As a follow-on, I stumbled across a counterfactual simulation study (2009), which found that if CFCs had continued to be used at half the rate use was growing at in the early 1970s, 17% of ozone would be depleted by 2020 and 67% by 2065, to 50-100 DU down from 300-500 DE in 1960.
Another counterfactual study from 2021 gave a worst-case scenario finding (using similar metrics of CFC use as in other older studies) for the effects on plant life:
As a result of these large reductions in net carbon uptake, global terrestrial biomass decreases from 340 Gt C (1976–2005) to 245 Gt C (200–285 Gt C) by the end of the century (not shown).
So a 30% loss in terrestrial biomass. But of course this must be very hard to simulate with high confidence and it represents continuous 3% year on year growth in CFCs through 2099, which is something like a 46x increase from 1970-2099. It seems both unlikely to me that in 130 years of massive plant die-off and increases in skin cancer, that the entire global scientific community would have just failed to figure this one out.
As a follow-on, I stumbled across a counterfactual simulation study (2009), which found that if CFCs had continued to be used at half the rate use was growing at in the early 1970s, 17% of ozone would be depleted by 2020 and 67% by 2065, to 50-100 DU down from 300-500 DE in 1960.
Another counterfactual study from 2021 gave a worst-case scenario finding (using similar metrics of CFC use as in other older studies) for the effects on plant life:
So a 30% loss in terrestrial biomass. But of course this must be very hard to simulate with high confidence and it represents continuous 3% year on year growth in CFCs through 2099, which is something like a 46x increase from 1970-2099. It seems both unlikely to me that in 130 years of massive plant die-off and increases in skin cancer, that the entire global scientific community would have just failed to figure this one out.