|Title||Atmospheric concentrations and the deposition velocity to snow of nitric acid, sulfur dioxide and various particulate species|
|Publication Type||Journal Article|
|Year of Publication||1985|
|Authors||Cadle SH, Dasch JMuhlbaier, Mulawa PA|
A study of deposition velocities to snow was conducted during the 1982-83 and 1983-84 winters at the University of Michigan Biological Station in northern Michigan. Weekly measurements were made of dry deposition rates to snow and the atmospheric concentrations of the deposition species. SO2, with an average concentration of 2.2 ppb, was the dominant atmospheric sulfur containing species. NO2, with an average concentration of 1.8 ppb, was the dominant atmospheric nitrogenous species. NO3- deposition was due primarily to HNO3, which averaged 0.2 ppb. The HNO3 deposition velocity averaged 1.4 cm/s. The SO2 depsoition velocity varied with temperature, averaging 0.15 cm/s for samples with appreciable exposure time above -3C, and 0.06 cm/s for samples which remained below an ambient temperature of -3C. Deposition velocities of Ca+2, Mg+2, Na+, K+ and NH4+ were 2.1, 1.5, 0.44, 0.51 and 0.10 cm/s, respectively. The mass median diameters of these species were 4.4, 2.7, 1.8, 0.9 and 0.46 um, respectively.