New Delhi : The Ozone layer above Antarctica has registered a significant recovery as it healed to create a positive global wind movement.
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.
The study has been published in Nature.
Adding to it is massive suspension of industrial operation across the globe, resulting in less pollution and better environment need.
Our planet swirls faster at the high altitudes near poles, resulting in fast air currents, also referred as jet streams. 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.
Nearly a decade ago, the world agreed upon a protocol and the results are significant.
In other words, the impact of the Montreal Protocol appears to have paused, or even slightly reversed, the southern migration of the jet stream. And for once, that's actually good news.
To put the picture in perspective, Australia was on the verge of facing draught like situation as the rainfalls had started shifting away from the coastal areas. If the trend does reverse, those rains might return.
"The 'weather bands' that bring our cold fronts have been narrowing towards the south pole, and that's why southern Australia has experienced decreasing rainfall over the last thirty years or so," says Ian Rae, organic chemist from the University of Melbourne who was not involved in the study.
"The 'weather bands' that bring our cold fronts have been narrowing towards the south pole, and that's why southern Australia has experienced decreasing rainfall over the last thirty years or so," says Ian Rae, organic chemist from the University of Melbourne who was not involved in the study.
"If the ozone layer is recovering, and the circulation is moving north, that's good news on two fronts (pun not intended)."
Still, we may not be celebrating for long. 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.
What's more, in recent years, there's been a surge in ozone-depleting chemicals, coming from industrial regions in China.
"We term this a 'pause' because the poleward circulation trends might resume, stay flat, or reverse," says atmospheric chemist Antara Banerjee from the University of Colorado Boulder.
"It's the tug of war between the opposing effects of ozone recovery and rising greenhouse gases that will determine future trends."
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.
"If the ozone layer is recovering, and the circulation is moving north, that's good news on two fronts (pun not intended)."
Well, there is not much to cheer about it as the carbon dioxide emission has been massive and increasing and when the operations resumes, the things will start to deplenish.
"We term this a 'pause' because the poleward circulation trends might resume, stay flat, or reverse," says atmospheric chemist Antara Banerjee from the University of Colorado Boulder.
"It's the tug of war between the opposing effects of ozone recovery and rising greenhouse gases that will determine future trends."
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.
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