This PDF file contains the front matter associated with SPIE Proceedings Volume 10466, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

The problem of radiative transfer in the ro-vibrational molecular bands under condition of local thermodynamic equilibrium breakdown in a planetary atmosphere is generalized for the case taking into account the extinction (i.e. scattering and absorption) of the continuum radiation produced by aerosols. The method for calculating the nonequilibrium populations of vibrational states of gas molecules in the planetary atmospheres is developed. Formation of the values of the non-equilibrium populations of the excited vibrational states of the CO₂ molecules (in the application to the atmosphere of Mars) within the framework of the model of radiative transfer in the near-infrared bands of this molecule taking into account the extinction of radiation in the continuum produced by aerosol particles has been investigated for the first time. The most complete optical model of the CO₂ and CO molecules is used. A distinctive feature of this model is the detailed accounting of the overlap in frequency of the lines in the spectral range of 1.05–15 μm, which belong to all ro-vibrational transitions of different isotopologues of the CO₂ and CO molecules included into the optical model, as well as accounting for the reflection of radiation by the surface of the planet.

The altitude profiles of ozone concentration are retrieved from measurements of the volume emission rate in the 1.27 μm oxygen band in the TIMED-SABER experiment. In this study we compare the methods of retrieval of daytime [O₃] altitude profile in the framework of two models: electronic-vibrational kinetics and a purely electronic kinetics of excited products of ozone and oxygen photolysis. In order to retrieve the [O₃] altitude profile from the measurements of the intensity of the O₂ band in the region of 1.27 μm correctly, it is necessary to use the photochemical model of the electronic-vibrational kinetics of excited products of ozone and oxygen photolysis in the mesosphere and lower thermosphere.

In this work the temperature dependences of the integrated intensities of the absorption bands of the asymmetric top molecules – H₂O, H₂S, SO₂, and NO₂ were analyzed. A different view of the temperature dependences was shown for cold bands including fundamental ones. For calculating the integrated intensities, the spectral line intensities were used from the known and author’s spectroscopic databases. The reasons are discussed which lead to increasing and decreasing the integrated intensities at high temperatures (T>300 K).

In this work the contributions from the hot bands in the total absorption of H₂S, SO₂, and NO₂ were calculated at temperatures of 300 – 1000 K. The high-temperature spectroscopic databases of the authors were applied for calculating the sum absorptions. The reasons of the different contributions from the cold and hot bands in the absorption spectra of the considered gases are discussed.

The study is dedicated to the problems of wavenumber calibration of multichannel Raman spectrometers. We present a calibration method based on the combined use of the neon emission spectrum and pure rotational lines of the hydrogen Raman spectrum.

The present work focuses on the influence of CH₄ environment on the changes in Raman spectra of n-C₅H₁₂ and i-C₅H₁₂ in the gaseous phase. It was found that in binary gas mixtures with an overwhelming content of CH₄, the majority of the n-C₅H₁₂ and i-C₅H₁₂ Raman bands shifted toward lower wavenumbers. Moreover, there is also a redistribution of intensities between certain Raman bands of n-C₅H₁₂ and i-C₅H₁₂. The obtained results will be essential for Raman diagnostics of natural gas composition.

The paper presents an original statistical algorithm for calculating the mean intensity of solar radiation in broken clouds I , taking into account the sphericity of the atmosphere. The algorithm is based on numerical averaging of the radiative transfer equation and introduction of an additional randomness (randomization). We discuss the results of numerical experiments, carried out to estimate the effect of statistics (numbers of cloud realizations and photon trajectories in a single realization) on the accuracy of the I calculations and laboriousness of the algorithm under different observation and illumination conditions.

The RKR potentials of six isotopologues of the hydrogen chloride molecule in the ground electronic state are calculated on the basis of previously determined values of the Dunham parameters Y_mj up to v = 20 vibration level. The main isotopologue potential was approximated by the expansions of the z_D = (r/r_e-1) and z_S = (1- r_e/r) variables. Obtained results are compared to available literature data.

Estimations of self-broadening, air-broadening and CO₂-broadening coefficients of the main isotopic modification of H₂S are performed. The result is presented as formulae describing the dependence of self-broadening, CO₂- broadening and air-broadening coefficients on rotational quantum numbers of the lower state of a transition. The comparisons of our estimated self-broadening coefficients values with those from the HITRAN and GEISA databases are presented.

Self-, CO₂-, N_2-broadened line widths of NO₂ molecule have been obtained at the room temperature for ~400 000 lines, rotational quantum numbers vary in the range: J to 70 и K_a to 20. The temperature exponents for every line were calculated. The data have been evaluated theoretically in the frame of two methods: semi-empirical approach based on analytical expressions and including a few-parameter correction to account for the real curved trajectories and averaged energy differences method. Being validated by comparison with measurements, these approaches were used to compute extensive line list which could be useful for atmospheric, astrophysical applications and spectroscopic databases.

Estimations of the effect of modern ozone absorption cros-ssections data on calculation of the atmospheric transmission and fluxes, measured using Sun photometers in the UV spectral region, are made. The ozone absorption cross-sections, often used in radiative codes, and new data of Serdyuchenko et al. are considered.

Small sets of chemical reactions involving four water monomers with real values of the rate constants and concentrations are discussed. The steady states and the molecular complex concentrations as functions of the total concentration and the rate constants of the reactions between dimers are examined. It is found that the concentrations of complexes in their approach to a steady state pass through a state with very slowly changing concentrations.

An approach is suggested to the formation of applied ontologies in subject domains where results are represented in graphical form. An approach to systematization of research graphics is also given which contains information on weakly bound carbon dioxide complexes. The results of systematization of research plots and images that characterize the spectral properties of the CO₂ complexes are presented.

The water vapor line broadening and shift coefficients of H₂O absorption lines induced by hydrogen pressure were measured using a Bruker IFS 125HR spectrometer.

The global fitting of the experimental energy levels of unresolved Λ-doublets for the ground state of ¹⁴N¹⁶O molecule is done. The dataset of 1789 experimental energy levels covering the 0-35665 cm^-1 interval for 23 vibrational states was obtained using the fundamental Rydberg-Ritz combination principle. A global model of analysis with vibrational dependences of the parameters of the effective Hamiltonian was used for the theoretical treatment of the diatomic molecule in ²Π electronic state. As a result of the fit a set of the "Dunham-type" molecular parameters was obtained. They reproduce the dataset of the experimental energy levels to the precision of the experimental ones. The found set of the parameters was compared with previous set determined by C.Amiot.

In the report a review is given and new results obtained at the IAO SB RAS on problems of optical communication on scattered laser radiation in the atmosphere and water media are presented. Examples of its implementation are presented under various optical-geometrical conditions and with high quality of field experiments at distances up to 70 km in the atmosphere and up to 25 m in the water medium.

The paper presents experimental data on electromagnetic radiation propagation at a frequency of 5.2 GHz through pine needles at negative temperatures. Hysteresis of electromagnetic losses under a temperature cycling in the range from -10 to -30°С is revealed. Variations in the signal power at the same temperature and mean attenuation of 3 dB reach 1.6 dB. This effect should be taken into account under remote sensing of coniferous forests in winter.

The results of the measurements of astroclimate characteristics in Special Astrophysical Observatory of RAS (SAO, North Caucasus) in 2012 and 2016 are presented. Experimental researches of turbulence structure in the dome specialized room of the Big Telescope Alt-Azimuthal (BTA) at the closed and open dome are executed. Research of distribution of velocities of the airflows movements in points on the volume of dome space is made and the experimental picture of air-flows is restored. Presence in the dome room of BTA of large vortex coherent structure that improves the images quality of the telescope is established.

The results of the measurements astroclimate characteristics in Special Astrophysical Observatory of RAS (SAO, North Caucasus) in 2012 and 2016 are presented. The results obtained from long-term series of observations of day and night astroclimate in SAO. Presence over the territory of the SAO of coherent turbulence in which the image quality of telescopes improves is established. The influence of the type of underlying surface and the direction of wind speed on the mode of appearance of coherent turbulence is found out. It was found that the reason for its appearance is the mountainous terrain and uneven heating of the underlying surface.

The structure of air turbulent motion inside the closed dome room of Big Telescope Alt-azimuth at Special Astrophysical Observatory of the Russian Academy of Sciences (RAS) has been experimentally and theoretically studied. Theoretical results have been reached by numerical solving of boundary value problem for Navier–Stokes equations. Solitary large vortices (coherent structures, topological solitons) are observed indoors. Coherent breakdown of these vortices leads to the coherent turbulence. In the case of identical boundary conditions the pattern of air motions as a result of the simulation and the pattern, registered experimentally using the compact portable ultrasonic weather station, are practically the same.

In the given article mean intensity of a fundamental Bessel-Gaussian optical beam in turbulent atmosphere is studied. The problem analysis is based on the solution of the equation for the transverse second-order mutual coherence function of a fundamental Bessel-Gaussian beam of optical radiation. Distributions of mean intensity of a fundamental Bessel- Gaussian beam optical beam in longitudinal and transverse to a direction of propagation of optical radiation are investigated in detail. Influence of atmospheric turbulence on change of radius of the central part of a Bessel optical beam is estimated. Values of parameters at which it is possible to generate in turbulent atmosphere a nondiffracting pseudo-Bessel optical beam by means of a fundamental Bessel-Gaussian optical beam are established.

According to the work plan for the RSF project, during 2016 measurements were taken in all seasons of the year: February, April, May, August and October. With the use of the whole set of equipment of the stand on the BSVT, the task was set to work out methods for recording and correcting the distortions of the phase of optical radiation passing through a layer of turbulent atmosphere. Complex on-site meteorological observations were organized and conducted at the site of the BSVT. Observations were carried out with the aim of developing and improving the local computational model of turbulent characteristics in the entire thickness of the active atmosphere in the "optical turbulence" range, including the surface layer. As the initial meteorological information for calculations, the model uses two-level data of pulsating observations of temperature and wind speed at the BSVT site, as well as current NCEP/NCAR archival data for the period from 1948 to 2015.

Simultaneous measurements of wave-front aberrations for coherent and incoherent radiation were carried out under conditions of urban atmospheric turbulence on a horizontal track measuring 103.9 m at an altitude of 10 m above the underlying surface. As a luminous object, a metal disk with a diameter of 12 mm was used with holes in which the luminous ends of the optical fibers were fixed.

Measurements of the wave front aberrations at the input aperture of the Big Solar Vacuum Telescope (LSVT) were carried out by a wave-front sensor (WFS) of an adaptive optical system when the controlled deformable mirror was replaced by a plane one.

In this article the coherence of a fundamental Bessel-Gaussian optical beam in turbulent atmosphere is analyzed. The problem analysis is based on the solution of the equation for the transverse second-order mutual coherence function of a fundamental Bessel-Gaussian optical beam of optical radiation. The behavior of a coherence degree of a fundamental Bessel-Gaussian optical beam depending on parameters of an optical beam and characteristics of turbulent atmosphere is examined. It was revealed that at low levels of fluctuations in turbulent atmosphere the coherence degree of a fundamental Bessel-Gaussian optical beam has the characteristic oscillating appearance. At high levels of fluctuations in turbulent atmosphere the coherence degree of a fundamental Bessel-Gaussian optical beam is described by an one-scale decreasing curve which in process of increase of level of fluctuations on a line of formation of a laser beam becomes closer to the same characteristic of a spherical optical wave.

In this work the question of stability of the vortex Bessel-Gaussian optical beams formed in turbulent atmosphere is theoretically considered. The detailed analysis of features of spatial structure of distribution of mean intensity of vortex Bessel-Gaussian optical beams in turbulent atmosphere are analyzed. The quantitative criterion of possibility of formation of vortex Bessel-Gaussian optical beams in turbulent atmosphere is derived. It is shown that stability of the form of a vortex Bessel-Gaussian optical beam during propagation in turbulent atmosphere increases with increase of value of a topological charge of this optical beam.

In this paper the theoretical research of coherent properties of the vortex Bessel-Gaussian optical beams propagating in turbulent atmosphere are developed. The approach to the analysis of this problem is based on the analytical solution of the equation for the transverse second-order mutual coherence function of a field of optical radiation. The behavior of integral scale of coherence degree of vortex Bessel-Gaussian optical beams depending on parameters of an optical beam and characteristics of turbulent atmosphere is particularly considered. It is shown that the integral scale of coherence degree of a vortex Bessel-Gaussian optical beam essentially depends on value of a topological charge of a vortex optical beam. With increase in a topological charge of a vortex Bessel-Gaussian optical beam the value of integral scale of coherence degree of a vortex Bessel-Gaussian optical beam are decreased.

The dynamics of turbulent characteristics including air index refraction vertical variations as well as effective turbulent velocity important for the functioning of the Large solar vacuum telescope (LSVT) adaptive optics system is considered. Long-term changes of the effective turbulent velocity and Fried radius in the atmospheric layer from 0 to 20 km are estimated using model of turbulence taking into account the shape of the energy spectrum over a wide range of spatial and temporal scales. The possible experimental local model of Fried radius changes is discussed for the Large solar vacuum telescope site.

The work discusses the spatial scales of atmospheric optical distortions including the outer scale of turbulence and the Fried radius. It is assumed that the energy spectrum of atmospheric turbulence is not limited strictly [6] and the outer scale is considered in application to astronomical telescopes. In the case when the telescope diameter is larger or comparable with the outer scale the optical distortions substantially differ from the results of the Kolmogorov model. For a given diameter it is possible to introduce a certain spatial scale at distances larger than the size of which the refractive index fluctuations no longer have a significant effect on the quality of astronomical images. Estimates of the outer scale of turbulence are reported for both a atmospheric layer from 0 up to 20 km and surface layer.

The resolution of an adaptive optics system consists in its ability to form and implement the control of a corrected wavefront with a given speed and within the finite range of spatial scales of random inhomogeneities of light field. In result of spatial and temporal limitations appear errors that is affect the efficiency of adaptive correction of turbulent distortions of optical radiation. On the basis of numerical experiments criteria were obtained criteria that allow to make estimated characteristics of all stages of adaptive correction.

The statistically optimal control algorithm for the correcting mirror is formed by constructing a prediction of distortions of the optical signal and improves the time resolution of the adaptive optics system. The prediction of distortions is based on an analysis of the dynamics of changes in the optical inhomogeneities of the turbulent atmosphere or the evolution of phase fluctuations at the input aperture of the adaptive system. Dynamic properties of the system are manifested during the temporary transformation of the stresses controlling the mirror and are determined by the dynamic characteristics of the flexible mirror.

To stabilize the image on the input aperture of the adaptive optics system, a model of the control device for the general angle of inclination of the wavefront is created. The device designed to eliminate image jitter due to atmospheric turbulence and the vibrations of the telescope itself makes it possible to control both the overall wavefront slopes at the input aperture of the system and the wavefront shift along the propagation axis of the beam. For testing the device, a program has been developed that simulates the angles of the wavefront inclination during the formation of an optical beam whose position at the input aperture of the adaptive system is unstable under the influence of atmospheric turbulence.

In this paper the results of simulation are presented of multichannel radiation propagation under conditions of thermal blooming, and correction for nonlinear thermal distortion on the base of the beam phase control is considered. The results demonstrate dependence of correction effectiveness on number of channels and on precision of a reference beam phase reconstruction. Addition increase of effectiveness is possible with adjustment of amplification in the channels of the optical system, i.e., with the use of amplitude-phase control of radiation..

Due to the fact that the cloudiness plays a critical role in the Earth radiative balance, the study of the distribution of different types of clouds and their movements is relevant. The main sources of such information are artificial satellites that provide data in the form of images. The most commonly used method of solving tasks of processing and classification of images of clouds is based on the description of texture features. The use of a set of local binary patterns is proposed to describe the texture image.

The problem of taking into account the effect of polarization is considered for correction of satellite images of the Erath’s surface in the visible wavelength range for the distorting effect of the atmosphere. A program complex for calculation of the radiation components forming the satellite images has been developed with and without allowance for radiation polarization in the approximation of the homogeneous surface. Conditions are considered under which the neglect of polarization properties of radiation can lead to significant errors in reconstruction of the reflection coefficients of weakly reflecting surfaces.

The report solves the inverse problem of diagnostics of inhomogeneous plasma through spatial field processing in the form of inverse double weighted Fourier transform (DWFT). As an inhomogeneous medium, we use a model in the form of three Gaussian irregularities. We examine the influence of dimensions of receiving-transmitting aperture system on diagnostic results.

The authors discuss problems of constructing a multi-site system for lightning activity monitoring aimed at analyzing the structure of tropical cyclones using a network of receivers of VLF radio signals. We propose a functional scheme for the construction of a monitoring system, which includes a functional block to synthesize the system structure, using the existing authorial multi-agent bio-inspired algorithm for synthesizing the sensor network structure.

Based on the numerical solution of the parabolic wave equation for the complex spectral amplitude of the wave field by method of splitting into physical factors the propagation of broadband pulsed optical beam taking into account absorption lines of atmospheric gases is studied. It is found that the influence of absorption lines on the propagation of short pulsed laser radiation whose spectrum coincides with the centers of strong absorption of the atmosphere spectrum in the intervals between weak absorption lines is insignificant.

The mean intensity, intensity fluctuations, and regular and random displacements of optical beams propagating through a zone of increased density formed at subsonic airflow about a turret in the turbulent atmosphere have been analyzed. It has been shown that the presence of perturbations around a turret due to the subsonic velocity of aircraft affects slightly the studied characteristics of the beam. Data illustrating changes in the studied beam characteristics for paths of different geometry and different turbulent conditions of radiation propagation are presented.

In this paper, an optical model of a shock wave is constructed, which is formed by the supersonic flow of air in the flowing of an ogival-shaped body. The average values of the gas flow parameters were calculated from the Navier- Stokes equations using the Fluent 6.0 package taking into account the compressibility of the gas. The results of numerical simulation of the propagation of a laser beam through a shock wave formed during supersonic flow around an ogival-shaped body are presented.

The double weighted Fourier transform method is used to find the average field, scintillation index, mutual coherence function, and intensity correlation in a randomly inhomogeneous multiscale medium. It is noted that the results obtained taking into account second-order effects are consistent with the results obtained with the path-integral method.

Based on numerical solution of the parabolic wave equation for the complex spectral amplitude of the wave field by method of splitting into physical factors the propagation of the superposition of broadband pulsed laser Laguerre- Gaussian beams in a turbulent atmosphere has been studied. It has been found that the difference in the energy density fluctuations of the axial superposition of several modes and one mode, the value of which is determined by the sum of the topological charge magnitudes, of pulsed Laguerre-Gaussian beams at the same turbulent conditions on the propagation path within the statistical error is the same.

Impulse response of non-line-of-sight atmospheric communication channels at wavelengths of 0.3, 0.5, and 0.9 μm are compared for the case in which the optical axes of the receiver and laser radiation lie in the plane perpendicular to the Earth’s surface. The most efficient communication channel depending on the base distance is determined. For a wavelength of 0.5 μm and a concrete variant of the transceiving part of the communication system, the limiting communication range and the limiting repetition frequency of pulses that can be transmitted through the communication channel are estimated.

Measurements of the distribution of probability density of fluctuations of the scattered radiation focused laser beam (0.63 μm) in the near-ground atmosphere in rain, drizzle and fog on the path length 130 m. It is established that the distribution of probability density unimodal and has a right skewness, standardized skewness and kurtosis increase with the growth of the scattering coefficient at close atmospheric conditions (with close values of the normalized variance and diameter (size) of the precipitation particles). The normalized skewness and kurtosis increase with the growth of the diameter (size) of particles of precipitation at close values of the coefficient of scattering. The shape of the distribution does not depend on the wind speed and its the perpendicular component to the path at close atmospheric conditions, at close values of the scattering coefficient. Most of the experimental distributions of probability density are approximated by a generalized gamma - distribution.

The transverse structure formation processes of a laser beam after multiple filamentation were investigated. It is shown that the spectra of post-filamentation light channels (PFC), rings and beam differ substantially. The spectrum of PFC has a significant and symmetrical spectral broadening and covers a range of 600-1100 nm. The broadening of the spectrum of the rings is asymmetric and is directed mainly to the short-wavelength region of the spectrum. The broadening data are stable and do not change when moving away from the multiple filamentation zone. The annular structure of radiation in the cross section of the beam is formed around individual filaments within the region of multiple filamentation, and at a distance of tens of meters from it begins to form a common ring structure surrounding postfilamentation channels.

The paper presents the results of the Helmholtz equation solution by the method of perturbation theory in the spherical coordinate system for the Debye potentials for weakly heterogeneous media based on metal nanoparticles and the dielectric matrix. In that case, the dielectric function of a composite changes in space in the radial direction.

According to the observations of VLF radiation in Kamchatka for the period from 1997 to 2017, radiation envelope periodograms at the frequencies of 0.7, 1.2, 5.3 kHz were obtained. The period of 1440 min was determined. It is caused by the Earth rotation around its axis relatively the Sun. Another period of 1436 min was also distinguished. It coincides with the Earth diurnal rotation relatively remote stars. The cause of the maxima occurrences at these periods may be the X-radiation of the Sun and the Galaxy. It was shown that VLF radiation intensity in the period range from 0.1 to 1000 days increases proportionally to the period logarithm and that the main and higher harmonics of diurnal frequency are observed in the radiation envelope spectra.

Among other things, artificial magnetically oriented irregularities are generated by the experiments on active impact on the ionosphere. They can be used for interlayer ionospheric waveguide excitation. We can suggest that the efficiency of waveguide excitation depends on mutual location of magnetically oriented irregularities and a feed element as well as on their topology in the interlayer ionospheric waveguide. To verify this hypothesis, electromagnetic radiation monitoring was applied in Kamchatka. The radiation was generated by the active impact on the ionosphere in Troms (Norway).

The paper represents experimental studying the scales of turbulent vortices in diffusion flames by using the measurements of thermodynamic characteristics obtained by thermography and the aerodynamic characteristics obtained by the PIV method.

The paper represents experimental studying the pulsations of temperature fields and the structure of a flow in the flame formed during the combustion of certain fuels. Also, the paper provides the mathematical modeling of a flow in the flame formed during the combustion of diesel fuels, as well as the comparison with experimental data and the estimation of the scale for turbulent vortices in flame. The experimental results are in satisfactory agreement with numerical modeling, which confirms the hypothesis of similarity for the pulsations of hydrodynamic and thermodynamic parameters.

The paper presents the results of a study of the backscattering enhancement factor (BSE) dependence of vortex LaguerreGaussian beams propagating on monostatic location paths in the atmosphere on optical turbulence intensity. The numeric simulation split-step method of laser beam propagation was used to obtain BSE factor values of a laser beam propagated on monostatic location path in the turbulent atmosphere and reflected from a diffuse target. It is shown that BSE factor of the averaged intensity of a backscattered vortex laser beam of any topological charge is less than BSE factor values of backscattered Gaussian beam in arbitrary turbulent conditions.

One tool to improve the performance of Monte Carlo methods for numerical simulation of light transport in the Earth’s atmosphere is the parallel technology. A new algorithm oriented to parallel execution on the CUDA-enabled NVIDIA graphics processor is discussed. The efficiency of parallelization is analyzed on the basis of calculating the upward and downward fluxes of solar radiation in both a vertically homogeneous and inhomogeneous models of the atmosphere. The results of testing the new code under various atmospheric conditions including continuous singlelayered and multilayered clouds, and selective molecular absorption are presented. The results of testing the code using video cards with different compute capability are analyzed. It is shown that the changeover of computing from conventional PCs to the architecture of graphics processors gives more than a hundredfold increase in performance and fully reveals the capabilities of the technology used.

Results of experimental and theoretical studies of the process of near-ground propagation of monochromatic acoustic radiation on atmospheric paths from a source to a receiver taking into account the contribution of multiple scattering on fluctuations of atmospheric temperature and wind velocity, refraction of sound on the wind velocity and temperature gradients, and its reflection by the underlying surface for different models of the atmosphere depending the sound frequency, coefficient of reflection from the underlying surface, propagation distance, and source and receiver altitudes are presented. Calculations were performed by the Monte Carlo method using the local estimation algorithm by the computer program developed by the authors. Results of experimental investigations under controllable conditions are compared with theoretical estimates and results of analytical calculations for the Delany–Bazley impedance model. Satisfactory agreement of the data obtained confirms the correctness of the suggested computer program.

Results of experimental studies carried out at the testing ground of the Basic Experimental Complex (BEC) of the V.E. Zuev Institute of Atmospheric Optics SB RAS in 2016 are reported. Statistical characteristics of jitter of video images of remote objects are analyzed. The possibility of estimating the path-integral structure characteristic of the refractive index at atmospheric paths by a passive optical method is demonstrated.

The paper deals with the simulation of such optical phenomena as halos, glories and coronas. To simulate these, we use the Monte Carlo method taking into account the multiple scattering of solar radiation. We have developed visualization software to represent computational results.

The paper presents the results of Monte Carlo simulation of the radiation regime in the system “atmosphere - water layer”. The radiation reflection and refraction at the sea surface is simulated with the help of the Fresnel formulas. The facet model is used to describe the sea surface roughness. The vertical stratification of the actinic flux, radiance and angular distributions of the solar radiation are investigated.