It is called "Stratospheric Aerosol Injection" AKA Geoengineering.
https://en.wikipedia.org/wiki/Stratospheric_aerosol_injection_(climate_engineering)
It is called "Stratospheric Aerosol Injection" AKA Geoengineering.
https://en.wikipedia.org/wiki/Stratospheric_aerosol_injection_(climate_engineering)