Retrieval of the optical properties of aerosols from aureole and extinction data.

Solution of the small-angle approximation of Weinman et al.1 is piled on the solution of the truncation approximation to synthesize the intensity field in the solar aureole. Accuracy within ±3% is attained for almost all parts of the sky and for air masses less than ∼5. An iterative algorithm utilizing this calculation scheme is applied to the spectral aureole and extinction measurements to estimate the forward parts of the aerosol phase functions and to retrieve the aerosol volume spectra from them.

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