An optimistic lesson for tackling the climate crisis: when you want, you can, as happened with ozone

when it entered into force Montreal Protocol to Reduce Ozone Depletion ProductsReduced consumption of substances such as CFC gases. A sharp decline in the curve as what had to happen in CO2 emissions to tackle the climate crisis. The use of the treaty is a success story as the ozone hole has been repaired.

The protocol was able to significantly reduce the production and use of these products, which, after entering the atmosphere, destroy the ozone layer, which protects the Earth from solar radiation and ultimately allows life. When it came into force in 1989 (negotiated two years earlier), CFC consumption was 127% higher than in 1986. In 2021, it remained at 1.2% compared to the reporting year.

This protocol and the Vienna Convention from which it derives were the first treaties – in 2009 – to gain universal ratification in the United Nations.

All these gases, released over decades, have long lives in the atmosphere. They even exceed a hundred years. For this reason, after its emissions have decreased, the hole in the ozone layer at the poles, especially in the south, continues to form every winter season and then closes in the summer. But the maximum and average size decreases to a protocol after years of growth. According to calculations, the hole could close in 2050.

rhythm healing This atmospheric gap made scientists think in 2018 that it could be resolved in the north by 2030, in the south by mid-century, and by 2060 at any latitude. Some rates have alarmed, such as 2020, when it has increased significantly and recovered to unprecedented levels “because ozone-depleting compounds are still present.

That year, the southern hole extended by 23.5 million square kilometers. “It would be 1.6 million kilometers higher if the stratosphere had chlorine concentrations like in 2000,” explained NASA researchers to assess the utility of the Montreal Protocol, an agreement between all countries not to emit these gases. .

As this treaty has shown, and putting it in relation to climate change: if you want, you can.