Ozone hole largest in recent years: Study

Contrary to public perception, the Antarctic ozone hole has been amongst the largest on record over the past three years, new research has found.

The ozone hole above Antarctica has been remarkably massive and long-lived over the past four years and chlorofluorocarbons (CFCs) are not the only things to blame, said researchers in their study published in the journal Nature Communications.

CFCs are greenhouse gases containing carbon, hydrogen, chlorine and fluorine and have been studied to contribute to ozone depletion. The ozone layer in the Earth’s atmosphere blocks the harmful ultraviolet (UV) radiation from the sun to protect people from skin diseases. According to the study’s lead author Hannah Kessenich, PhD candidate at the University of Otago, New Zealand, the team found much less ozone in the centre of the hole compared to 19 years ago. “This means that the hole is not only larger in area, but also deeper throughout most of spring,” said Kessenich. The team analysed the monthly and daily ozone changes, at different altitudes and latitudes within the Antarctic ozone hole, from 2004 to 2022.

“We made connections between this drop in ozone and changes in the air that is arriving into the polar vortex above Antarctica. This reveals the recent, large ozone holes may not be caused just by CFCs,” said Kessenich. The researchers believe that there are complex factors contributing to the ozone hole, even as the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer regulates the production and consumption of man-made chemicals known to deplete the ozone.