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For a multirate approximation, we have determined the dynamics of rock heating by a magmatic-fluid flow in a flat permeable zone cutting the cratonic lithosphere of the Siberian Platform from a magma chamber at a depth of 50 km to the Earth’s surface. This dynamics is compared with the dynamics of infiltration metasomatism in a three-layer lithosphere section: (1) harzburgitic mantle (depth 50-40 km), (2) crystalline basement (39-7 km), whose composition was simulated by the section of rocks hosting the skarn deposits of the Aldan Shield, and (3) platform cover (6-0 km), with its simplified rock compositions specified on the basis of the rock compositions in the southern and northern parts of the trap area of the Siberian Platform. Numerical modeling of the metasomatic transformation of rocks was performed in a multireservoir flow reactor, using the Selektor software. The initial composition of fluids in a magmatic source varied from highly reduced (water-methane) to ordinary (water-acid) (lg p _O2 from -13.0 to -12.0). The obtained balances of the interacting phases show no significant change in the mass of aluminosilicate rocks in the mantle and Earth’s crust sections and a significant loss of their mass under replacement of carbonate and sulfate deposits.

A member and bed-by-bed division of the Upper Vendian formations in the boreholes drilled in the Baikit anteclise and the Angara fold zone in the west of the Siberian Platform has revealed sedimentation gaps above the Danilovka Horizon and above and within the Tira Horizon as well as amplitude erosion of the sediments. Lower beds appear in the above-gap Il’bokich basal argillaceous-dolomite-marl member of the Katanga Formation of the Danilovka Horizon. The thicknesses of all beds gradually increase from north (Baikit anteclise) to south in the Angara fold zone. The upper members of the Tira Horizon did not accumulate below the gap in the north. The Yurubchen Plateau (uplift) was in this area. South of it, the formation thicknesses increase; there are apparently no gaps in the Beryambinskaya area of the Angara fold zone. The Il’bokich member makes up the top of the Moshakovka Formation but is part of the Danilovka Horizon. The Moshakovka Formation spans the top of the Tira Horizon and the bottom of the Danilovka Horizon. In general, stratigraphic bodies in areas with a rapid increase in the tectonic-downwarping amplitudes have a typical geologic structure.

Methods for phasing of an array of radiation channels for coherent combining of linearly polarized fields of narrowband fiber lasers are considered. The high efficiency of operation of the internal feedback loop based on interference of peripheral sections of radiation (Gaussian beam tails) of the phased channels is demonstrated. This method is easy to implement. It allows scaling the power of optical phased arrays and does not require massive optical elements. Equations for calculation of the optical arrangement for implementation of the feedback loop are presented along with the results of experiment on coherent combining of three beams.

Characteristics of the multiple filamentation domain in air are estimated on the basis of the numerical solution of the nonlinear Schrödinger equation in the single filamentation problem statement. The method of diffraction-beam tubes was used to describe the single filamentation of laser pulses. The effectiveness of this method for interpreting experimental results and predicting effects is shown, which is important when planning experiments. The characteristic size of small-scale intensity inhomogeneities in the laser centimeter-radius beam profile, which form a multiple filamentation domain for femtosecond pulses, is shown to be several millimeters. An increase in the original laser beam radius during telescoping increases the sizes of the initial small-scale intensity irregularities, which increases the filamentation start distance. An increase in initial beam power contributes to the elongation of the filaments and increases their number.

In order to study the wake vortices of landing aircrafts, we carried out an experiment on the airfield of Tolmachevo Airport in 2018, which involved Stream Line lidar, AMK-03 sonic anemometer, and MTP-5 temperature profiler. The limits of applicability of the radial velocity method for estimation of wake vortix parameters from lidar measurements were determinied depending on the aircraft type and the wind turbulence strength. The analysis of the experimental results makes it possible to identify features of the spatial dynamics and evolution of aircraft wake vortices during different states of the surface air layer. In particular, it is found that in the case of low average crosswind speed and moderate wind turbulence, the lifetime of the vortex formed behind a landing large MD-11F aircraft can attain almost 4 min.

An algorithm of optical vortex detection is considered and a computer application based on the algorithm is described. A vortex is localized as a branching point of an interference pattern. As the input data for the application, a BMP-file containing an image of interferogram is used; at the output, we obtain information about the vortex topological charge and coordinates. As is shown, accuracy of the algorithm developed is not lower than that of known analogues, while the amount of information obtained is larger.

The results of calculation of continuum absorption coefficients in IR H₂O spectra in 2400-10000 cm^-1 spectral region are presented. The spectral line contour used in the calculation was obtained in the frame of asymptotic line wing theory and contains parameters of both classic and quantum potentials. Parameters of the classic potential were taken from absorption calculations in 8-12 mm region. Parameters of the quantum potential were derived from fitting to Burch’s data in 2400-2800 cm^-1 region. Calculated data in the H₂O transparency windows are consistent with CRDS measurement data and with high temperature Fourier-measurement data.

Variability of the hydrobiont bioluminescence intensity in the spring and autumn periods along the coast of Crimea and its causes are analyzed based on expedition data and satellite information. It is noted that synoptic and mesoscale eddy processes have a significant impact on the vertical distribution of the intensity of the luminescence of hydrobionts, and they must be taken into account when analyzing the seasonal variability of bioluminescence parameters. The concept of integrated intensity of luminescence of hydrobionts (IILH) is suggested, which allows us to estimate the total hydrobiont biomass in the depth range, under study. It was found that the average IILH in the northern part of the Black Sea in the autumn period was more than 10 times higher than in spring. It is noted that the mesoscale eddy processes have the greatest impact on the IILH in the area of the continental slope area.

The algorithm of reconstruction of the Earth surface reflection coefficients with allowance for radiation polarization is considered. The algorithm was approbated for 5 channels of the MODIS device and three territories: south of the Tomsk region, Moscow region, and Irkutsk region. To estimate the error of the algorithm, test points in the center of coniferous large forest areas in summer season were used. Results obtained using the MOD09 algorithm with and without allowance for radiation polarization and results obtained without atmospheric correction are compared with measurement data considered to be reference ones. The comparison demonstrates that the average values obtained by the suggested algorithm with allowance for polarization are closer to the reference data than those obtained using the MOD09 NASA algorithm in the first, third, and fourth MODIS channels, and the difference on the same order of magnitude is observed in the second MODIS channel. In the eighth MODIS channel, one algorithm is preferable in some situations, and another algorithm is preferable in other situations.

The algorithm for determining cloud optical depth and cloud particle effective radii from MSU-MR daytime measurements on-board the Russian meteorological satellite Meteor-M No. 2 is presented. It is based on the physical principles of using the reflectance at 1.6 and 3.7 mm. The algorithm results are compared with the results of the algorithm developed for the AVHRR radiometer. The comparison shows that the cloud parameters retrieved with the algorithm suggested are within the acceptable limits of accuracy.