OZONE ON FIRE

Frequent, widespread forest fires in a warming world are the new threats to the ozone layer

OZONE DAY SPECIAL

THE WILDFIRES that scorched much of Australia from June 2019 to March 2020 were unprecedented in scale and nature. They burned over 33 million hectares, killed or displaced 3 billion animals and caused damage to property, becoming the worst natural disaster in the country. Now scientists say that the fires have also triggered changes kilometres high in the atmosphere, widening the ozone hole.

A group of researchers in the UK have found that the intense and uncontrolled fires resulted in millions of tonnes of smoke and associated gases. "The smoke plumes formed several vortices, the largest of which maintained a coherent and isolated structure for over two months and was eventually detected at altitudes of up to 36 km," notes the study, published in Scientific Reports on August 25, 2022. The smoke plumes rose to such great heights because of black carbon, which absorbs solar heat and rises into the lower stratosphere like a hot-air balloon. The ozone layer sits in the stratosphere, located between 10 km and 50 km above Earth's surface, and absorbs harmful ultraviolet radiation from the sun. Research has linked a decrease in ozone levels to an uptick in the incidence of skin cancer and cataracts in humans.