Smoke from Australian bushfires depleted ozone layer by up to 5% in 2020, study finds

Particles in bushfire smoke can activate molecules that destroy the ozone layer, according to new research that suggests future ozone recovery may be delayed by increasingly intense and frequent fires.

A study published in the journal Nature has found that smoke from the 2019-2020 Australian bushfires temporarily depleted the ozone layer by 3% to 5% in 2020.

Smoke aerosols, the researchers found, can activate chlorine to form compounds that then destroy ozone molecules.

Dr Martin Jucker, a lecturer at the University of New South Wales who was not involved in the research, agreed that the ozone hole might recover more slowly than expected as the result of more bushfires in future.

Solomon and her colleagues identified that the ozone-destruction process is triggered by hydrochloric acid in the stratosphere dissolving in the smoke aerosols.