A new study led by the University of East Anglia reveals that the healing of the ozone hole over Antarctica could help restore the Southern Ocean’s capacity to absorb carbon from the atmosphere. The Southern Ocean, despite its relatively small size, plays an outsized role in mitigating climate change by absorbing a significant portion of the world’s atmospheric carbon.
Scientists have found that the negative impact of the ozone hole on the Southern Ocean’s carbon uptake is reversible — but only if greenhouse gas emissions are rapidly reduced. In the late 20th century, the ozone hole intensified winds over the Southern Ocean, which brought carbon-rich waters to the surface and reduced the region’s ability to absorb additional carbon. As the ozone layer heals, this effect is expected to reverse, potentially allowing the ocean to take up more carbon, provided emissions are kept in check.
The research used advanced Earth system models to simulate different scenarios, including continued ozone depletion, ongoing recovery, and varying levels of greenhouse gas emissions. The findings show that as the ozone hole’s influence fades, greenhouse gas emissions will become the dominant factor controlling how much carbon the Southern Ocean can absorb.
Lead scientist Dr Tereza Jarníková highlighted that the effects of human-caused ozone hole damage on ocean winds, circulation, and carbon uptake are reversible under lower emission scenarios. However, if emissions continue to rise, the ocean’s ability to act as a carbon sink may weaken, regardless of ozone recovery.
The healing of the ozone layer is a direct result of international cooperation, especially the Montreal Protocol, which phased out ozone-depleting substances. This success story demonstrates the potential for global environmental recovery when effective action is taken.
However, experts caution that the future capacity of the Southern Ocean to absorb carbon will depend increasingly on how quickly greenhouse gas emissions are reduced. The study underscores the importance of continued efforts to limit emissions in order to maximise the benefits of ozone recovery for climate regulation.