The Montreal Protocol, which phased out CFCs to protect the ozone layer, also helped to prevent 0.65°C to 1°C of additional warming according to a modeling exercise. This is due to the impact that more UVB would have had on photosynthesis and carbon storage.
With climate change ramping up, it is expected that there will be increasing demand to find a geoengineering solution to the challenge. This work suggests that the addition of sulfate aerosols to the stratosphere, though having a cooling impact, may not ultimately be a solution since these same aerosols also promote ozone loss.
Note: The Montreal Protocol is regarded as the most successful environmental treaty. There were some unique circumstances that made that true that do not easily apply to many other such global challenges such as fossil carbon emissions.