SAI has advantages that other approaches don’t have, which is why it is insurance against model uncertainty about the sensitivity of the climate to GHGs. Carbon dioxide removal is much slower acting, will be incredibly expensive and has other costs. The other main proposed form of solar geoengineering involves tropospheric cooling by brightening clouds etc. Uncertainties about this are probably greater than for SAI.
I agree that mitigation should be prioritised.
SAI has advantages that other approaches don’t have, which is why it is insurance against model uncertainty about the sensitivity of the climate to GHGs. Carbon dioxide removal is much slower acting, will be incredibly expensive and has other costs. The other main proposed form of solar geoengineering involves tropospheric cooling by brightening clouds etc. Uncertainties about this are probably greater than for SAI.