Titre : Is There Room for Geoengineering in the Optimal Climate Policy Mix?

Conférencière : Anca Pana (University of Zurich, Suisse)

Résumé :
We investigate geoengineering as a possible substitute for adaptation and mitigation measures to address climate changes. Our analysis relies on the Ada-BaHaMa integrated assessment model that has been enhanced to include geoengineering strategies. We disentangle between the effects of solar radiation management on atmospheric temperature levels and its side effects on ecosystems. To address the variability of the latter we rely on a distributional analysis. Our findings are threefold. First, we show that the joint use of all three climate strategies yields the best results in term of welfare. However, geoengineering entails serious side effects on the environment and its use is optimal in a minority of the analyzed scenarios. Mitigation emerges as the first pillar to address climate change, with adaptation as an effective complement. Second, we find that a climate policy that targets primarily temperature reductions, but does not address the increase in CO2 concentrations, is not sustainable. Addressing this issue reduces the use of geoengineering even further. Third, we show that annual GDP losses rise considerably when sulfur dissipation side effects diverge from estimations, even for short-term horizons. This finding emphasizes once again the shortcomings of geoengineering as a substitute for mitigation.