Global efforts to phase out ozone-depleting substances under the Montreal Protocol have led to the replacement of CFCs and halons with HCFCs, HFCs, PFCs and other alternatives and / or processes.

Compliance with the Montreal Protocol has been so successful that scientists are predicting that the depleted ozone layer will recover to the levels of the 1980s by the middle of this century.

Figure above: Ozone layer thickness over the Arctic in 2011 (right) and without Montreal Environmental Agreement (left) Author/Source: Sandip Dhomse

https://wattsupwiththat.com/2015/05/26/claim-severe-ozone-depletion-avoided/

Watch a short video - Climate 101: Ozone Depletion | National Geographic:

https://youtu.be/aU6pxSNDPhs

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