Banning ozone-destroying gases such as CFCs has helped the ozone layer to recover, but when combined with increased air pollution the impact of ozone could warm the planet 40 per cent more than originally thought.

A new study led by the University of Reading found that from 2015 to 2050, ozone is expected to cause 0.27 watts per square meter of extra warming. This figure, which measures how much extra energy gets trapped per square metre of Earth's surface, would make ozone the second largest contributor to future warming by 2050 after carbon dioxide.

The ozone layer, which protects Earth from harmful sun rays, also traps heat as it is a greenhouse gas.

Professor Bill Collins, lead author from the University of Reading, said: “Countries are doing the right thing by continuing to ban chemicals called CFCs and HCFCs that damage the ozone layer above Earth. However, while this helps repair the protective ozone layer, we have found that this recovery in ozone will warm the planet more than we originally thought.”

Because restoring the ozone layer provides less climate benefit than previously calculated, it also means that reducing carbon becomes a higher priority.

However, protecting the ozone layer remains crucial for human health and preventing skin cancer. The ozone layer shields Earth from dangerous ultraviolet radiation that can harm people, animals and plants.

---