Closing ozone hole creates problems

The Antarctic ozone hole was once regarded as one of the biggest environmental threats, but previously undiscovered feedback shows that it has actually helped to shield this region from carbon-induced warming over the past two decades.

High-speed winds in the area beneath the hole have led to the formation of brighter summertime clouds, which reflect more of the Sun’s powerful rays.

‘These clouds have acted like a mirror to the Sun’s rays, reflecting the Sun’s heat away from the surface to the extent that warming from rising carbon emissions has effectively been cancelled out in this region during the summertime,’ said Prof Ken Carslaw of Leeds University, who co-authored the research.

‘If, as seems likely, these winds die down, rising CO₂ emissions could then cause the warming of the Southern Hemisphere to accelerate, which would have an impact on future climate predictions,’ he added.

The key to this newly-discovered feedback is aerosol - tiny reflective particles suspended within the air that are known by experts to have a huge impact on climate.