WORLD’S SUCCESSFUL PLEDGE TO FIX THE OZON LAYER
The latest Scientific Assessment of Ozone Depletion, completed in 2018, shows that parts of the ozone layer have recovered at a rate of 1-3% per decade since 2000. It is estimated that up to 2 million cases of skin cancer worldwide may be prevented each year by 2030.
The ozone layer starts about six miles above Earth. It is a colourless form of a specific type of oxygen molecule that protects Earth from ultraviolet rays that can cause skin cancer, eye problems and crop damage.
How was it being damaged by humans?
The chlorofluorocarbons (CFCs) effectively began eating away at the ozone. CFCs were found in things like spray cans, fridges, foam insulation and air conditioners. As a result, in 1985 a gaping hole in the ozone over the South Pole was discovered.
How bad did it get?
At its worst in the late 1990s, about 10% of the upper ozone layer was depleted. But since 2000, it has begun to increase again by about 3% per decade, according to the UN report.
How did things turn around?
In 2016, scientists discovered that the agreement was working. The ozone layer was healing. Using a combination of measurements from satellites, ground-based instruments and weather balloons, a team of scientists found that since 2000 the hole has shrunk by 4 million square kilometres – an area bigger than India. The Montreal Protocol could be the single largest real contribution the world has made so far towards keeping the global temperature rise “well below” 2 degrees Celsius. This is the target agreed at the Paris climate conference in 2018. At current estimates, the hole will close completely around the middle of this century.