Watch How We’ve Solved the Ozone Hole Crisis

Note to baby boomers: You did not give up your aerosol-powered spray cans in vain.

Nearly 30 years after an international ban on ozone-depleting substances took effect, the ozone hole in the atmosphere over Antarctica is on a permanent course toward self-repair, scientists say.

That’s a good thing, because the ozone layer absorbs most of the ultraviolet B radiation that the sun sends our way. UVB in excess can cause skin cancer as well as eye cataracts in humans and other mammals.

The science suggests that by 2040, big ozone holes will be a thing of the past, never to grow bigger than the current one (which is about 12.5 million square miles). The hole will continue to shrink after 2040.

The reason for this improvement is that human-made ozone-harming chemicals called chlorofluorocarbons are slowly breaking down in the atmosphere and having less impact on the ozone hole’s fluctuating size, which is also affected by natural changes in temperature and sunlight.

The natural ozone layer in Earth’s stratosphere is several miles thick.

Scientists proved in the late 20th century that CFCs were destroying the ozone layer and threatening all life on Earth.

In 1987, nations signed a global agreement called the Montreal Protocol to end use of these life-threatening pollutants. This example of rising to a crisis stands in stark contrast to the ongoing global disarray over ending pollution from heat-trapping gases such as carbon dioxide, which is the leading driver of climate change.