| Atmospheric sulfate has impacts ranging from health concerns to climate change. Traditional photolytic oxidant production channels are not sufficient to account for the observed atmospheric sulfate load. It has been suggested that sulfur oxidation is oxidant dependent, especially in urban areas and during the wintertime. The ozonolysis of alkenes, a dark reaction, could potentially produce additional oxidants HO• and H2O2). This study used MOCCA (Model of Chemistry Considering Aerosols), a zeroth dimension chemical box model to study the potential impact of the ozonolysis of alkenes on the aqueous phase chemistry of sulfur. The study was conducted at mid-latitudes using both winter and summer, urban and remote settings. It was found that during the winter time, the ozonolysis of alkenes can enhance the aqueous oxidation of sulfur by approximately a factor of 20. The impact of ozonolysis was found to be independent of direct HO• yield but linearly dependent with H2O2 yield. While preliminary, results suggest that the impact of the ozonolysis of alkenes can still be felt 4 days after an air parcel has left the polluted urban environment with elevated acidity and aqueous S(VI) levels. During the summer runs, the lack of a growth mechanism in the aerosol component of the model lead to an overestimation of the aerosol acidity. While this led to an underestimation of the impact of ozonolysis, we still calculated a approximately 7 fold increase in the aqueous sulfur oxidation rate. |
