The hole in the ozone layer is a major environmental problem that, thanks to effective international action inspired by scientific knowledge, is usually considered solved.

And, to a large extent, it is, but not quite: this thin shield that protects life on Earth from the Sun's radiation is still slowly recovering, and some chemical processes may weaken it



In fact, and as a new study has just revealed, the compounds released into the atmosphere by forest fires can deplete the ozone layer and make it difficult to repair.

The work has been directed by the prestigious researcher

Susan Solomon

, who was one of the pioneers in the study of the ozone layer in the 80s, when the scientific community managed to remove the compounds that damaged it.

Now, after this historic achievement, she warns by email that

the risk has not yet disappeared, in view of the unexpected process that she has just discovered together with her team


Ozone may continue to recover, but it could slow down in a global warming scenario, she says.

The new research, published today in the journal


, indicates that the smoke columns caused by wildfires trigger a series of chemical reactions in the stratosphere and

contribute to the destruction of ozone


Scientists are now concerned that, as

megafires are becoming more frequent

, the recovery of the ozone layer may slow down.

The warning is not that the ozone hole will return to what it was when it alarmed the world 40 years ago, far from it, but that the effects of climate change can cause reactions that we had not even anticipated and that are very harmful to the atmosphere,

even in a matter that we believed already resolved


"I think the risk today is much lower than it was in the 1980s, and the whole world can be proud of what people everywhere achieved by phasing out the production of ozone-damaging chlorofluorocarbons; and the hole in ozone is slowly starting to heal. It's a real public science policy success story. But I think we're not entirely out of the woods, given

the surprising behavior seen after the 2020 Australian bushfires

, which apparently caused ozone to will reach record low values ​​in some places", details the researcher.

"The fires are expected to become more frequent and intense in the future due to climate change. My best guess is they

won't stop the healing of the ozone layer, but they could slow it down if we continue to warm the planet

as we have been doing. That's another reason to worry about the increasing wildfires, in addition to the impact on human lives, property and ecosystems. This has been a completely unforeseen effect and it is important to continue to quantify and understand it, "says Solomon.

Susan Solomon. Dominick Reuter

The work has analyzed the effects of

the huge fires that devastated Australia between 2019 and 2020

, whose environmental effects have been associated with changes in the chemical composition of the upper layers of the atmosphere, including a decline in stratospheric ozone levels.

In particular, there was a record size of the Antarctic ozone hole, which thankfully returned to normal levels by the end of 2020.

Now, scientists have discovered the mechanism by which the fire ends up affecting the so-called 'good ozone', that is, the one that protects us from ultraviolet rays.

What they have observed is that

the mixture of compounds that the fires transport to the atmosphere

activates the production of chlorine radicals, which cause a chain reaction that destroys ozone.

"We have tested the hypothesis by comparing atmospheric observations with simulation models that include the proposed mechanism," the authors say.

"Our results indicate that the chemistry of wildfire aerosols, while not accounting for the record duration of the Antarctic ozone hole in 2020, does

cause an increase in its area of ​​between 3% and 5%

in the mid-south latitude of the total ozone column".

That is, there may be other mechanisms involved and that should also be studied, but the compounds released by fire are one of them.

To know more


Mario Molina, the Mexican Nobel Prize in Chemistry who saved the ozone layer, dies


Mario Molina, the Mexican Nobel Prize in Chemistry who saved the ozone layer, dies


The depletion of the ozone layer already caused a mass extinction 360 million years ago

  • Writing: AMADO HERRERO Paris

The depletion of the ozone layer already caused a mass extinction 360 million years ago

Solomon, who is now a professor at the Massachusetts Institute of Technology (MIT), has studied the Earth's atmosphere for decades and how human action can alter it with catastrophic consequences.

She is one of the most cited experts in this area in the world and received the BBVA Foundation Frontiers of Knowledge award in 2012.

She led two expeditions in the Antarctic winter, in 1986 and 1987, with temperatures reaching -50ºC, and

her studies have been fundamental to understanding the relationship between ozone and climate


Today, Solomon is still at the foot of the canyon and his latest results will open

a new avenue of research that, once again, will inspire other scientific groups


According to the criteria of The Trust Project

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  • Articles Angel Diaz