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In this work, the long-term series of vertical stratification of aerosol in the stratosphere are processed and analyzed with the use of the scattering ratio as an example, as well as the vertical distribution of aerosol scattering coefficients at a wavelength of 532 (altitude range 15-50 km) over Tomsk. The experimental data were received from regular measurements at the lidar station of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, in 2010-2021. On the basis of the accumulated experimental material, regional features of the intra- and interannual variability of the stratospheric aerosol in Western Siberia were revealed. An optical-aerosol model of the atmosphere is suggested for this region, more adequate to actual conditions are compared to existing ones.

Possibilities of wind speed measurement in the atmospheric layer from 10 to 20 km with a ground-based pulsed coherent Doppler lidar (PCDL) operating on molecular light scattering are numerically studied. Requirements for the parameters of PCDL with sounding radiation wavelengths of 1 and 2 mm for receiving reliable information about the wind speed and direction in the atmospheric layer under study are determined in numerical experiments.

The reasons are found for a decrease in the sensitivity of a TROA (time-resolved optoacoustic) detector in spectrometers with pulsed lasers and of a non-resonant OA detector in spectrometers with cw lasers when buffer gas nitrogen (air) is replaced by hydrogen in mixtures with an absorbing gas. In the first case, the reason is the high speed of sound in hydrogen at an insufficiently wide working frequency band of the microphone. In the second case, the reason for the loss of sensitivity is the low dynamic viscosity of hydrogen, which results in faster pressure equalization in the pre- and behind-membrane volumes of the OA detector chamber for a light pause as compared to heavier molecular gases. Therefore, the amplitude of an OA signal at the modulation frequency of the cw laser radiation increases in proportion to the dynamic viscosity of the gas.

The mixed moments of wind vector components on the turbulent and meso-gamma scales calculated from experimental data obtained in the surface air layer at an altitude of 10 m are compared. The statistics of mixed moments for several months in different seasons of 2021 is presented. The dependence of mixed moments on the wind velocity and temperature stratification in the surface air layer is briefly analyzed. The values of mixed moments formed by the wind field components on the meso-gamma scale are comparable with those formed by the mixed moments of turbulent components of the wind vector.

The simulation results the radiative forcing of smoke aerosol (RFA) at the boundaries of the atmosphere are considered depending on the photochemical evolution of its organic component, illumination conditions, and underlying surface types (water, mixed forest, and snow/ice). An increase in the albedo of the underlying surface and a decrease in the aerosol optical depth can lead to the transformation of the cooling effect into heating at the top of the atmosphere. An increase in the absorbency of aerosol particles is the cause of an increase in RFA at the top of the atmosphere, which is most significant over snow/ice surfaces, while at the bottom of the atmosphere, RFA decreases. As the solar zenith angle increases, the absolute value of RFA decreases as the smoke plume propagates over weakly reflecting surfaces, but with an increase in the albedo of the underlying surface, this dependence transforms into a nonmonotonic one. It is shown that neglecting the transformations of the optical characteristics of organic aerosol can lead to overestimation or underestimation of the radiative forcing of the aerosol at the top of the atmosphere by several times (by several tens of W/m²), and also cause an error in determining the RFA sign.

The design characteristics of the turbulent lidar affecting its thermo-mechanical stability are determined. A comparative description of two different designs is given, where different approaches are implemented to the selection of transceiving optics and receiver detectors and organization of the temperature control system for stabilizing the lidar optical bench. A simulation scheme of a lidar transceiver is suggested, including the calculation of the displacements of optical elements relative to the base points on the optical bench and the ray tracing from the laser into the atmosphere and back. The influence of the temperature gradient between the opposite sides of the optical bench on the operation of the receiving channels is considered. The results of the experimental study of lidars for resistance to temperature changes are presented. Recommendations for improving the design of a turbulent lidar are formulated.

The conditions for generation of red streamers at an atmospheric air pressure of 0.1-10 Torr are experimentally studied. The mode of generation of streamers tens of centimeters in length from the plasma of an electrodeless capacitive discharge is implemented under low pressures. A discharge between metal small-curvature electrodes transforms into a stationary mode, where streamers are not generated, as the pressure and voltage increase. It was confirmed using the ICCD camera that the streamers start from the positive-polarity electrode. The color of the discharge plasma depends on the air pressure in pulsed and continuous discharges and is most consistent with the color of red sprites at a pressure of ~ 1 Torr.

On the basis of 25 years of observations (1990-2014), the types of ecological-cenotic strategies have been determined for laxicaespitose grasses Arrhenatherum elatius and Dactylis glomerata on spoil banks in the Kuznetzk Basin. In 1989-1990, seven agrophytocenoses were created on levelled open-cut spoil banks of “Listvyanskiy” coal mine. Seeding of D. glomerata and A. elatius was carried out on Quaternary and Perm deposits as a part of mixtures of grasses or grasses with legumes. Determining ecological-cenotic strategies was based mainly on revealing the following aspects: above-ground phytomass, projective cover, lifespan, hummock size, numger of generative shoots, ontogenetic spectrum. D. glomerata acts as a violent species in the grass mixtures on deposits of different geological age for the initial 14 years. But D. glomerata is an ecotopic patient species in the grass mixture with Onobrychis arenaria, in sowing with Trifolium pratense, and in the thickened clover-grass mixture (with a higher seeding rate). A. elatius acts as violent species in the grass mixtures on deposits of different geological age for the initial 4-5 years after seeding. During the subsequent years in the grass mixtures, as well as for all years in the mixture with Onobrychis arenaria, A. elatius acts as a phytocenotic patient species. The following features were also noticed. Both species, D. glomerata and A. elatius, persisted in all communities for all years of observatioin. The generative shoots of D. glomerata were emerging rather late, for the 3-4 years of life, which guaranteed fruiting of the shoots. For both species, the ontogenetic spectra laked the senile individuals (and for and A. elatius even the subsenile ones). In particular years, A. elatius was producing large quantities of generative shoots, about 100 per m²; and the numbers of individuals per m² were reaching 800 on account of seedlings.

Data on the species diversity of representatives of the genus Pseudokephyrion Pascher in water bodies of Western Siberia, their distribution by zones and subzones are summarized. To date, 17 species and intraspecific taxa are known for the region, represented by 16 species of the genus Pseudokephyrion from the Dinobryaceae family. Representatives of this family are found in mosaics throughout Western Siberia. A greater number of species (12) were found in the middle taiga; 11 taxa were identified in the forest-steppe zone; in other zones, the number varied from 1 to 5. No species were found in the steppe and forest-tundra. In lakes and streams of various types, 14 species of this genus were identified. To date, 11 species of this genus are known in the watercourses and reservoirs of the Siberian Uvaly Natural Park.

The results of a taxonomic analysis of the lichen flora of the North-Eastern Okhotsk region (Magadan Region), which currently includes 412 species belonging to 1 division, 1 subdivision, 4 classes, 5 subclasses, 15 orders, 45 families and 133 genera, are presented. The majority of the species belongs to the class Lecanoromycetes (404 species or 98 %), which is represented by 4 subclasses - Acarosporomycetidae, Lecanoromycetidae, Ostropomycetidae and Umbilicariomycetidae. The basis of the lichen flora is represented by the Lecanorales order, which unites 10 families, 53 genera and 190 species (46 % of the total species diversity). The average number of species in the family is 9.2 in the studied lichen flora. The level of species richness exceeding this indicator belongs to 12 families, numbering a total of 313 species or 76 % of the flora. The average number of species in a genus is 3. In the studied lichen flora, 24 genera have an indicator higher than this value; they include 235 species or 57 % of the total flora. The largest genus Cladonia in the lichen flora of North-Eastern Priokhotye includes 44 species. The spectrum of the leading families of lichen flora is typical of the lichen flora of the Boreal zone of the Holarctic. Boreal features are indicated by the leading position of such families as Parmeliaceae, Cladoniaceae, Physciaceae, Lecanoraceae, Peltigeraceae, genera Cladonia, Peltigera. The high position in the spectrum of the families Rhizocarpaceae, Umbilicariaceae, Stereocaulaceae, Lecideaceae, including epilithic species, indicates the mountain character of the lichen flora. Thus, the studied lichen flora should be characterized as mountain-boreal.