The methodology of integrated ground-based and satellite monitoring of atmospheric aerosols is discussed, and an algorithm for processing data from coordinated lidar and radiometric measurements (LRS) is described. The algorithm was tested to study the altitude profiles of the aerosol parameters in the vicinity of the AERONET stations using data from ground-based solar radiometers and the CALIOP satellite lidar. To verify the results of satellite sensing, coordinated measurements with AERONET network radiometers and ground-based multi-wavelength lidars at the remote sensing stations of the Institute of Physics, NASB (Minsk, Belarus), Institute of Atmospheric Optics, SB RAS (Tomsk, Russia) and KRSU (Teplokluchenka, Kyrgyzstan) were used.

A number of unified photodetector modules providing for recording lidar signals in the wavelength range from 0.26 to 1.6 μm in the modes of analog signals and photon counting are developed on the basis of photomultiplier tubes and avalanche photodiodes. The software is created for control of the photodetector modules, as well as the test bench for measuring their characteristics is designed.

The results of lidar observations of stratospheric aerosol perturbations for the period of July–November 2008 at three lidar stations of the CIS-LiNet network in Tomsk, Minsk, and Vladivostok are presented along with the results obtained in the Gobi Desert during a research expedition. The behavior of stratospheric profiles of the scattering ratio R(H) (ratio of the total aerosol and molecular backscattering coefficient to the molecular backscattering coefficient) is analyzed at different wavelengths characterizing the aerosol stratification in the stratosphere. The transport of air masses in the stratosphere is studied by the method of direct and backward trajectories using the NOAA HYSPLIT model. It is shown that stratospheric aerosol perturbations are connected with explosive eruptions of volcanoes of the Aleutian islands Okmok (53.4° N, 168.1° W; July 12, 2008) and Kasatochi (52.2° N, 175.5° W; August 6–8, 2008).

Multiyear lidar measurements of characteristics of stratospheric aerosol layer, made at midlatitude observatories in Tomsk (56.5°N, 85.0°E) and Minsk (53.9°N, 27.5°E), are analyzed and used to study the processes of long-term relaxation of the aerosol-perturbed stratosphere after powerful volcanic eruptions to background state. The absence of significant seasonal variations of vertical stratification of stratospheric aerosol and exponential altitudinal decrease of aerosol backscattering coefficient are proposed as criteria of background state of stratospheric aerosol layer for Northern Hemisphere midlatitudes.

The dynamics of the optical parameters of stratospheric aerosol produced by the Mt. Pinatubo eruption is given. Measurements were carried out using a two-wavelength lidar with operating wavelengths of 532 and 1064 nm. The processing procedure of the data obtained with two-wavelength polarization laser sounding is described. The aerosol backscattering coefficient and depolarization coefficient at a wavelength of 532 nm and the ratio of the backscattering coefficients taken at two wavelengths are given in the form of isolines in the height-time plane. Possible temporal transformations of stratospheric-aerosol microphysical characteristics governing variations in the optical parameters are discussed.

An experimental investigation of the dynamics of stratospheric aerosol layer following the eruption of Mt, Pinatubo has been carried out at the lidar station of the Stepanov Institute of Physics, Belarussian Academy of Sciences (Minsk, 53.85 degrees N, 27.5 degrees E). Stable regularities in the behavior of the stratospheric aerosol layer following the eruption of Mt. Pinatubo are established from a statistical analysis of vertical profiles of the total-to-Rayleigh backscattering ratio, These profiles are classified and their dynamics are investigated in terms of the profile classes.