RETRIEVAL OF ATMOSPHERIC AEROSOL CHARACTERISTICS FROM VISIBLE EXTINCTION DATA AT VALLADOLID (SPAIN)

Ground-based visible spectral extinction data and modelling of atmospheric aerosols has been carried out to retrieve the columnar size distribution function of aerosol particles. By a minimization method the Junge aerosol size distribution function is obtained and compared with that retrieved by an inversion procedure. The Angstrom alpha and beta turbidity coefficients have also been determined. A relationship between the two turbidity parameters has been found for the different atmospheric conditions. As the beta empirical parameter is related to the concentration of aerosol particles, correlations between it and the derived mass loading M of aerosol particles, which depend on the aerosol size distribution, have been established. Results at different atmospheric turbidity conditions are presented which recover the measured aerosol optical thickness with adequate accuracy.