Chinese researchers have revealed that increases in methane emissions could have an unexpected positive impact on future ozone recovery, shedding new light on climate governance.

The study, led by researchers from Beijing Normal University, was recently published in the journal Advances in Atmospheric Sciences.

The ozone layer acts as Earth's protective shield, blocking harmful ultraviolet radiation. While international efforts have helped curb ozone-depleting substances, the future recovery of the ozone layer faces new uncertainties due to global warming and human activities.

The research highlights the dual role of methane in ozone recovery. On one hand, methane is a potent greenhouse gas that contributes to global warming, while on the other hand, it has complex chemical interactions in the atmosphere that can help the recovery of the stratospheric ozone layer, explained Xie Fei, a professor at Beijing Normal University.

"Just as ozone can be harmful at ground level but beneficial in the stratosphere, methane and other ozone precursors exhibit similar dual characteristics," Xie said.

"Understanding these dual effects is critical for predicting future ozone recovery and its implications for climate," he added.

The research team conducted experiments to analyze the impacts of methane, carbon dioxide, and sea surface temperature on stratospheric ozone under the Representative Concentration Pathway (RCP) 8.5 scenario in 2050. The RCP 8.5 scenario is a future climate pathway that assumes high greenhouse gas emissions and limited climate mitigation efforts, leading to significant global warming by the end of the century.

The results revealed that rising methane emissions could have a particularly strong positive impact on ozone recovery in both the Arctic and Antarctic regions.

"Our ultimate goal is to provide a comprehensive understanding of ozone recovery pathways and their broader implications," said Xie, adding that they will further refine their models to account for additional factors influencing ozone recovery.

"This will help policymakers and scientists make better decisions to address both ozone layer restoration and climate change," he added.