AEROSOL FORMATION IN URBAN PLUMES OVER LAKE MICHIGAN *

Results are reported for field measurements of sulfate aerosol formation in urban plumes from Milwaukee, Wis., that were transported over Lake Michigan by westerly winds. Various types of airborne measurements were made of, for example, light scattering, particles larger than 0.01 micron, the total concentration of condensation nuclei, total hydrocarbons, and concentrations of O/sub 3/, SO/sub 2/, NO, NO/sub x/, SO/sub 4/(-), trace metals, nitrate, and ammonium. Data on derived SO/sub 2/ oxidation rates are compared with the results of a chemical kinetics model that simulated the pollutant conditions. It is concluded that rates of SO/sub 2/ oxidation in isolated urban plumes appear to be quite variable, that kinetics modeling is hindered by an inadequate understanding of the free-radical chemistry that is strongly coupled to the NO/sub x/ cycles, and that the free-radical (HO/sub 2/, RO/sub 2/, O/sub H/) concentrations should be measured in real time so that instantaneous rates may be determined for SO/sub 2/ oxidation.

[1]  J. Hales,et al.  Ozone Formation Related to Power Plant Emissions , 1978, Science.

[2]  A. Alkezweeny.  Measurement of Aerosol Particles and Trace Gases in METROMEX. , 1978 .

[3]  R. A. Cox,et al.  Homogeneous oxidation of sulphur compounds in the atmosphere , 1978 .

[4]  A. J. Elshout,et al.  Sulphates and sulphuric acid in the atmosphere in the years 1971–1976 in The Netherlands , 1978 .

[5]  J. Freiberg.  Sulfur dioxide-sulfate relationships in Budapest☆ , 1978 .

[6]  I. Isaksen,et al.  A CHEMICAL MODEL FOR URBAN PLUMES: TEST FOR OZONE AND PARTICULATE SULFUR FORMATION IN ST. LOUIS URBAN PLUME , 1978 .

[7]  D. Miller.  Precursor effects on SO2 oxidation , 1978 .

[8]  J. Bottenheim,et al.  Mechanism of the homogeneous oxidation of sulfur dioxide in the troposphere , 1978 .

[9]  F. Farley.  Reactivity scale for atmospheric hydrocarbons based on reaction with hydroxyl radical , 1978 .

[10]  Rudolf B. Husar,et al.  Sulfur budget of a power plant plume , 1978 .

[11]  D. Powell,et al.  Estimation of transformation rate of SO2 to SO4 from atmospheric concentration data , 1977 .

[12]  W H White,et al.  Formation and transport of secondary air pollutants: ozone and aerosols in the St. Louis urban plume. , 1976, Science.

[13]  Alan C. Lloyd,et al.  Reactivity scale for atmospheric hydrocarbons based on reaction with hydroxyl radical , 1976 .

[14]  D. R. Sears,et al.  Measurements of atmospheric pollutants in the St. Louis area. , 1976, Atmospheric Environment.

[15]  Jørgen Saltbones,et al.  Decay and transformation rates of SO2, as estimated from emission data, trajectories and measured air concentrations , 1975 .

[16]  P. T. Roberts,et al.  Conversion of SO2 to sulfur particulate in the Los Angeles atmosphere. , 1975, Environmental health perspectives.