2014 年 34 巻 3 号 p. 197-204
Volcanic ash particles originating from the eruptions of Mt. Sakurajima (31.59°N, 130.66°E) were observed with Mie lidar at an altitude of 1.6-2.3 km over Saga (33.24°N, 130.29°E) on 21 and 22 August, 2013. The lidar data showed a high depolarization ratio (10-15 %) and a moderately low backscatter wavelength exponent (0.6-0.7), indicating the presence of supermicrometer-sized nonspherical particles. The aerosol optical thicknesses at 500 nm derived from the skyradiometer were 0.12 on 21 August (13 : 50 LT) and 0.40 on 22 August (12 : 50 LT). The Ångström exponent was 0.16-0.49 and the single scattering albedo was 0.73-0.91, indicating the predominance of supermicrometer-sized and moderately absorbing particles.