Vol. 24, issue 03, article # 8
Samoilova S. V., Balin Yu. S., Kokhanenko G. P., Penner I. E. Investigation of the vertical distribution of tropospheric aerosol layers, using data of multi-wavelength lidar sensing. Part 3. Spectral peculiarities of the vertical distribution of the aerosol optical characteristics. // Optika Atmosfery i Okeana. 2011. V. 24. No. 03. P. 216-223 [in Russian].Copy the reference to clipboard
Abstract:
Spectral peculiarities of distributions of the backscattering ba(li, z) and extinction sa(li, z) coefficients, as well as lidar ratio Sa(li, z), estimated from the data of multi-wavelength sensing in Tomsk (56°N, 85°E) in the height range from 0.5 to 7.5 km are presented. The Angstrom parameters hi are determined for corresponding coefficients. It is shown that in the boundary layer (except for the internal mixing layer) hb (532/1064) > hb (355/532), and, simultaneously, hs (532/1064) >hs (355/532). Such a distribution of the Angstrom parameters is caused by the prevalence of small particles with mean geometric radius Rf < 0.5 m in the volume distribution. On the contrary, in the free troposphere hb (532/1064) < hb(355/532) and hs(532/1064) < hs (355/532). Hence, Rf > 0.5 m, and the contribution of large particles is governing. The lidar ratio in the boundary layer decreases with the wavelength, the mean values are 59.7 (15) sr at 355 nm, 51.1 (8.3) sr at 532 nm and 47.3 (13.5) sr at 1064 nm. The spectral behavior of the lidar ratio in the free troposphere can be different, the mean values are 50.4 (8.5) sr at 355 nm, 49.5 (5.7) sr at 532 nm and 55.3 (10) sr at 1064 nm. The contribution of the free troposphere into the total aerosol optical depth increases as the BL height decreases, the mean values of the contribution are 22 (17)% at 355 nm, 27 (19)% at 532 nm, and 34 (22)% at 1064 nm.
Keywords:
multi-wavelength lidar, aerosol, boundary layer, free troposphere, Angstrom parameters