute, said on Wednesday.
The ozone layer or ozone shield is a region of Earth’s stratosphere that absorbs most of the sun’s ultraviolet radiation.
It contains high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere.
For the past two weeks, the ozone layer thickness in the Arctic has been below the thickness that defines a hole over the Antarctic, Rex said.
“In the areas where the thickness of the ozone layer is at its maximum, the loss is around 90 per cent,” Rex said.
This covers an area three times the size of Greenland.
In total, an area of 20 million square kilometres, or 10 times the size of Greenland, is affected, even though the loss of ozone is sometimes lower.
According to Rex, this is due to an especially strong polar vortex this winter and low temperatures in the stratosphere, where the ozone layer is located.
“At the moment, those air masses are still enclosed above the central Arctic, which is why people in Europe don’t need to worry about getting sunburned faster than usual.”
However, it’s a possibility that those air masses will drift away from the central Arctic and towards Europe in April.
The production of ozone-damaging chlorofluorocarbons was prohibited a long time ago.
“Without this regulation, this year’s situation would be much worse,” Rex said, adding, however, that the substances were very durable.
The ozone hole above Antarctica, whose discovery in 1985 led to the approval of the Montreal Protocol and therefore, step-by-step prohibition of chlorofluorocarbons, seems to be closing slowly.
In 2019, it reached its smallest extent in about 30 years.
In the Montreal Protocol, signed in 1987, more than 190 countries vowed to reduce the emission of chlorine containing chemicals such as chlorofluorocarbons (CFCs).
A study published around six years ago indirectly called into question the role of CFCs and the Protocol.
“In the project, we successfully answered some of the open questions regarding ozone loss, and we demonstrated that besides the destruction caused by chlorine, no additional chemical mechanisms play a decisive role,” says environmental chemist Dr. Marc von Hobe.
Analyses of air samples at the University of East Anglia and the University of Frankfurt as part of the project showed a clear decrease in stratospheric chlorine. (dpa/NAN)