Ozone‐induced oxidation of SO2 in simulated clouds

Abstract

Cloud chamber experiments were conducted to measure the rate of conversion of gaseous SO₂ to aqueous sulfate under conditions of warm‐cloud formation. The rate of SO₂ conversion in cloudy air with 140 ppb ozone was approximately 1000 times faster than conversion in clouds without ozone. The rates of SO₂ oxidation observed in these experiments with simulated clouds (pH 4.5–5.5) and ozone concentrations in the range of 25–430 ppb are consistent with previously published kinetics for SO₂ in bulk‐water experiments with much higher concentrations of ozone.