Sensitivity analysis of a chemical mechanism for aqueous‐phase atmospheric chemistry

The sensitivity analysis of a comprehensive chemical mechanism for aqueous‐phase atmospheric chemistry is performed. The main aqueous‐phase reaction pathways for the system are the oxidation of S(IV) by H 2 O 2 , OH, O 2 (catalyzed by Fe 3+ and Mn 2+ ), O 3 and HSO 5 − . The HO 2 (aq) and OH(aq) radicals contribute indirectly to this process by producing and consuming H 2 O 2 (aq), respectively. The dominant pathway for HNO 3 (aq) acidity is scavenging of nitric acid from the gas phase. HCOOH is produced because of the reaction of HCHO(aq) with OH(aq). The gas‐phase concentrations of SO 2 , H 2 O 2 , HO 2 , OH, O 3 , HCHO, NH 3 , HNO 3 , and HCl are of primary importance. An increase in the liquid water content of the cloud results in a decrease of the sulfate concentration but an increase of the total sulfate amount in the aqueous phase. A condensed mechanism is derived from the analysis.