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The Heliogeophysical Complex of RAS, which is developing at the Institute of Solar-Terrestrial Physics SB RAS in the Irkutsk region, includes instruments for studying the Sun, the upper atmosphere and the mesostratospheric lidar system (MS lidar) for analyzing the neutral part of the atmosphere from Earth’s surface to the thermosphere (100–110 km altitude). More specifically, the objective of the MS lidar is to measure profiles of thermodynamic parameters of the atmosphere and the altitude distribution of the aerosol-gas composition. To solve these problems, the MS lidar ensures the use of several laser sensing methods at a number of specially selected laser wavelengths in the total range 0.35–1.1 μm. In this case, the following types of scattering are used: molecular, aerosol, Raman, resonance, as well as differential absorption, Doppler broadening and shift of the spectrum of scattered radiation. The article describes the methods used in the MS lidar and the measured atmospheric characteristics.

One of the important applications of lidar techniques is the study of aerosol content and thermal regime of the stratosphere. Such investigations in monitoring mode were initiated at the Institute of Atmospheric Optics since 1986 (for aerosol) and 1994 (for temperature), and are continued to the present. The main attention is paid to studying the annual variations in aerosol content in the stratosphere and sudden disturbances caused by winter stratospheric warming. In this paper we present the results of studying the aerosol content and its vertical stratification and vertical distribution of temperature in the stratosphere over Tomsk for the last three years.

The primary project objective was to accomplish the Complex Aerosol Experiment, during which the aerosol properties should be measured in the near-ground layer and free atmosphere. Three measurement cycles were performed during the project implementation: in spring period (April), when the maximum of aerosol generation is observed; in summer (July), when atmospheric boundary layer height and mixing layer height are maximal; and in late summer – early autumn (October), when the secondary particle nucleation period is recorded. Numerical calculations were compared with measurements of fluxes of downward solar radiation. It was shown that the relative differences between model and experimental values of fluxes of direct and total radiation, on the average, do not exceed 1% and 3% respectively.

The paper presents the results of laboratory experiments on measurement of absorption and extinction of radiation of the overtone СО laser at wavelengths used for sensing of methane and N2O in the mid-IR spectral range with the differential absorption (DIAL) method, as well as the concentrations of the studied gases reconstructed from the analysis of experimentally obtained absorption coefficients.

A unique instrumentation complex of the Institute of Atmospheric Optics SB RAS is presented. The complex has no analogues anywhere in the world, and makes possible simultaneous measurements of a great number of optical, meteorological, and radiative parameters of the atmosphere, as well as characteristics of aerosol and gas composition. The instrumentation complex is based on permanent stations recording numerous parameters of the atmosphere, namely, TOR (Tropospheric Ozone Research) station, Aerosol Monitoring Station, BEC (Basic Experimental Complex), Fonovaya (Background) Station, and stations for receiving satellite images (NOAA, MODIS/TERRA, MODIS/AQUA). An important part of the complex is the Tu-134 aircraft laboratory enabling measurement of atmospheric parameters in the altitude range up to 7 km. In addition, the following instruments are used in experiments: weather balloons, lidars, sodars, sun photometers, Fourier spectrometers, and others. Satellite data are also used for interpretation of data. The article presents an example of complex operation on one measurement day – 22 May 2012. [ABSTRACT FROM AUTHOR]