Tags Current Affairs

Issue

The ozone layer above Antarctica has recovered so much, it's actually stopped many worrying changes in the Southern Hemisphere's atmosphere, according to a new study.

 

Background

A new study suggests the Montreal Protocol, the 1987 agreement to stop producing ozone depleting substances (ODSs), could be responsible for pausing, or even reversing, some troubling changes in air currents around the Southern Hemisphere.

 

Details

• Before the turn of the century, ozone depletion had been driving the southern jet stream further south than usual. This ended up changing rainfall patterns, and potentially ocean currents as well.

• Using a range of models and computer simulations, researchers have now shown this pause in movement was not driven by natural shifts in winds alone.

• In Australia, for instance, changes to the jet stream have increased the risk of drought by pushing rain away from coastal areas. If the trend does reverse, those rains might return.

• While improvements in cutting back our reliance on ODSs have certainly allowed the ozone to recover somewhat, carbon dioxide levels continue to creep upwards and place all that progress at risk.

• Last year, the Antarctic ozone hole hit its smallest annual peak on record since 1982, but the problem isn't solved, and this record may have something to do with unusually mild temperatures in that layer of the atmosphere.

• The Montreal Protocol is proof that if we take global and immediate action we can help pause or even reverse some of the damage we've started. Yet even now, the steady rise in greenhouse gas emissions is a reminder that one such action is simply not enough.