Depending on how high in the atmosphere the aerosols are added, they remain aloft for a few weeks to a few years. It's not a long-term commitment to altering th

Depending on how high in the atmosphere the aerosols are added, they remain aloft for a few weeks to a few years. It's not a long-term commitment to altering the atmosphere's composition like burning fossils has been. This is in fact one of the arguments raised against solar radiation management: that the temperature rebound could be terrifyingly rapid if SRM is stopped. But that danger applies to space sunshades too.