A wildfire can carry smoke into the stratosphere, where particles have drifted for more than a year. A new MIT study has found that these particles, when suspended there, can trigger chemical reactions that destroy the protective ozone layer that protects the Earth from the sun’s harmful ultraviolet radiation.

Research published in the journal Nature 8 March focuses on the smoke from the Black Summer megafire that burned in eastern Australia from December 2019 to January 2020. The most devastating fires in the country’s history killed dozens of people. million hectares and released more than 1 million tons of smoke into the atmosphere.

A team from the Massachusetts Institute of Technology has discovered a new chemical reaction that worsens ozone depletion of smoke particles from wildfires in Australia. By causing this response, the fires likely contributed to 3-5 percent depletion of the total ozone layer in the mid-latitudes of the Southern Hemisphere, Australia, New Zealand, and parts of Africa and South America.

The researchers’ model also shows that fires affect the polar regions by eating the edges of the ozone hole over Antarctica. By the end of 2020, smoke particles from bushfires in Australia had expanded the Antarctic ozone hole by 2.5 million square kilometers, or 10 percent of its area from the previous year.

It is unclear what the long-term impact of wildfires will be on ozone recovery. The United Nations recently reported that the ozone hole and ozone depletion worldwide are on the way to recovery, thanks to continued international efforts to phase out ozone-depleting chemicals. But MIT research shows that as long as these chemicals remain in the atmosphere, large fires can trigger a reaction that temporarily depletes the ozone layer.

“The 2020 Australian fires were a real wake-up call for the scientific community,” says Susan Solomon, the Lee and Geraldine Martin Professor of Environmental Studies at MIT and leading climate scientist who first identified the chemicals responsible for the Antarctic ozone hole. . “The impact of forest fires had not been taken into account before. [прогнозах] ozone restoration. And I think this effect may depend on whether the fires become more frequent and more severe as the planet warms.”