Regional peculiarities of vertical distribution of aerosols from the Gobi Desert in the free and lower troposphere of Vladivostok during long-range transport
V.V. Lisitsa1, K.A. Shmirko1, A.N. Pavlov1, O.G. Konstantinov2
1Institute of Automation and Control Prosesses Far Easten Branch of the Russian Academy of Science, Vladivostok, Russia
2V.I. Il'ichev Pacific Oceanological Institute Far Easten Branch of the Russian Academy of Science, Vladivostok, Russia
Keywords: dust aerosol, lidar sounding, depolarization ratio, long-range transport, optical and microphysical aerosol properties
Abstract
The paper presents the results of lidar measurements of the vertical distribution of optical characteristics of dust aerosol from the Gobi Desert in the free troposphere of Vladivostok. The instrument used is an aerosol-Raman lidar with a cross-polarization channel, which provides vertical profiles of a set of (3β + 2α + δ). High values (δа = 0.13÷0.24), typical of submicron dust aerosol particles, are noted in the altitude range 3.00-4.25 km. This altitude range was also characterized by low values of the Ångström parameter (Å = 0.5) and high values of the single scattering albedo ω = 0.98÷0.99. The values of complex refractive index ( m = m r + imi ) in the dust layer were characteristic of dust particles: m r = 1.48÷1.56, mi = 0.001. The effective radius ( r eff) varied within 0.2-0.4 μm with a maximum at an altitude of 3.8 km. The particle size distribution function in the dust layer had a well-defined bimodal structure with a slight excess of the coarse mode over the fine one. The modal radii of the fine and coarse fractions r f = 0.18 μm and r c = 0.8 μm, respectively.
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