Question: will the ozone layer be filled

Sarah Harris answered on 19 Nov 2014:

It is possible – in September this year scientists released a report suggesting the ozone layer is actually already beginning to heal itself!

Ozone (which is trioxygen, or O3) is pretty unstable, so it’s constantly being created by UV light and destroyed. Chemicals such as CDC and halons, (which used to be in aerosols and fridges) increase the destruction of ozone, which unbalances the natural cycle of ozone creation and contributes to the holes in the ozone layer.

In the 80’s over 200 countries signed the Montreal Protocol, which meant they would phase out using CDCs and halons. This meant there are less of them in the atmosphere, so levels of ozone could increase. There’s now evidence that the ozone layer is healing itself, and that by 2050 it might be repaired to pre-1980 levels (which is great!). The big hole over Antarctica will take longer than this though, as ozone-destroying chemicals can remain in the atmosphere for some time.