The results of a study of vibrational spectra of volatile hydrides of the VA group elements of periods 2 - 4 in the liquid state and in solutions of liquefied noble gases have been generalized and analyzed over wide frequency and temperature ranges. A number of anomalies have been revealed in the spectra of these hydrides that manifest themselves through an unusual behavior of band intensities of basic, composite vibrations and overtones on a transition from the gas phase to the condensed state, and dependences of spectroscopic and dynamic parameters as well as a non- coincidence of the line maxima in isotropic and anisotropic Raman spectra ((delta) v equals v_aniso-v_iso) on the temperature of liquid hydrides. Mechanisms of intermolecular interactions in these liquids are discussed with the use of the as-obtained data on the intensity, frequency and shape of vibrational band contours.

Based on ab initio calculations by the Hartree-Fock-Roothaan method of the potential energy surface of the complex H₂O...HF, the optimum model (both in the sense of exactness and simplicity) is built to calculate the low-frequency shift (Delta) v of the vibrational band of arbitrary monomer Y when it forms the weakly bonded complex H₂O...Y under the atmosphere conditions. The model uses only parameters of the one-dimensional potential function of the anharmonic oscillator Y in the field of the H₂O molecule; the model is based on the fact that the vibrational variables of the fast and slow subsystems are adiabatically separated in the complexes with the hydrogen bonds.

To increase the efficiency of identifying the complex aromatic compounds, the present paper gives the results of investigating the low-frequency region of the IR absorption and recorded doublet structure of absorption bands of the deformation(al) vibrations of naphtalene-, anthracene-, phenantrene-, pyrene- and coronene molecules in a fine- disperse state in matrices of KBr, polyethylene and in a vaseline oil. Parameters of changing the position of the centers of doublet components and the relationship of their intensities in changing the temperature are determined. Parameters of doublet components in dependence on the concentration of aromatic molecules in KBr tablets are investigated.

In this work were performed calculations of energy of S₀ yields S₁ vertical transition in complexes with hydrogen bonding, which can be formed in atmosphere at the interaction of molecules H₂O with other molecules with hydrogen atom such as, for instance, HCl, being kept an danger ecological components in emissions of industrial enterprises. The equilibrium structures and molecular properties of S₀ and S₁ states of (H₂O)_n(HCl)_m, n, m <EQ 2, complexes were calculated at ab initio SCF, ROHF and CI levels with use of the MONSTERGAUSS program. Analysis of electron density distribution for S₀ and S₁ states was performed. The excitation energies of S₀ yields S₁ transitions (H₂O)_n(HCl)_m, n, m <EQ 2, complexes were determinated. The influence of hydrogen bond formation on the shift in the maximum of first absorption band of these complexes was examined. The investigations of electronic excited states of molecules allow solving some analytical problems. One of them it is a problem about identification of substances. In virtue of data about electronic excited states it is possible to carry out a study of photophysical and photochemical processes what take place after photon absorption. From an analysis of experimental data follow that formation of intermolecular hydrogen bond results in the shifts of absorption bands. The shift depends from type of electronic transition. The investigation of the nonriged molecular complexes is important for atmospheric spectroscopy purposes. Complexes of (H₂O)_n(HCl)_m type are interesting from standpoints also of fundamental spectroscopy. Detailed study of structural nonrigidity effects (particularly for molecular complexes with several types of MLA) stimulates a development of new direction in molecular spectroscopy, weak bonded complexes and ensures a reception new given for the development and revision of number of positions of molecular and chemical physics, theory of reactionary ability, thermodynamics and complex formation and others.

The new analysis of water vapor high resolution spectrum in the 17358 - 21400 cm^-1 region has been performed using conventional scheme of the effective Hamiltonians (EH) as well as recent high accuracy ab initio calculations of line position and intensities by H. Partridge and D. Shwenke [J. Chem. Phys., 106, 4618 (1997)]. About 27% of the observed absorption lines were additionally identified compared to previous study by Carleer et al. [J. Chem. Phys., 111, 2444 (1999)].

Chemically active or toxic molecules of the man-made origin, such as hydrogen halides, fluorides, chlorides, hydrides, oxides, etc., interact easily with the basic molecular gases of atmosphere and, first and foremost, with water, whose content in atmosphere at small altitudes is from 0.02 to 4% mass. In addition to the products of chemical reactions, the feasibility of which is high only for particles present in relatively high concentrations, there is a high probability of the formation of molecular complexes with the energy from several tens of calories up to several kilocalories in atmosphere. The optical activity of such complexes may be fairly large. Therefore these compounds may become a source of additional radiation losses in atmosphere of industrial regions (for example, with developed radiochemical, chemical and electronic industries, metal manufacture, etc.) and of a disbalance of solar radiation fluxes. Gas-phase complexes are, as a rule, characterized by several kinds of motions of large amplitude, which bring out a transformation of vibrational spectra of their constituents (the spectral shift in respect to free molecules can reach several tens cm^-1) and an appearance of new bands corresponding to intermolecular vibrations. The indicated factors, in their turn, result in serious methodological difficulties in detection and evaluation of the concentration of molecular complexes in atmosphere with the application of the state-of-the-art remote laser sounding technique.

The present study focuses on the weak H-bonded (H₂O)_n(HCl)_m complexes. One of the most recent trends in vibrational spectroscopy has been directed towards intermolecular interactions and motions. A range of spectroscopic techniques including molecular beam electric resonance, pulsed-nozzle Fourier transform microwave, and infrared laser are capable of providing valuable information concerning the structure and properties of a large number of H-bonded complexes. The intermolecular modes can be studied directly by far infrared, low-frequency Raman, and incoherent inelastic neutron scattering spectroscopy. However, the low concentrations of these complexes and interference from the very intense rotational spectra are occurring in the far-IR regions makes reliable interpretation of the spectra of molecular complexes very difficult task. A complete set of intermolecular vibrations has been determinated for only a very limited number of H-complexes. The quantum mechanical ab initio calculations can be of great use in assisting experimentalists with band identifications and elucidation of general principles. Structure, energetics, and vibrational spectrum of row of (H₂O)_n(HCl)_m complexes were studied in this work. Ab initio calculations were carried out using 6 - 31 G** basis set containing polarization functions on all atoms. Complete optimization of the geometry was performed at the RHF level with the gradient procedures and Newton-Raphson method. The basis set superposition error (BSSE) was calculated. The vibrational analysis was done.

In the paper the conception of Pade-approximants in the framework of broadening theory of spectral lines was presented as an example of the generation of effective polarizability operators in excited vibrational states of three atomic quasi- rigid molecules. This conception is a part of the theory of linked ordering schemes of intra- and intermolecular interactions in polyatomic molecules. In the framework of the theory of linked ordering schemes in the limited ordering scheme corresponding to super excited oscillator model the vibrational dependence of mean polarizability for H₂O molecule in the form of Taylor series on the power of vibrational quantum numbers is proved. Taylor series was summed up using Pade-approximants technique.

The numerical evaluation of higher order centrifugal distortion electrodipole moments of methane on the base of ab initio calculations of electro-optical parameters obtained earlier is presented for the first time. The behavior of these moments at the high values of full angular momentum quantum numbers is analyzed with marking use of Pade approximant method.

The cybernetic methods are used for data processing in vibration-rotation spectroscopy, automatic line search and determination of spectroscopic parameters in 'large' spectra containing thousands of lines. The developed computer-aided system uses the pattern recognition (the potential function method), cluster analysis and non-linear least-squares fit. These techniques in combination with various statistical procedures allow one to perform automatic spectra analysis that represent to a user possibilities weren't available before. The searching procedure based on the pattern recognition technique provides good line detection and noise separation. The fitting procedure has regularization component that brings more robust spectra processing. The output file contains: frequency, intensity, half-width for each line and an error estimation of line position. The present results may be interested for computer specialists interested in the problems of pattern recognition and developments of the expert and instrumental information systems for molecular spectroscopy.

Within the framework of the linked ordering schemes theory of vibration-rotational interactions in molecules the introduction of Herman-Wallis factors into intensities of multiquantum vibrational transitions has been presented in effective dipole moment operator by sequences of types M_eff equals M_n1 + M_n2 + M_n3 + ..., where n equals 1, 2, 3, ... . The results of group-theoretical analysis of tensorial parameters in M_1n (n equals 1 divided by 3) for symmetric top molecules have been presented. Generalization of these results for multiquantum vibrational transitions is analyzed. The another goal of the contribution was the analysis of the ways of the construction of nonpolynomial models for Herman-Wallis factors on the base of the representation of M_eff in forms of infinite sequences on angular momentum operators. Some simple models for HW factors in Pade-approximant form are considered. On the base of developed and presented theory of vibration rotation line intensities in molecular spectra the conception of fitting molecular dipole moment transition of quasirigid molecules is discussed for the first time.

To solve the problem, connected with wide-band light fluxes transfer through multi-component scattering medium like the Earth's atmosphere, an extensive information on optical properties and, in particular, absorption spectra of its components is required, as well as a development of efficient methods taking into account the molecular absorption in solving the transfer equations. To eliminate the limitations imposed by model interpretation of absorption bands, the 'k- distribution' method is gathering force in recent years, which offers a convenient parameterization of the absorption functions in the form of exponential series. This method gives the calculation accuracy comparable with that obtained by the direct method. In this work, the 'k-distribution' method is applied to the case of overlapping the absorption bands in some inhomogeneous medium. The test calculations of short-wave radiation fluxes were conducted by this method both regarding for the molecular and aerosol scattering and ignoring it. The obtained results well agree with those obtained by the direct 'line-by-line' method.

This paper generalizes the results of development of few- parameter models of transmittance, which provide both the needed accuracy close to that given by the LBL method and the high computational speed. Particular emphasis is placed on the latest advances connected with the Laplace transformation and presentation of the transmission function as exponential series.

The total energetic exposition on a horizontal surface at the top of the atmosphere in different seasons of a year at the latitude of 30 to 45 degrees is estimating. Cloudiness decreases the direct solar radiation on a horizontal surface by 10 - 15% (upper clouds level), by 20 - 25% (middle clouds level) and by 30 - 35% (lover clouds level). In Central Asian region the direct solar radiation flux decreases with increase latitude by 37% (winter), by 25% (autumn) and by 10% (spring). In summer season the direct solar radiation flux increase in June ((phi) equals 43 degrees), July ((phi) equals 39 degrees) and August ((phi) equals 37 degrees). The equation composition of the radiation balance from varies cloud forms and transparence atmosphere in the wavelength range 0.38 to 0.71 micrometer on latitude 40 - 41 degrees is given. The hard aerosol pollution decreases the direct solar radiation by 10 - 15%.

Some peculiarities of the femtosecond laser radiation propagation through molecular resonant media are studied. Calculations of atmospheric transmission through the horizontal paths are also presented.

In this paper we present some results of monitoring the total solar radiation, which is being performed at the TOR-station of IAO SB RAS since April 1995. Some results of evaluation of the radiation regime nearby Tomsk have been verified by the comparison with the actinometric data of Ogurtsovo station. We have revealed that during the period of the study quite steady radiation regime with maximum of incoming solar radiation in July was observed. The amount and variation range of the monthly mean solar radiation varied depending on the season. During wintertime the coefficient of variation of the monthly mean radiation varied within 5 to 9% and from 2 to 24% during transition periods. The amount of solar radiation income depending on air mass type and synoptic condition has been investigated. It is noted that the amount of diurnal solar radiation in winter season does not depend on the type of pressure field and air mass. During other periods diurnal solar radiation sums are larger at the presence of anticyclones.

Method of light-wave measurement for adaptive optical systems, which may be useful in conditions of the strong fluctuations, is considered. It is proposed to measure the light-wave phase on a closed trajectory, lying into the aperture where the wave intensity is significant, and to locate boundaries of the probably optical vortices, within which the intensity is close to zero. Operations and schematics of two novel devices are described, namely Hartmann Scanning Sensor and Directional Shearing Interferometer.

We introduce the image functionals used in the adaptive optical systems of aperture sounding and estimating the wave front modes which can be corrected by these systems.

On the base of the mathematical apparatus for the two- dimensional normalized cubic smoothing B-splines the wave- front reconstruction algorithm for the optic emission capable of processing efficiently the nonstationary distortion with the noise in the control channels has been synthesized. The analytical expression for the selection the elements of the Gartman-type sensor optimal in terms of providing the prescribed precision of the wavefront reconstruction has been obtained. Is conducted of the efficiency analysis of operation of the synthesized algorithm in the presence of the different intensity of noises in the control channels of the adaptive optical system.

With the use of the methods of numeric simulation the possibility is analyzed of adaptive correction for randomly inhomogeneous layer of a turbulent atmosphere on the base of phase conjugation. The atmosphere was simulated as a set of random screens. The influence of different parts of distributed lens on distortions of a laser beam is considered as well as efficiency of corrections for screens placed on various distances from the transmitting aperture. It was shown that the most severe distortions were induced by turbulent layers located on the maximum distance from the plane of observation. At the same time correction for these layers is the most efficient.

Propagation of laser beam in a turbulent atmosphere, at which are present resonance absorbing impurities, is featured by the parabolic equation of a quasi-optics. The spatial distribution of an impurity is nonuniform, fluctuation of its concentration, as well as fluctuation of density of a pure atmosphere, influences on structural function of an inductivity fluctuations. The analysis of propagation of laser beams will be carried out with the help of the equation for the moments of amplitudes of a field obtained from the parabolic equation with a random function by an inductivity of medium with allowance for of influence of impurities.

In this paper we consider the results of experimental investigations of the variance, time frequency spectrum, time autocorrelation function and the probability density of laser radiation fluctuations in snow fall in a narrow divergent laser beam along the paths from 14 to 2048 m long and describes the fluctuation characteristics in snowfall and some of the characteristics are compared with those propagating at fine weather (without precipitation).

We develop an algorithm of the wave front mode correction by the image in the adaptive optical system based on the Newton modified method. We show that the image control by the wave- front phase predistortions being checked makes the method invariant not only to the incoherent radiation source but in the first approximation to the wave amplitude forming the image. The consideration of the entire spatial spectrum of images in calculating the derivative matrix increases the method convergence. We present the results of numerical simulation of the segmented mirror phasing and alignment correction and the Zernike mode correction for a flexible mirror.

Spatial dynamics of distortions of the of the laser beam wavefront under the conditions of forming and evolution of the optical vortices have been study, energy streamlines have been constructed, and regularities of appearing the wave-front dislocations have been revealed. The system of differential equations for the energy streamlines (rays) in the three- dimensional space derived based on the parabolic equation for the complex amplitude of the monochromatic wave field was solved by the Euler technique with an automatic step choice. An analysis of the structure of the Umov-Poynting vector field for the different longitudinal coordinates in combination with the solution of the equation system allowed the rays spatial dynamics to be investigated. It was established that the rays were focused in the vicinities of the points corresponding to the nodes of the Umov-Poynting vector field for the beam having first the smooth wavefront. Such an energy distribution in the space stimulated appearing the points with zero intensity in the plane transversal to the propagation direction, the pairs of optical vortices were born in these points (bifurcation 'nodes - focuses'). Rays trajectories gained the spiral form in the vicinities of arising dislocations. In the process of the beam propagation the vortices first diverged and then drew together and annihilated, the wave-front was transformed from the singular to the smooth one, the rays stopped to twist and then focused as far as the next branch point. The initial point configuration determined the further ray trajectories and vortex evolution.

The statistics of high altitude wind speed data at the tropopause (200mB) above Mt. Maidanak in Uzbekistan are presented. These data were obtained in 1991 at three meteorological stations Kokand, Tashkent and Termez, located around Mt. Maidanak. The data processing show that the high altitude wind speed above Mt. Maidanak is slowly changed with predominant direction from the west. The average value of wind speed at 200 mB for the entire period of observations is 27.0 m/c. The comparison of results with data, obtained at Paranal observatory in Chile shows, that this parameter of atmosphere at Mt. Maidanak is comparably small than above Paranal.

The vibrations of droplet surface results in origin of a dynamic component of scattered light. These vibrations arise or by virtue of natural reasons connected with a movement of particles in the atmosphere, or can be stimulated by modulated light radiation. The vibration frequencies of droplets are unequivocally determined by their sizes and properties of a liquid, that gives an opportunity of reception of the quantitative information about size distribution, proceeding from frequency behavior of a dynamic light scattering component. The resonant stimulation of droplets vibration causes increase of dynamic light scattering component amplitude. Besides, use of the modulated radiation results in synchronizing of droplets vibrations, that leads to the best detecting of a dynamic light scattering component in comparison with spontaneous vibrations of drops. The numerical modeling of dynamic light scattering on stimulated ponderomotive vibrations of polydispersed aerosol droplets is carried out. The direct task is solved and is shown, that frequency behavior of intensity of light scattering is sensitive to the changes of an initial size distribution. The solution of inverse problem allows us to restore particle size distribution with satisfactory accuracy. The analysis of solution stability has shown, that for droplets sizes lager 1 micrometer the restored size distribution is stable to small mistakes in frequency behavior of scattered light intensity.

The paper is devoted to the problem of derivation of optimum conditions for the development of stimulated light scattering (SLS) processes in spherical micron-sized particles. The equation for threshold pumping intensity in the case of realization in a particle the conditions of a double SLS resonance for incident and scattered waves was obtained. The coefficient of spatial field overlapping B_c((omega) _L, (omega) _S) was introduced. The coefficient B_c((omega) _L, (omega) _S) is shown to be approximately one order of magnitude higher when the mode order of input and output resonances are equal, then when they are different. The main factor determining the value of B_c((omega) _L, (omega) _S) is the FWHM of excited modes.

The results of experimental investigations of temporal characteristics of an acoustic pulse formed at various regimes of thermal interaction between CO₂-laser high-power pulses and small volumes of an absorbing liquid are submitted. A connection between the shape of the generated pressure pulse and regimes of laser radiation interaction with a substance is established. The model of pulsing sphere is applied to interpretation of the received dependence of characteristics under study on the laser energy density. The comparison of computed and experimental data is carried out. The results of measurements of the acoustic response are submitted with propagation of a laser pulse on an atmospheric path. The opportunity of use of an acoustic method for search of laws is discussed with formation in an atmosphere of a long laser spark.

The thermocapillary mechanism of nonlinearity of two-component medium (aerosol, mocroemulsion) is investigated, in which case the drift of particles in temperature field is due to the temperature dependence of the surface tension coefficient of the phase interface. Redistribution of particles concentration therewith changes the local index of refraction (absorption) of the medium, providing in such a way the presence of nonzero coefficient of efficient cubic nonlinearity. In terms of linear nonequilibrium thermodynamics, the variation of dielectric permeability of two-component medium exposed to action of incident radiation is caused by two fluxes: thermal J_T and concentration J_C, which in general case are thermodynamically mixed and are determined by kinetic coefficients L_ij. In the case of weakly absorbing medium, the expression is obtained for the efficient coefficient of cubic nonlinearity. The experimental investigation of the thermocapillary nonlinearity was conducted in the bubble medium in two regimes: at laser radiation self-action and dynamic hologram recording. The generated hologram was of amplitude-phase character, but due to relatively large size of bubbles, the grid of the extinction coefficient was prevailing.

The propagation problem of the partially coherent radiation in inhomogeneous media is investigated in this paper. The error of the ray-tracing technique for solving the equation for coherence function of the second order is estimated. The ray- tracing technique is asymptotically exact since it gives the exact solution in following limiting cases: within the limit of the geometrical optics ((lambda) yields 0), when the coherence length tends to zero, or when the distribution of the medium complex dielectric permeability has a parabolic form. To estimate an error of the ray-tracing technique for both coherence length and wave length not equal to zero and for an arbitrary distribution of the dielectric permeability the comparison of solutions obtained by the ray-tracing technique with exact ones is performed. The exact solutions are obtained for a model propagation problem of a two-dimensional slit beam for which the dimensionality of the equation decreases from five up to three. To solve the coherence function equation the exact splitting method is used in a combination with the fast Fourier transform. It was obtained that the relative error of the power and statistical characteristics calculating by the ray-tracing technique is no more than 15% at worst. For the majority of problems having practical meaning the relative error of the ray-tracing technique does not exceed 3 - 5%.

Generation of acoustic radiation by local plasma formations initiated by solid aerosol particles is one of the nonlinear effects of interaction between high-power laser radiation and atmospheric aerosols. In the present report, time histories of acoustic pulses radiated by discrete plasma formations, initiated under the action of focused laser radiation on a single solid aerosol particle suspended in the laser beam caustic region or on an ensemble of solid monodisperse aerosol particles injected in the laser beam caustic region, are analyzed. The measurements have shown that each local plasma formation radiates a single spherical acoustic pulse, and the total acoustic signal represents a linear superposition of pulses from separate plasma formations. The shape of a single acoustic pulse is satisfactorily approximated by a sinusoid for particles of micron sizes and reproduces a blast N-wave for particles with sizes varying from several tens to several hundreds of micrometers. The average amplitudes and half- periods of acoustic pulses depend linearly on the effective particle diameters with the proportionality coefficients determined by the particle material. The inequality of amplitudes and durations of positive and negative half-periods of acoustic pulses radiated by local plasma formations was also found.

The results of statistical analysis of the spectra of acoustic signals radiated by local plasma formations initiated on single 400-micrometer SiO₂ and 170-micrometer SiCO₂ particles and on an ensemble of 7- and 28-micrometer monodisperse SiC particles upon exposure to radiation from a pulsed GOS-1001 laser with a wavelength of 1.06 micrometer are presented. A clearly pronounced wide maximum is typical of the spectra of acoustic pulse radiated by a plasma formation initiated on a single solid aerosol particle. The frequency of this maximum is shown to be dependent on the duration and shape of the radiated sound pulse. The total acoustic signal radiated by discrete plasma formations initiated on an ensemble of monodisperse particles injected in the laser beam caustic region represents a linear superposition of pulses from separate plasma formations. Its spectrum also has a wide maximum, whose amplitude and halfwidth are determined by the number of local plasma formations and the rms amplitude of acoustic pulses from separate plasma formations. The frequency of this maximum is shown to be dependent on durations and shapes of pulses from separate plasma formations.

In lidar remote sensing the classical lidar equation is normally used for the retrieval of environmental parameters from the return signal. One of the most important reasons for this is the simplicity of this equation which describes the contribution of single scattering to the return signal only. But it is well known that multiple scattering occurs in lidar sensing of dense clouds and remote cirrus clouds. Therefore a more and more precise description of lidar returns is needed. We present a stochastic model for the description of the transport of light through the atmosphere and obtain an exact multiple scattering lidar equation from which by introducing simplifying assumptions step by step the classical lidar equation may be derived. Of course, more information about the scattering behavior of the scattering particles or molecules of the atmosphere is needed for such an exact multiple scattering equation, but the more input is necessary the more output is possible. Indeed, it is possible to obtain simultaneously quite different environmental parameters (e.g. extinction and size distribution) from one multiply scattered return signal. We show examples of simulations of returns of a ground-based and a spaceborne lidar from water clouds, cirrus, and haze. These simulations and the obtained importance of the contributions of higher orders of scattering show the need for a more precise modeling of lidar returns, especially for spaceborne lidars.

The present paper considers a set of problems of statistical modeling for the transport of solar radiation in stochastic natural media as applied to the problems of remote sensing of the ocean and aerosol and cloudy atmosphere as well as to the problems of constructing the numerical models of solar radiation fields in clouds and cloudy atmosphere. The basis of this consideration is the statistical approach when the radiation transfer is described by the equation, in which some of the parameters are random functions. A set of new Monte Carlo algorithms and programs has been provided for the purpose. This set includes algorithms for the simulation of homogeneous stationary random fields of continuous and broken cloudiness, the optic parameters of the atmosphere and the ruffled sea surface as well as the simulating the radiation transfer process in stochastic media. A special attention has been paid to solving the problem of optimization of Monte Carlo algorithms.

Of decisive importance in diagnosing the ionospheric channel is the use of vertical-incidence sounding (VS) ionograms. The ionogram processing problem involves identifying characteristic points corresponding to actual signal modes, followed by approximating them in the form of traces. Within the framework of this problem, it is necessary to take the following steps: (1) to carry out a preprocessing of ionograms; (2) a compression of the data resulting in a substantial reduction in their amount and the identification of the times of arrival of the signal; and (3) a combination of the points, thus identified, into traces and referencing them to particular propagation modes. The solution of the first problem is achieved through use of statistical techniques for processing images. The cellular automaton is proposed in order to solve the second problem. The third problem is tackled by implementing Hopfield's method of artificial neural networks. As a consequence of the complicated character of the VS ionograms and due to the presence of scattered signals, errors are possible both when determining the times of arrival of signals and, especially, when combining them into traces. To solve this problem we suggest that use should be made of predicted values of critical values (foE, foF2) and heights h'F of regular layers obtained from a real-time version of the ionospheric model. An analysis of results made on the basis of the data from the ISTP chirp-sonde (Irkutsk) showed that this approach yields good results.

The lidar equation with consideration of multiple scattering in the small-angle approximation is analyzed in the present work. To describe a lidar signal, a model of the scattering phase function represented by the sum of diffraction and geometric-optics components is used. A method for separating the diffraction and geometric-optics lidar signal components is suggested. It is shown that for large field-of-view angles of the receiver, this allows the diffraction component of the scattering phase function to be replaced by one parameter -- the effective radius of particles.

Separation capability of singly and multiply scattered components in a lidar receiving system based on the use of spatial filtering of lidar returns is considered. A calculation example for a return power density is shown. A procedure for determination of a multiple scattering spot parameter is described. Experimental results of sounding the clouds are presented. Various instrumental realizations of the spatial filters for the practical use in elastic scattering lidars are discussed.

The atmospheric correction procedures for space imagery is implied to be in evolving the subsequent approaches in direct problems of atmospheric optics along with finding ways to solve the inverse problems. The direct problems are in using any approximation of the radiation transfer theory to calculate the outgoing radiation field at the top of the atmosphere level with any selected boundary conditions. The inverse problem includes a particular form of the retrieval of parameters characterizing the state of the land cover patterns. Pattern recognition and scene analysis techniques are adjusted to the atmospheric correction procedures for a particular state of the atmosphere for the data of remote sensing surveying the land cover of the region under consideration. The atmospheric optical depth and other characteristics of the atmosphere during the dates of the field campaign are initial to solve the inverse problems using the appropriate radiation transfer improvements.

The problem of early detection of small-sized fires is very urgent, especially for almost inaccessible and sparsely populated territories. In this connection, a necessity arises of using satellite information to solve problems of real-time detecting sources of thermal anomalies suspicious of a fire. Among the Earth's artificial satellites most frequently orbited above a given locality that allow problems of monitoring of the Earth's underlying surface (EUS) to be solved, it is natural to choose satellites of NOAA series and to use the data of the AVHRR instrument that records radiobrightness values in five spectral ranges, including thermal ones, in the form of images. Unfortunately, low resolution of the AVHRR instrument and comparatively narrow range of radiobrightness values registered with it do not allow the problem of early detection of small-sized fires to be solved efficiently by conventional methods. Let us consider an approach based on theoretical methods of statistical hypothesis testing (pattern recognition) used for solving problems with high degree of statistical uncertainty and unknown conditional probability density functions. Probabilistic models of situations to be recognized, one of which belongs to class 'Fires' and the remaining belong to 'Fire-like' interference classes, are reconstructed in spaces of the parameters informative for the minimum risk criterion. The detection of fires based only on the temperature does not allow this problem to be solved efficiently. Let us assume that examined images have already been preprocessed: geometrical distortions have been eliminated from videodata, they have been fixed geographically, their fragment with the territory of the Tomsk Region (TR) and its environs has been cut out, and the radiobrightness correction and calibration of videodata recorded with the AVHRR instrument have been performed with determination of albedos in channels 1 and 2 and thermodynamic temperatures in channels 3, 4, and 5. Thus, we have a matrix of 1024 X 1024 five-dimensional vectors to be analyzed.

Wide availability of videodata recorded with the AVHRR instrument used onboard NOAA satellites and frequent recurrence of images of examined fragments of the Earth's surface stimulate attempts at solving problems of resource- ecological monitoring based on these data. Unfortunately, poor spatial resolution and significant distortions of geometrical and radiobrightness characteristics of these images make their analysis by algorithms of thematic processing difficult. Because resource-ecological monitoring includes first of all temporal analysis of adjusted videodata, a problem of automatic mutual superimposition of images of an examined region arises, because these image are recorded from different turns of the satellite orbit. In its turn, this problem raises a problem of obtaining equal resolutions of images. An integrated image correction procedure includes the normalization of illumination of images of the Earth's underlying surface recorded in the daytime with consideration of the solar zenith angle and the calibration of video data with the determination of the albedo (in channels 1 and 2) and thermodynamic temperatures (in channels 3, 4, and 5). The elimination of geometrical distortions takes into account variations in the projection of a scanning spot of the AVHRR instrument on a cylinder and includes the recalculation of radiobrightness for a fixed spot diameter. Cartographic fixing of the data and mutual adjustment of images recorded from different turns of the satellite orbit are carried out by minimization of a quadratic criterion of the discrepancy of contour gradients of these images. The integrated image correction allows ensembles of images affixed to the coordinates to be accumulated and their temporal variations to be analyzed to detect forest fires in real time and to forecast the weather against the background of natural phenological changes in portraits of the Earth's underlying surface (EUS).

The development of IR sensors with better spatial, temporal and thermal resolution pushes the necessity to revise and quantify the different atmospheric effects on sensor performance. In this paper, a high resolution IR sensor for point target detection is used as an example to show theoretically and experimentally the relevant atmospheric limitations. Special emphasis is put on the signal-to-noise ratio of point like objects in IR image sequences, on track evaluation of such objects, on the impact of optical turbulence, polarization and refraction in the track analysis.

In the paper it is proposed to make a spatial-time analysis of aerosol micro pulse lidar data by a parametric statistical approach based on a mixed model of 'auto-regressive-moving average' (ARMA). The given approach allows obtain the spectral estimations of auto- and cross-spectra with high frequency resolution using short time series of data. The determination of parameters of the ARMA model has been made on a scheme of two-channel spectral estimation by the Nuttall-Strand method. The examples of obtaining an additional information data on dynamics of aerosol inhomogeneities from real micro pulse lidar are presented.

Based on the method suggested by the author, the data of acoustic sounding with the Zvuk-2 three-channel Doppler sodar with operating frequency 1700 Hz capable of measuring the backscattered signal power are interpreted. A closed iterative algorithm considers the excess turbulent attenuation of a sodar pulse when it propagates along the path from the transmitter to the sounded volume and back to the receiver. Synchronous vertical profiles of the thermal C_T²(z) and velocity C_V²(z) structure parameters are obtained for altitudes up to 515 m. Cases of synchronous altitude behavior of C_T² and C_V² were observed along with cases where the minimum in the C_V² profile corresponded to the maximum in the C_T² profile. Simultaneous measurements show that the main contribution to the refractive index structure parameter C_n²(z) and hence to the turbulent sound attenuation in the above-indicted altitude range comes from the dynamic turbulence. Altitude behavior of the sound refractive index structure parameter and the turbulent energy dissipation rate are discussed.

The algorithms for determining the first four moments, their standard deviations, asymmetry and excess coefficients of wind velocity components (radial V_r and orthogonal V_ort components, absolute value of the horizontal wind V_h and its direction (phi) ) by the Volna-3 sodar are described. The quality of estimation of these moments heavily depends on the quality of sodar measurements of instantaneous radial components V_r(i) and the accuracy of determination of their centers of distribution. So, to reject possible anomalous values, the corresponding procedure of iteration censorship of data is applied to V_r(i) with the further use of the adaptive averaging procedure. For the V_ort, V_h, and (phi) two methods of estimation are considered. The first method is based on calculation of their instantaneous values, and the further processing of V_ort and V_h components is similar to that of the radial components V_r. The moments of (phi) are obtained using statistical methods. The second method is based on the use of pre-calculated moments of V_r and their additional statistical characteristics. To objectively estimate the degree of certainty of the obtained information, the point (standard errors) and interval (90% confidence intervals) estimates of random measurement errors are calculated.

The automatic IR hygrometer of turbulent micropulsings of absolute humidity is developed and is tested in nature conditions. The results of a series of experiments with use of this meter, and three-component sonic anemometer-thermometer are reported in this paper. The synchronous time series of fluctuations of absolute humidity, temperature and components of wind velocity are obtained. The vertical eddy fluxes of the water vapor, sensible and latent heat are calculated. The cross-correlation function, and auto-spectra of wind velocity components, humidity and temperature fluctuations are considered.

The field of applicability of high-frequency acoustic radars and the design of the mS-1 minisodar developed at the IOM of the SB RAS are described. The first preliminary results of minisodar tests are presented.

The paper discusses the method, possible errors, and results of retrieval of altitudinal-temporal distribution of normalized structure characteristic of temperature fluctuations in the atmospheric boundary layer from measurements by VOLNA-3 sodar owned by Institute of Atmospheric Optics SB RAS.

For the purpose of remote sensing in microwave the experimental studies on dielectric properties of wet soils and grounds in microwave and effect of bound water on their dielectric properties are conducted. The applicability of empirical refractive model for description of complex dielectric constant of soils containing bound water is examined for temperatures above and below 0 degrees Celsius. A possibility to detect the point of transition from bound water predominance to free water is demonstrated. The principle of creation a database on dielectric properties of soils with the aim of interpretation remote radiometric measurements is proposed. Some results of field researchers on the test sites of Altai region are considered.

It is known, lidar signal intensity due to double scattering depends on the particle size distribution of under investigation aerosol formation. The most sensitive to microstructure of sounding aerosol is lidar signal component, which is defined by diffraction component of the phase function. Analytical expressions for return scattering radiation received from aerosol cloud at different distances are analyzed in this report. Also possible methods of extraction from lidar signal sensitive to microstructure sounding aerosol component are considered. Theoretical analysis results are reported.

Backscattering of light by hexagonal ice columns and plates has been calculated by means of a ray-tracing code. It is shown that backscattering by the hexagonal ice cylinders at their arbitrary orientations is caused by a peculiar corner- reflector effect. The backscattered wave consists of a number of plane-parallel beams that do not intersect in the near zone of the particles.

We present here some results of the study of vertical profiles of aerosol scattering coefficient, and vertical profiles of wind velocity and wind direction in the boundary layer over Lake Baikal based on analysis of the data array compiled during whole day round lidar observations carried out in the summer field missions of 1998 - 1999. It was noticed in this study that the aerosol fields over Lake Baikal are characterized by a much complicated vertical structure that, in its turn, is caused by specific features of the air mass circulation in the mountain valley of the Lake Baikal. The estimates of the vertical size of the air circulation cells showed that the lower boundary of the cells is at about 300-m height, while their top being normally at a height from 1000 to 1300 m.

According to data of space observations, the aerosol scattering parameters in the Earth's upper atmosphere obtained by the method of tangent sensing in ultraviolet wavelength range (273, 280 nm) with the help of the astrophysical space station Astron are presented. The inverse problem of remote sensing was solved taking into account vertical smoothing effects for altitude dependence of the atmospheric spectral brightness observed in the Earth's limb. High turbidity is observed under unperturbed atmospheric conditions at altitudes near 50 km and between 65 and 100 km. Splitting of aerosol layers at altitudes near 80 and 93 km when instrumental smoothing effect is taken into account is rather obvious. It is established that after Space Shuttle launches a long-lived and extended aerosol layer is formed along the active trajectory of launch at altitudes near 100 km. The characteristic transverse size of anthropogenic layer zone is about 900 km, though the perturbation is observed up to 1500 km.

A transportable scanning multiwavelength lidar has been installed for the independent and simultaneous determination of the particle backscatter coefficient at 6 wavelengths between 355 and 1064 nm and of the particle extinction coefficient at 355 and 532 nm. The physical particle parameters including the complex refractive index are retrieved from the optical data by an inversion scheme based on the Tikhonov's regularization technique. The optical and physical parameter sets serve as input in radiative transfer calculations to estimate the radiative forcing of the particles at the top of the atmosphere and at the surface. Quite different particle properties could be observed during the Aerosol Characterization Experiment (Portugal, 1997), the Lindenberger Aerosol Experiment (Germany, 1998) and the Indian Ocean Experiment (Maldives, 1999-2000). We present measurement examples which demonstrates this approach of comprehensive aerosol characterization.

The outcomes of numerical simulation of echo-location and ethylene sounding ranges in the atmosphere by differential absorption lidar based on TEA CO₂ lasers are submitted. Is established, that the lidar echo-location range has close to logarithmic function of energy and peak power of sounding pulses. The echo-location range of IR lidar based on TEA CO₂ lasers differs insignificantly on strong and weak emission lines of the laser, that allows to produce the effective sounding of the atmosphere in all range of wavelength tuning of TEA CO₂ laser radiation without correction of pulse energy on various emission lines. Is shown, that the application of narrow-band spectral filters is justified at use of low-noise detectors and receiver FOV angles more than 5 mrad. The evaluations of a relative errors of ethylene concentration measurement in the atmosphere in various modes of registration are conducted.

This paper is devoted to the study of the possibilities of using reflected signal distortion characteristics in diagnosing the propagation medium. In vertical-incidence ionospheric soundings in the high-frequency range, the derivative of the reflectance modulus is one of the measured characteristics of distortions. The paper demonstrates the possibility of using this characteristic to separate the situations of scattering from small-scale irregularities and interference of signals caused by large-scale ionospheric irregularities.

Some of the double channel scanning radiometer Termoscan panoramas were interpreted as those arising in the presence of the aerosol layer containing ice particles in the Mars atmosphere. The radiation fluxes registered by the radiometer where the effect of the Mars surface is omitted shows that the ratio of radiation fluxes at scattering angle (Theta) equals 177 degrees and (Theta) equals 179.5 degrees for different regions in the Mars atmosphere is rather stable and is of the order of 1.08 - 1.14. The models of aerosol medium microstructure in the form of a polydisperse distribution of spherical particles as well as the form of systems of nonspherical particles of cubic and hexagonal forms of equal size (the hexagonal prism length is equal to its diameter) with a chaotic orientation in space have been used. The range of the theoretical ratio of radiation fluxes for spherical particles (0.7 < r₃₂ < 0.9 micrometer), where r₃₂ is the ratio of the third moment of the particle size distribution to its second moment, corresponds to the fluxes ratio range above-mentioned. For nonspherical particles equal in size with the same values of r₃₂ as for spherical particles the values of r₃₂ appear somewhat smaller (approximately 15%) than for spheres.

Estimations are carried out on creation possibilities of all solid state laser sources capable significantly or fully to solve the problem of the universal Aerosol-Gas Lidar System design. 'Best existing Ho²⁺:ILF and Nd:YAG lasers supplied with LBO, KTA, KTP, BBO, CLBO, DLAP; GaSe, GaSe:In, AgGa_xIn_1-xSe₂, LiInS₂, LiInSe₂, AgGaS₂, AgGa_xIn_1-xS₂, and HgGa₂S₄ frequency converters are considered. The investigation results show development of UV to FIR laser source is really to carry out with efficiencies from one-two up to several tens pro cents in several ways.

On the basis of the mapping ozone spectrometer TOMS and the radiometer SSM/I data the results of analysis of the total ozone field perturbations by tropical cyclones in 1998 in the Atlantic active cyclogenesis area are given. The ozone field perturbations were determined as deviations from the long-term average value of total ozone. It is shown that a negative total ozone anomaly at the stages of a tropical storm and a hurricane can reach tens of Dobson units and its spatial size -- several hundreds of kilometers. The ozone anomaly characteristics depend on a tropical cyclone intensity and a storm wind zone dimension. The physical reasons of the peculiarities mentioned are considered.

The results are given of the parallel measurements of water vapor, methane and carbon oxide in the atmosphere of St. Petersburg (Petrodvorets), Zvenigorod and Obninsk in July- August 1999. The measurement data obtained at the three sites made it possible to represent the spatiotemporal variability of the contents of each of the atmospheric gases studied for the European territory of Russia (ETR) in the form of the chart 'latitude-day-content' with the use of the splines of mean daily contents. The dependence of the gases variability on synoptic conditions over the ETR was determined.

Using the Fourier-transform spectroscopy a method was developed for measuring background concentrations of methane (CH₄), carbon dioxide (CO₂), carbon monoxide (CO) and dinitrogen monoxide (N₂O) in air samples taken over the ground. Measurement results are given for CO, CO₂, CH₄ and N₂O concentrations obtained since January 1998 in air samples at Obninsk.

At Scientific and Production Association 'Typhoon' a complex of spectrometers intended for atmospheric ozone measurements from satellite 'Meteor' was designed. The complex consists of two instruments: BUFS-3 and BUFS-4. On-board ultraviolet spectrometer BUFS-3 with the direction of view in the nadir is intended for measurements of total ozone in the atmospheric column (TO), vertical ozone profiles in the atmosphere (VO), as well as the pressure at the height of underlying surface [the height of clouds upper level (UC)]. On-board ultraviolet spectrometer BUFS-4 with the scan of field of view within the range of +/- 52.5 degrees is intended for mapping TO and UC. The development of BUFS-3/BUFS-4 was conducted on the base of analysis of practical work on orbit both of our previous instruments BUFS-1 and BUFS-2 and a similar USA complex SBUV/TOMS. The main differences of BUFS-3 and BUFS-4 from predecessors: the presence of channels for UC measurements, a simple optical scheme, advanced algorithm of measurements, an advanced system of instruments calibration on orbit.

The task of investigation of distribution in upper ocean waters of light absorbing and light scattering admixtures is of great interest for oceanology and, specifically, for appreciation of ecological state of sea waters and their contamination of human matters, first of all, by oil products. Among different measuring methods there are especially perspective ones -- methods of sea laser probing from ship's side without stopping of the ship, which allow to make 'simultaneous measures' in quite different voyages -- tourist, cargo, research cruises and etc. Measures (which did not request stopping of the ship), accompanied by taking of probes during motion for subsequent laboratory analyses were organized in the 53 cruise of R/V 'Akademik Kurchatov' around European continent (1994). The works of such type were executed also in the 26 cruise of R/V 'Vityaz' in Atlantic ocean (1991).

Using data obtained in Canarian Upwelling, Black and Marmora Seas from board research ships of Shirshov Institute of Oceanology RAS the possibility of 'yellow substance' concentration determination in productive and polluted waters by one of the four optical methods was shown. The first method is based on the contact measurements of the vertical light attenuation coefficient at 500 nm with descending devices. The second method uses remote measurements of the sea-water radiance coefficient spectra from board a moving ship with three-channel spectrophotometer. The water type optical index is calculated from the obtained sea water radiance spectrum, then using the appropriate classification the main natural admixtures concentrations are estimated. According to the third method 'yellow substance' concentration is estimated from the measurements of sea water fluorescence intensity in blue-green spectral band (approximately 440 nm) by laser remote sensing of water surface in UV. The results of 'yellow substance' concentration estimation in sea water by these three methods were proved by the comparison with the concentration measurements data obtained by the two-ray laboratory photometer in filtrated samples of sea water taken at the stations.

In the report, we present and discuss the results of comparison between domestic photomultiplier tubes (PMTs) FEU- 130 coupled with amplifiers-discriminators and PMT R7207-01 coupled with HAMAMATSU C3866 amplifiers-discriminators, used in ozone sensing lidar. It is shown that, because photomultiplier R7207-01 has higher counting rate than FEU- 130, it can provide ozone retrievals in a 4 - 6 km wider (upward plus downward) altitude range.

The report presents the results of lidar studies of dynamics of the vertical distribution of the optical characteristics of stratospheric aerosol layer (SAL), obtained at the Siberian Lidar Station of the Institute of Atmospheric Optics SB RAS (Tomsk, 56.5 degree N, 85.0 degree East) since 1986. In the report it is shown that, under background SAL conditions, the vertical aerosol distribution has no seasonal (winter-summer) variations; while the altitude behavior of aerosol backscattering coefficient is well fitted by exponential function. We think that both of these characteristics can be considered as criteria in determination of background SAL state in midlatitudes of the northern hemisphere. The level of integrated aerosol scattering in 1996 - 2000 was close to, or even less than, that in 1989 - 1990, when low aerosol content was observed in the stratosphere; this obscures somewhat the existing hypothesis that the background stratospheric aerosol mass increases by 5% per year due to anthropogenic factors. Also considered are the anomalous variations of aerosol content at altitudes above 25 km, that were observed in January-February 2000.

Between July 12 and 24, Institute of Atmospheric Optics SB RAS had conducted an expedition along Ob river in which a spectrophotometer was used to record spectra in the wavelength ranges 290 - 340 nm and 430 - 450 nm. These spectra were then used to calculate the total ozone and slant NO₂ content and to reconstruct the NO₂ profile and total NO₂ content. In this work we describe the used spectrophotometer and discuss the obtained results.

We have derived a lidar equation allowing for contribution from multiple scattering (MS) that enables one to describe polarization properties of the lidar returns. An algorithm is also proposed to reconstruct the profiles of scattering coefficient and lidar ratio (backscattering phase function) under conditions of a priori uncertainties. Some results are presented in the paper on retrieval of optical parameters of clouds from lidar return signals calculated by the Monte-Carlo method.

Some results of lidar sensing of the ozonosphere in February and March of 1996 - 1999 at the Siberian Lidar Station (SLS) in Tomsk (56.5 degrees North, 85.0 degrees East) are presented. Observations shown that higher ozone contents in 1996 and 1998 were accompanied by a temperature rise in the middle stratosphere. High correlation between the vertical distribution and the total content of ozone in the lower stratosphere was found. The correlation analysis of vertical distributions of ozone and temperature revealed a significant positive correlation in the layer from 18 to 25 km as well as a significant negative correlation in the layer near 13 km. Altitude trends in the ozone content and the temperature in the stratosphere indicates a marked decrease of ozone and cooling of the atmosphere at altitudes of 22 - 30 km as well as an increase in the ozone content in the lower stratosphere, at the heights from 14 to 16 km. Trends in the NO₂ content in 5-km layers in the stratosphere also indicate a statistically significant decrease in the NO₂ content within the layer from 30 to 35 km.

Backscattering of light by hexagonal ice columns and plates has been calculated by means of a ray-tracing code. A gigantic peak of backscattering is found at the angle of about 32.5 degrees between the principal axis of a particle and incidence direction for both hexagonal ice columns and plates. This peak is explained by multiple total internal reflections inside the crystals that take place for a part of incident rays. The obtained results on backscattering efficiency allow somebody to calculate backscattering by an ensemble of the hexagonal ice cylinders of various sizes, shapes and orientations. Backscattering Mueller matrix has been calculated, too. Slant lidar remote sensing of cirrus clouds for discrimination between aligned columns and plates is suggested as an application of the results obtained.

The method of calculation of the brightness coefficients for the upwelling radiation from the land surface water is presented. Satisfactory agreement of calculated and experimental spectra is achieved via the incorporation of the additional optically active components in the calculation. The analysis of the position of experimental spectra in the space of the optical states allows one to estimate the state of the aquatic ecosystem using the notions which do not directly include the concentration of the components.

It is well known that data obtained from measurements of turbulence intensity, wind velocity profiles, and temperature at the altitudes of 10 - 15 km signify the zones of sharp changes near the tropopause. In this context it is essential to distinguish the footprint of the aircraft from characteristic of nondistributed turbulence. So this work is still continue in the following directions: atmospheric characteristic at altitudes of 10 - 15 km, turbulence characteristic at altitudes of 10 - 15 km, characteristic of aircraft engines, especially for B-747 and IL-86 planes, at altitudes of 10 - 15 km; characteristic of aircraft foot prints under conditions of real flight. And direct measurements of turbulence and refraction are performing in a plane footprint at the ground level. We are assuming to construct the model of atmospheric turbulence on the high- elevated paths along the long distance propagation.

It is represented equations, which define movement of crossing points trajectory of an optical airborne lidar axis with plane surface at fixed and basic coordinate system. On forming of a cone scanning movement trajectory is cycloid and at plane scanning is sinusoid. Functional dependencies to representing density distribution of spots on a surface are obtained graphically. This density distribution depends on: sensing parameters (repetition frequency of laser pulses), scanning parameters (frequency of scanning and deflection angle), flight (flying altitude and velocity).

The present work is aimed at quantitative estimation of the capabilities of remote detection of aerosol and gas leakages from distances 0.5 - 15 km with an airborne DF-laser lidar, placed onboard an aircraft or a helicopter and operating with a topographic target, by numerical modeling. The requirements for guiding the development of this lidar system are also formulated.

The relations between intensities of light scattering indicatrix and relative refractive index of a homogeneous sphere have been studied analytically and numerically for large optically 'soft' particles. The regions where solution of inverse problem is available have been determined. The obtained results reveal the opportunity of determination of relative refractive index for individual and suspension of spherical particles from experimental indicatrix.

Physicochemical transformations on the alkali-halides crystals surface by the high-energy irradiation and cold air plasma influence were studied. The formation of the new compounds such as MeNO₃, MeNO₂, MeXO₃, MeXO₄ was set up by the IR-spectroscopy.

The results are compared of investigation of the continuous extinction of visible and IR radiation and the continuum absorption by water vapor in the wavelength range 10.6 micrometer obtained both in field experiment and laboratory chamber. The reliability is confirmed of the results of investigation of the continuous extinction of optical visible and IR radiation that non-linearly depends on absolute humidity of air. The possible reasons are considered leading to the increase of minimum values of the extinction coefficients as absolute humidity increases. One can conclude based on the analysis that the physical reason of the continuous absorption can be absorption by fine aerosol that does not scatter radiation in visible wavelength range.

Some preliminary results of investigations of optical and microphysical characteristics of surface layer aerosol by means of spectropolarimeter are presented. The daily measurements were carried out in February - April 2000 at Zvenigorod Scientific Station of the Institute of Atmospheric Physics. Spectropolarimeter measured the spectral dependencies of the polarization components of direct scattering coefficient D at three angles (phi) equals 45 degrees, 90 degrees, 135 degrees in spectral region (lambda) equals 0.4 - 0.75 mcm. During measurements period about 900 records were obtained. On the base of this optical information, the inverse problem was solved -- particle size distributions and complex refractive indices n + ik were obtained. The statistical behavior of some optical and microphysical characteristics and their connections with basical input modeling parameter -- scattering coefficient (sigma) was considered. It was established that the spectral dependencies of D are described good by Angstrom's formula D approximately (lambda) ^-(alpha ), and the high correlation between (sigma) and Angstrom's exponent (alpha) exists (the correlation coefficient R approximately equals 0.7). The refractive index of 'dry' aerosol is also correlated with (sigma) , i.e. the mean chemical composition of aerosol particles changes with (sigma) change. The instrument was supplied by an air flow heater which allowed to measure the optical characteristics of 'dry' aerosol and to estimate the aerosol condensation activity. The last can be estimated from the reaction of aerosol optical characteristics on variations of the relative humidity Rh of air and is described often by so-called Hanel's formula D approximately (1-Rh)^-(chi ). The (chi) parameter was estimated for about 500 realizations of directed scattering coefficients D. It was found that its distribution is close to normal one with mean value (chi) equals 0.55 and variance S equals 0.3. The close connection between (chi) and scattering coefficient (sigma) of dry aerosol is absent (correlation coefficient R equals 0.35), but with (sigma) decrease, the variance of (chi) increases strongly. The dependencies of the sensitivity of different particle sizes e (eta) (r) on Rh changes were also considered.

By the some estimation, about 150 tons of the meteoric matter are fall on the Earth every day. Some researchers note coincidence of the periods of activity of the most powerful meteoric stream with the periods of intensive falling of atmospheric precipitation. The unique meteoric stream Leonids represents the great interest as an example of possible correlation between meteors and power precipitation. The comet produced this stream is well known as Tempel-Tuttl comet, its orbital period is 33.3 years. With the same periodicity, the sharp strengthening of activity of a stream, which is called meteoric shower, is observed. Such meteoric stream during a night could cover the average monthly norm of fall of meteoric bodies at once in tens time. The analysis of meteorological data shows, that the winters of 1933, 1966, 1998 and 1999 years of a maximum Leonids activity are characterized by huge amount of snow. These anomalies have resulted in disasters in some of region. Under our suggestions, the anomaly rate of falling precipitation can be explained by the meteoric dust, which plays the role of the nucleuses of condensation. Thus, taking in to account the dada of regular meteoric stream, it's possible to make long term weather forecasting with the more preciseness.

The assessment problems of the environmental impact of atmosphere pollution caused by gas burning in torches on forest-swamp ecosystems of West Siberia are considered. Geoinformation approach to the assessment of oil production impact based on the combination of sanitary-hygienic and landscape-geochemical approaches is reported. A pilot territory where main natural complexes are swamps of different types, coniferous-leaf-bearing forests and pine forests is described. The areas of polluted landscapes depending on the volume of oil production and normalized pollution levels are determined. The results may be applied for assessment of environmental impact of oil production within other territories with a similar landscape structure.

Results of investigation of 1998 total ozone at the both of hemisphere stratospheric circumpolar vortexes using Earth Probe/TOMS satellite data are presented. The rate of axial rotation of the vortexes at the level of the maximum ozone concentration was estimated, the average rate culminates 16 degrees per day in the South hemisphere and 6 - 8 degrees per day in the North hemisphere. The stratosphere vortex alters essentially after 8 - 10 days.

The analysis of processes of sulphur and nitrogen combinations distribution and transformation above the Southern Baikal was carried out using non-stationary spatial numeric model based on hemi-empiric equation of turbulent diffusion. Their aim was to study the behavior of admixtures at North-Eastern, South- Eastern and Western wind flows. In the radius 10 km from sources the calculated concentrations sulphur do not exceed 0.1 (mu) g/m³, nitrogen -- 0.05 (mu) g/m³. The discards of enterprises of near-shore zone influence much more negatively to Southern Baikal at Western wind with the rate of 5 m/s than at North-Eastern and South-Eastern ones with the same rate.

A refined integrated technique of objective analysis of the mesoscale geopotential field based on the combination of the method of optimal interpolation and of the modified method of clustering of arguments and developed to estimate the horizontal components of the geostrophic wind required for numerical forecasting of atmospheric pollution without wind velocity measurements is considered. Statistical estimates of the quality of the proposed integrated algorithm based on the long-term data of observations at aerological network representing a typical mesometeorological polygon are discussed for the barometer altitudes 975 - 800 hPa.

Mathematical model have been used for calculation of sulfur, nitrogen and small gas compounds concentration in atmosphere over Lake Baikal during meteorological conditions typical for December and April. The contribution of enterprises located in a town polluting Lake Baikal with sulfur and nitrogen compounds is estimated. Is shown that in December the main pollution is contributed by plants of Slyudyanka and Baikalsk. During April contribution of Irkutsk-Cheremchovo enterprises is significantly increases.

In this paper the results of the measurements of methane concentration in the period from March to May, 2000 are presented. For the measurements of the methane background concentration the gas-analyzer with tunable diode laser was used. The correlation coefficients between methane and CO₂, NO₂, O₃, as well as the temperature were estimated.

The purpose and functional capabilities of the Web information-computational system (ISC) 'Atmospheric Spectroscopy' (http://spectra.iao.ru) are presented. ISC is oriented on operations with databases of the high resolution spectra and designed for both placing at one's disposal the reference information on these spectra and solving traditional problems of the atmospheric optics. The experimental results on absorption by line wings and the possibility to calculate the absorption using different theoretical and empirical line wing shapes are discussed in the case of the CO₂ and H₂O molecules. The basic concepts of the atmospheric spectroscopy used under the ICS designing are described.

In this paper we consider the methodological problems of compiling the data bank of absorption coefficients of atmospheric gases. The data bank includes high- and medium- resolution absorption coefficients. Various methods of compression, archiving, and interpolation of data are considered. Specialized applied programs are proposed to be developed for operating the data bank.

This paper aims to select an accurate and numerically efficient second-order closure model of turbulence to predict dispersion of pollution in the atmospheric boundary layer. An one-equation E-model suggested by Mellor and Yamada, two- equation E-(epsilon) model by Duynkerke and E-1 model with algebraic relations for Reynolds stresses and turbulent fluxes for conditions of 33 - 34 days of the Wangara experiment are compared. Ii is shown that the later model more accurately predicts data of observation but it needs more computational time.

The comparative research of the chlorophyll contents for number of wood plants by traditional spectrophotometric and fluorescent laser methods is carried out. The seasonal changes of the chlorophyll sums in the spring-summer period at coniferous and deciduous wood plants are analyzed. The supervision over changes in the chlorophyll contents in connection with a withering of needles and leafs are carried out. The experimental results are received by spectrophotometric and lidar methods of study of a course of chlorophyll seasonal dynamics and pigment complex destruction of during a withering of needles and leafs of wood plants. The results of the joint analysis have shown identity of results received essentially by various methods.

The problem of CO₂ balance is a basic in the biosphere study and in the prediction of consequences of the global climate change due to anthropogenous impacts. The growing mires are the unique ecosystems among the terrestrial biosystems capable to fix the atmospheric CO₂ for a long period. The CO₂ emission from peatlands into the atmosphere is caused by mineralization processes of organic substances taking place due to drainage. The quantity of carbon dioxide emission from the peatland or from the peat deposits surface is an integral indicator of the transforming processes intensity in the peat. Different physical-chemical methods are used in the CO₂-gas-analysis. The aim of this work is a comparison of the hemosorption and optoacoustic gas- analysis methods. The outlines of the methods and their characteristics is also presented. The intercalibration was carried out under maximum possible identical conditions of the experiment. The CO₂ concentration and CO₂ emission kinetics at mineralization process of peat were measured simultaneously by both methods. It was shown that the results are in good agreement.

Coniferous trees are characterized by a high sensibility to an atmospheric pollution. Therefore, they are widely used in contamination level indication. Methods, basing on the chlorophyll fluorescence recording, are among the fastest methods of plants physiological state definition. In the present work the physiological state of coniferous trees, growing in several districts of Tomsk City with different degree of air pollution was investigated by fluorescent methods. It was found that in winter-spring time the fluorescence intensity of the trees in stronger polluted areas is higher. The reason is that the weakened plants can not reach the state of the deep dormancy. Therefore, under artificial removing, they overpass this state earlier, showing the higher physiological activity in comparison with plants of the pure sites.

Similarity theory and dimensional analysis are applied to the construction of a relationship for the spectral aerosol extinction coefficient in the visible atmospheric window 0.48 (DOT) 10^-4 cm < (lambda) < 0.76 (DOT) 10^-4 cm. For maritime mist the results allow one to compare the dependence of the spectral extinction coefficient on humidity as determined in situ with known laboratory observations on the variation in the radius of aerosol particle in moist air. Raoult's modified law is used to show that the variation in the optical properties of soluble aerosol is entirely determined by the variation in the average radius of particles depending on humidity.