ATMOSPHERIC RO(X) RADICALS AT AN URBAN SITE - COMPARISON TO A SIMPLE THEORETICAL-MODEL

Atmospheric RO(x) radicals (HO + HO2 + RO + RO(2)) were measured for 1 month in the summer of 1993 in Denver, CO. The results are correlated with solar UV fluxes and ozone mixing ratios monitored during the same period. The RO(x) radical measurements were also compared to predictions from a simple computer simulation. Significant free radical levels were observed during the early evening and nighttime and are believed to arise from the HO radical produced by the reactions of ozone with ambient alkenes. Within the error bars of the measurements and approximations and assumptions in the calculations, the data appear to be in accord with the theoretical model.