A simplified planetary energy-balance model: greenhouse forcing drives warming toward a baseline target, while stratospheric sulfate aerosols raise Earth's albedo and offset part of it — the mechanism behind volcanic cooling (e.g. Pinatubo, 1991).
AOD' = inject_rate * 0.05 - AOD * 1.0 (per sim-year)
cooling = k * AOD
T' = (baseline_warming - cooling - T) * 2
- Injection rate — how fast reflective aerosol mass is added to the stratosphere.
- Baseline CO₂ / warming — greenhouse forcing the aerosol layer must offset.
- Sudden stop — aerosols fall out of the stratosphere in a year or two; if injection stops, cooling vanishes fast while CO₂ forcing hasn't — a rapid "termination shock" rebound.
Regional cooling is stronger near the poles than the tropics in this model, matching how SAI proposals are expected to disturb rainfall and temperature patterns unevenly across the globe.