During 1991 the terrestrial stratosphere went through a substantially increased aerosol load, due mainly to the eruptions of Mt. Pinatubo in the Philippines, and, to a lesser extent, to those of Mt. Hudson in Chile. This paper reported lidar observations of the stratospheric aerosols at the South Pole. Two layers were present at different altitudes during the austral summer, but only the higher one persisted in the stratosphere until the onset of the polar stratospheric cloud (PSC) phenomenon. Data have been analyzed in terms of the integrated backscattering coefficient and the aerosol mass content has been estimated. ¿ American Geophysical Union 1993