Characterization of Asian dust and Siberian smoke with multiwavelength Raman lidar over Tokyo, Japan in spring 2003

Abstract

[ 1] In the spring of 2003, we observed lofted Asian dust and Siberian forest-fire smoke plumes in the free troposphere over Tokyo, Japan with a dual-wavelength Raman lidar. These data show clear signatures of the optical characteristics depending on the aerosol type. The Asian-dust layer shows that the particle depolarization ratio ( PDR) at 532 nm is -20%, and the extinction-to-backscatter ratio ( lidar ratio) at 355 nm is -49 sr, which is close to -43 sr measured at 532 nm. On the contrary, the smoke layers show that the PDR is as small as 5-8% or less, and the lidar ratio at 355 nm is -40 sr, which is considerably lower than -65 sr which was measured at 532 nm. We also applied an inversion algorithm for the smoke case. The effective radius was -0.22 mm and the single-scattering albedo at 532 nm was -0.95.