A new, self-adaptive approach (RAT), at the same time reliable and exportable, has been successfully applied to several environmental emergencies (forest fires, volcanic eruption, etc.). Through this paper its application to volcanic stratospheric aerosol monitoring will be described with reference to the Mount Pinatubo eruption (June 1991) whose stratospheric cloud interested Europe about six months later. By using only NOAA/AVHRR data, the proposed method permitted to trace in time and space the growth and decay of Pinatubo's stratospheric aerosol cloud in good agreement with independent ground based observations.