This article has more detail on how the 2001 Mount Pinatubo eruption lowered temperatures by 0.6°C : https://earthobservatory.nasa.gov/images/1510/global-effect

This article has more detail on how the 2001 Mount Pinatubo eruption lowered temperatures by 0.6°C : https://earthobservatory.nasa.gov/images/1510/global-effects-of-mount-pinatubo https://earthobservatory.nasa.gov/images/1510/global-effects... There are two mechanisms. 1. The SO₂ combines with water to form aerosol droplets which scatter and absorb incoming sunlight. 2. These droplets break down or drop to Earth over 1-2 years. Which means that if something unforeseen happens it will be gone pretty soon. Also, while SO₂ in the lower atmosphere causes acid rain, the stratosphere is above all that.