Estimation of dry deposition of inorganics using filter pack data and inferred deposition velocity

The National Oceanic and Atmospheric Administration Air Resources Laboratory's multiple-layer canopy resistance model for determination of deposition velocities is used to improve estimation of dry deposition fluxes. Weekly averaged concentrations of sulfur dioxide, nitric acid vapor and selected inorganic components of the small particles were measured at a number of sites in Minnesota over a three-year period and their hourly dry deposition velocities inferred using the model. The Minneapolis-St. Paul metropolitan area showed the highest dry deposition for all substances, with concentrations declining with increasing distance from the metro area.