A comprehensive observation-based multiphase chemical model analysis of sulfur dioxide oxidations in both summer and winter

Abstract. Sulfate is one of the main components haze fine particles, and its formation mechanism remains controversial. A lack detailed comprehensive field data hinders accurate evaluation relative roles prevailing sulfate pathways. Here, we analyzed production rates using a state-of-the-art multiphase model constrained to observed concentrations transition metal, nitrogen dioxide, ozone, hydrogen peroxide other important parameters in winter summer North China Plain. Our results showed that aqueous metal ion (TMI)-catalyzed oxidation was most pathway followed by surface Mn both while hydroxyl Criegee radical oxidations contribute significantly summer. In addition, also modeled published cases for fog cloud conditions. It found dioxide dominant higher pH range hydroperoxide ozone dominated cloud.