Lidar Measurements at Alaska, 1991-1994

Pinatubo Volcanic Effect on Stratospheric Aerosol Layer

Abstract

The concentration of stratospheric aerosols observed with a lidar in Alaska increased from December 1991 to March 1992. The measurements suggested that particulate matter injectedinto the stratosphere through the eruption of Pinatubo (Philippines, June 1991) was transportedto high latitudes and descended there. The speed of descending motion of the aerosollayer in Alaska was about 50 m/day, which is larger than the value in mid-latitudes. Decaytrend of aerosol load disturbed by Pinatubo volcanic eruption was approximately insimillarwith the trend observed in Japan suggesting that global distribution of volcanic aerosols isaffected by dispersion of particles from low and high latitudes and particle descending in highlatitudes.