Research links Australian bushfires to ozone depletion

New international research has shown that smoke from Australia's devastating 2019-20 summer bushfires may be linked to a significant period of ozone depletion.

The study, published in the Proceedings of the National Academy of Sciences (PNAS) journal on Tuesday, found that smoke from the fires blown into the earth's high atmosphere may have resulted in a 1 per cent depletion in the ozone layer -- an amount that would take a decade to naturally recover, Xinhua news agency reported.

The 2019-20 Black Summer bushfires burnt through over 17 million hectares of land across eastern Australia according to the Australian and New Zealand National Council for Fire and Emergency Services (AFAC).

It is estimated that they released 270 million tons of carbon dioxide over just four months.

Director of the Center for Atmospheric Chemistry at the University of Wollongong, Associate Professor Clare Murphy, who was not involved in the study, said this was the first time smoke's impact on the ozone layer had been quantified.

"Given that these really intense fires that are predicted to increase in the next couple of decades, because of climate change, it could be slowing down the recovery of the ozone layer."

She added that while people tend to think of ozone depletion in terms of the Antarctic ozone hole, the smoke from fires could damage the ozone layer closer to home.

"(This) will increase the overall exposure to UV-radiation for Australians and hence may impact the occurrence of skin cancers in future," said Murphy.

Murphy said, however, this is just one small aspect of climate change and it was important to view this single impact within a broader context.

"It shows how (the environmental) system is all linked. But in terms of the impact of the fires, I think it's a small impact compared to the devastation that you see in the lower parts of the atmosphere."

Since the 1980s the ozone hole over Antarctica has steadily been repaired as governments have banned aerosols that were found to cause its depletion. Murphy said ultimately it was an important example of how a concerted effort from governments and people could reverse damage to the climate.

"It's a success story of what can be done for the environment when governments cooperate. And I think it should be held up as an example if people hope that we can do the same for climate change," said Murphy.