10/02/2018

'We Might Be Entering The Age Of The Unfailing Sunburn': Ozone Layer Getting Worse In Populated Areas

FairfaxLiam Mannix

The ozone layer is not healing as scientists had hoped. In fact, depressing research released on Tuesday finds our UV-blocking ozone layer is still thinning in more populated parts of the world.
A global effort to cut certain airborne pollutants over the last three decades has been credited with allowing our damaged ozone layer to recover. But the shock new findings – which scientists cannot explain – suggest we may have been celebrating too early.


This image, from NASA and centred on Antarctica, shows the damage we have done to the ozone layer. The gradient indicates the amount of ozone at that region. As you can see, a large area of the atmosphere above Antarctica has been depleted of ozone, as shown by the dark-blue area. Photo: NASA's Earth Observatory
"This study is scary,” said Professor Bill Laurance, a climate change scientist at James Cook University.
“Until we understand what’s really happening you’d be silly to sun yourself, except in polar regions. The era of suntanning could be over; we might be entering the age of the unfailing sunburn."
The ozone layer is crucial to life on Earth. It blocks the sun’s most damaging rays, preventing them from damaging our DNA.
In the ‘70s, we discovered that chlorofluorocarbons – a type of gas used in fridges and aerosol sprays – were destroying the ozone layer, leading to a large hole forming over the Antarctic.
Humanity responded to the crisis, signing the Montreal Protocol in 1987 and phasing out chlorofluorocarbons.
It was the world’s first universal agreement to cooperate on human health, according to University of Melbourne sustainability expert Dr Paul Read, and heralded huge optimism about how we would respond to other worldwide challenges, such as global warming.
It also seemed to work – the hole over the Antarctic has been gradually closing. Scientists hailed it as the only environmental indicator we had managed to significantly improve since 1992.
A study published on Tuesday by a team of researchers from the UK and Switzerland, published in Atmospheric Chemistry and Physics, challenges that.
The researchers found the parts of the ozone layer that stretch over large swathes of the far north and south of the globe – including the southern ocean below Australia – are not recovering at all. There, the ozone layer is continuing to thin.
“The potential for harm in lower latitudes may actually be worse than at the poles. The decreases in ozone are less than we saw at the poles before the Montreal Protocol was enacted, but UV radiation is more intense in these regions and more people live there,” said study co-author Joanna Haigh, Co-Director of the Grantham Institute at Imperial College London.
What this new paper is saying,” said Dr Read, “is that the hole in the ozone layer, predicted to be completely repaired by around 2060, has a whole section that's not repairing itself.”
The finding comes from a huge project to combine data from multiple atmosphere-monitoring satellite missions since 1985. Adding the data together produced a clear finding the layer was continuing to thin.
It is not clear why these parts of the layer are thinning. The study’s authors suggest climate change may be changing patterns of atmospheric circulation, leading to ozone being distributed differently.
There are also a range of other substances that are used in paint strippers and similar chemicals that could be destroying the ozone. It was previously not believed these substances lasted long enough in the atmosphere to damage the layer.

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