Idealized modeling of stratospheric aerosol injection deployment scenarios with two non-cooperative actors

Abstract

We investigate solar radiation management scenarios of two non-cooperative actors deploying stratospheric aerosol injection (SAI). We perform the idealized experiments with a four-box Energy Balance Model capable of predicting hemispheric temperatures and monsoon precipitation, coupled to PI controllers. The controller models the behaviour of an actor that deploys SAI at a certain location in order to reach a certain climatic goal, such as an average temperature or a monsoon precipitation target. The goal of this work is to assess through case studies of idealized scenarios what could go wrong in a non-cooperative deployment. Continuous non-cooperative deployment by two actors provides the expected climate result in most of the cases studied, but it can lead to the actors not fully reaching their targets. Intermittent deployment, related to policy instability in our scenario design, can lead to a free-riding situation, or missing the climatic targets due to temperature oscillations induced by the intermittency. These results of our case studies point out the need for exploring more politically plausible scenarios in SRM modelling studies. More complex experiments, including multi-target controllers and coalitions of actors, will be possible with a future version of the model.