Preliminary analysis of observations of the Pinatubo volcanic plume with a polarization‐sensitive lidar

A dual‐polarization lidar aboard the NASA Electra aircraft was used in July 1991 to survey the stratospheric plume from the recent Mt. Pinatubo eruption. Both depolarizing and non‐depolarizing volcanic layers were observed, ranging from 17 to 26 km in altitude. Differences in the depolarization signatures of the layers indicates differences in the composition or physical state of the particles in the layers.