Record Display for the EPA National Library Catalog


Main Title Relative Importance to Sulfate Production of Oxidation Pathways and Clouds as Predicted by the Regional Acid Deposition Model.
Author McHenry, J. N. ; Dennis, R. L. ;
CORP Author Computer Sciences Corp., Research Triangle Park, NC. Applied Technology Div.;Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Research and Exposure Assessment Lab.
Publisher 1993
Year Published 1993
Report Number EPA-68-W0-0043; EPA/600/A-93/252;
Stock Number PB94-112885
Additional Subjects Acid rain ; Atmospheric models ; Sulfates ; Oxidation ; Clouds(Meteorology) ; Sulfites ; Atmospheric chemistry ; Air pollution ; Troposphere ; Reprints ; Regional Acid Deposition Model
Library Call Number Additional Info Location Last
NTIS  PB94-112885 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 10p
Recent investigations into the oxidation of S(IV) to S(VI) in the aqueous phase have suggested that clouds play a major role in the production of sulfate in the troposphere. Cloud production of sulfate is accomplished through dissolution of S(IV) from polluted interstitial air and subsequent reaction by dissolved oxidants. A variety of oxidation pathways have been studied. The Regional Acid Deposition Model (RADM) and associated RADM Engineering Model (RADM/EM) incorporate a cloud/aqueous chemistry module that treats convective clouds in the troposphere as batch reactors, using modified Henry's law coefficients to determine aqueous- and gas-phase equilibria among ionic species in the cloud water and interstitial gases. Both precipitating and nonprecipitating clouds are treated. The aqueous mechanism includes oxidation of S(IV) by H2O2, O3, O2 catalyzed by trace metals, methylhydrogen peroxide, and peroxyacetic acid.