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Recent studies have shown that the mineral dust is an important radiative forcing agent although-the role played by this atmospheric compound in the UV-VIS radiative transfer into the atmosphere is still uncertain. To study how these particles scatter the solar radiation it is necessary to accurately know the aerosol phase function. The goodness of different phase functions with the presence of mineral dust have been tested comparing the simulated backscattered radiances in the UV-VIS region using real phase functions and different standard phase function approximations. The real ones have been calculated by the aerosol optical depth data measured with a ground-based solar photometer at Tenerife (28.5 degrees N, 16.3 degrees W) during Saharan dust invasions. From the comparison of these results we conclude that when a unique phase function is used in the radiative transfer model the one term Henyey-Greenstein (OTHG) is the worst approximation whereas the two parameter Henyey-Greenstein (TTHGL) is the best one, with an error of less than +/-10%. (C) 2000 COSPAR. Published by Elsevier Science Ltd.