Results of Lidar Observations of Long-Range Transport of Dust Aerosol from the Gobi and Taklamakan Deserts to the Troposphere of Vladivostok

Abstract

The results of lidar measurements of the vertical distribution of optical properties of dust aerosol from the Gobi and Taklamakan deserts in the free troposphere over Vladivostok are presented. A Mi-Raman lidar with a cross-polarization channel was used as an instrument, allowing for the retrieval of vertical profiles of a set of (3β + 2ε + δ) three backscattering coefficients (355, 532, 1064 nm), two extinction coefficients, and one depolarization coefficient at a wavelength of 532 nm. A high depolarization coefficient value (δ = 0.13–0.15), characteristic of submicrometer-sized dust aerosol particles, was observed in the altitude range of 3.00–4.25 km for the dust aerosol from the Gobi Desert. For the aerosol recorded from the Taklamakan Desert, this value was δ = 0.14 in the altitude range of 5–10 km. To obtain information on the spatial distribution of microphysical characteristics, an inversion procedure (3β + 2ε + δ) based on the model of randomly oriented spheroids was used. The complex refractive index within the dust layer had values typical for dust particles, with m_r = 1.48–1.56 and m_i = 0.001 for the aerosol from the Gobi Desert, and m_r = 1.51–1.61 for the aerosol from the Taklamakan Desert.