Volcanic Clouds from the 2007 Eruption of Jebel at Tair (Yemen) Detected by Ground Based and Space Borne Lidar

Abstract

Volcanic clouds from the eruption of Jebel at Tair (south-central Red Sea, Yemen) on 30th September 2007 were observed by ground based lidar at Nagoya, Japan, and also by the space borne lidar CALIOP. The cloud was found as a non-depolarized cloud layer in the upper troposphere by ground based Mie/Depolarization lidar. By tilted lidar observations from ground it was demonstrated that these clouds were not composed of ice particles. Clouds with similar characteristics were also observed by CALIOP. Some evidence confirmed their origin to be the said eruption. The estimated total mass of the cloud particles by lidar-observed data coincides with the estimated sulfuric acid oxidized from SO₂ included in the volcanic cloud observed by Aura satellite. All of the clouds were observed at altitudes lower than the cold point tropopause for a week after the eruption. Since then parts of the clouds were observed in the stratosphere, indicating transport from the troposphere to the stratosphere.