The repair of the Earth’s ozone layer has been a success, but a new study reveals a downside: ozone is warming the planet up to 40% more than originally anticipated.
Bill Collins from the University of Reading and his colleagues used a computer model to project the amount of warming associated with changes in ozone between 2015 and 2050, taking into account changes in humidity, clouds and surface reflectivity. If we continue to implement the air pollution controls mandated by the Montreal protocol in 1987 their results, which are published in Atmospheric Chemistry and Physics, suggest that the healing of the ozone layer will create more warming, cancelling out most of the climate benefits from stopping production of ozone destroying chemicals such as CFCs and HCFCs.
By 2050 they estimate that ozone will be the second-largest contributor to warming after carbon dioxide.
The researchers stress that repairing the ozone layer is still the right thing to do and brings vital health benefits; protecting people, animals and plants from dangerous ultraviolet radiation. Some of the additional warming effect can be mitigated by reducing air pollution associated with ozone formation near to the ground. However, climate policies need to be revised to take into account the unavoidable extra warming associated with ozone layer repair.
