Author(s)

Jin- You Liang and Mark Z. Jacobson

Abstract

We examine factors controlling the photochemical oxidation of SC>2 in tropos- pheric aerosols. Over a range of liquid water contents (3xlO~^g H%O m~^ to 9 g H%O irT^) and pHs (0 to 8), we find that I^C^Caq) and Og(aq) provide the major sinks for SO] in the aqueous phase when pH is below 5 and larger than 6, respectively. OH(aq) may be an important oxidant of SO2 in the aqueous phase when pH is between 5 and 6 and P^O] is depleted in an air parcel. When aero- sols are present during noncloudy days in summer, the aqueous-phase oxidation of SO% is insignificant compared with the gas-phase oxidation of SO^. We find however that the SO% oxidation in wet aerosols may be enhanced in winter or

Keywords