Idealized modeling of stratospheric aerosol injection deployment scenarios with two uncooperative actors

[Geoengineering News]

https://essopenarchive.org/doi/full/10.22541/essoar.173884462.21136288/v1

Authors

Anni Määttänen,François Ravetta,Thibaut Lurton,Olivier Boucher

Cite as: Anni Määttänen, François Ravetta, Thibaut Lurton, et al. Idealized modeling of stratospheric aerosol injection deployment scenarios with two uncooperative actors. ESS Open Archive . February 06, 2025.

DOI: 10.22541/essoar.173884462.21136288/v1

06 February 2025

Abstract

We have coupled multiple Proportional-Integral-Derivative (PID) controllers to a simple climate model to investigate solar radiation management scenarios using stratospheric aerosol injection (SAI). The climate model describes the evolution of hemispheric temperatures and an Indian monsoon index in response to annual SAI at a range of locations. The stratospheric aerosol optical depth evolution after sulfur injections and the monsoon response are parameterized based on simulations with a global climate model. The controller models the behavior of an actor that deploys SAI to reach a certain climatic goal, such as an average temperature or a monsoon precipitation target. We have implemented different deployment scenarios with two actors. Continuous deployment by two actors that do not cooperate sometimes leads to the actors not fully reaching their targets. An experiment where one of the actors stops for a while and then resumes SAI leads to a free-riding situation with one actor doing most of the work. Intermittent SAI experiments, where actors halt deployment for a period due to perceived failure or decision-makers changing their minds, bring about oscillations of hemispheric and global mean temperatures, and the targets are missed. These results emphasize the need for global SRM governance. More complex experiments, including multi-target controllers and coalitions of actors, will be possible with a future version of the model.

Source: ESS Open Archive