A COMPARATIVE-STUDY OF SPCTRAL2 AND SMARTS2 PARAMETERIZED MODELS BASED ON SPECTRAL IRRADIANCE MEASUREMENTS AT VALENCIA, SPAIN

Results obtained using the parametric models SPCTRAL2 and SMARTS2 for the urban area of Valencia, Spain, have been analysed and compared wit h experimental measurements at ground level obtained with two Li-cor 1 800 spectroradiometers with a 6 nm resolution. The study used two diff erent input parameters in both models for the aerosol characterisation : the aerosol optical thickness at 0.5 mu m, tau(a lambda(0.5)), and t he Angstrom turbidity coefficient beta. The results obtained show that both algorithms reproduce quite correctly the spectral irradiance exp erimental values when an urban aerosol model parameterised by the tau( a lambda(0.5)) value is considered. In all the cases the deviations ar e lower when SMARTS2 code is used. (C) 1998 Elsevier Science Ltd. All rights reserved.