Lidar Observations of the Pinatubo Aerosol Layers

Abstract

Since the explosive volcanic eruption of Mt. Pinatubo on June 15, 1991, extensive lidarobservations have been made in the world. In this paper we review mainly lidar observationalresults obtained by the Effects of the Pinatubo eruption on Climate (EPIC) project from June1991 to April 1994. The first increase of the aerosols from the Pinatubo eruption was observedat 15.7 km over Tsukuba (36.1°N, 140.1°E) on June 28, 1991. From fall 1991, the Pinatuboaerosol particles were effectively transported from the tropical region into the northern hemisphere.The maximum values of integrated backscattering coefficient (IBC) above the tropopausewere obtained over Japan in February 1992. The IBC over Tsukuba in winter of 92/93decreased only about 40 percent compared with the IBC in 91/92 winter, but the IBC in winterof 93/94 decreased largely. The effects of the Pinatubo eruption on atmospheric minor constituentsand climate will be briefly denoted.