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Saharan mineral dust is studied with a neodymium: yttrium-aluminium-garnet (Nd-YAG) backscatter lidar system in Tenerife, Canary islands (28.5 degrees N, 16.3 degrees W). Recent studies have shown the importance of this atmospheric component as a climate forcing agent. This radiative forcing has been quantified between -1 to -2 W/m(2), values comparable in magnitude to the positive forcing attributed to greenhouse gases. The main sources of this kind of aerosols are the arid zones. The dust plumes from sources in North Africa are the most prominent and cover the largest ocean areas (400-700 Tg/year). Lidar techniques allow one to obtain a vertical characterization of the radiative properties of atmospheric aerosols, which is necessary to improve the radiative transfer model. The measurements, which are the first ones obtained with this instrument, have been carried out during Saharan dust episodes. From this data set the ratio backscattering coefficient, R, is obtained using the top to bottom inversion algorithm proposed by Klett [1]. The results for the parallel and perpendicular components of the backscattered light have been compared in order to analyze the depolarization ratio, delta, of the signal.