Study of lidar and satellite data on stratospheric aerosols formed due to Mt. Pinatubo volcanic eruption

Abstract

Lidar aerosol backscatter data of a few stations published in <i>Bulletin of Global</i> <i>Volcanism Network</i> (<i>USA)'</i> (Vol. 16, Nos 5-12, 1991) have been used to investigate various transport/dynamical processes and also aerosol loading in the stratosphere due to the 15 June 1991 Pinatubo volcanic eruption. Some recently reported satellite observations have also been used to support the results obtained. Satellite data showed that in the zone extending 10°N from equator, Pinatubo aerosols circled the globe in 21 days, implying a mean easterly speed of 20-22 m/s. Ground-based lidar observations showed that aerosol cloud spread northward faster in low mid-latitudes and slowly in higher mid-latitudes. The stratospheric aerosol loading due to Pinatubo was about 30 times the pre-eruption value at a low latitude station (Mauna Loa) and about 4 times at a higher mid-latitude station (Obninsk). The analysis further showed that the aerosol cloud due to Pinatubo was nearly 1.5 times than that produced due to the 1982 El Chichon volcanic eruption. The presence and morphology of of the multiple stratospheric aerosol layers that appeared over Mauna Loa in the aftermath of Pinatubo are discussed.