Lidar Observation of Stratospheric Aerosols Increased from the 2009 Mount Sarychev Volcanic Eruption

Abstract

Lidar observations have been making at Moshiri (44.4°N), Tsukuba (36.1°N) and Lauder (45.0°S) for validation of the GOSAT (IBUKI) products. The lidar data at Ryori (39.0°N) and Kochi (33.6°N) are also used for the GOSAT validation. Thin aerosol layers were observed at an altitude of 20-21km over Japan on 25 June 2009. These aerosol layers are thought to be originated from the Mt. Sarychev (48.08°N, 153.23°E) volcanic eruption on 12 June 2009. About one month after the eruption, the stratospheric aerosols increased several times compared with the background level around 1996 at Tsukuba. The impact of this aerosol layer on the GOSAT product of CO₂ column amount is estimated not to be always negligible. For an optical depth of 0.02∼0.037 of stratospheric aerosols, CO₂ column amount will have a negative bias of 0.3∼0.5% for a surface albedo of 0.1 if we disregard them.