Vertical diffusion of aerosols over a city

Vertical exchange coefficients for aerosol material, K A , were determined from measurements of atmospheric turbidity at λ = 0.5 μ following the motion of air flowing over Cincinnati, Ohio. Values of the coefficient for sensible heat, K H , were also obtained at the same time in some instances. Most of the values of K A were in the range 0.1 × 10 5 to 10 × 10 5 cm 2 sec −1 with a marked seasonal variation of the average values. No significant variation of K A with height (100 to 600 m) was found.