The influence of the optical interaction of clouds on the radiation fluxes in the atmosphere is studied. A model and a method for calculating the magnitude of the radiation interaction under multiple re-radiation between clouds are proposed. It is shown that the radiation interaction depends in a complex way on the optical and geometric dimensions of the clouds and their optical parameters. It is established that for certain optical sizes of clouds the radiation interaction between them is maximal. The position of the maximum of the radiation interaction between the clouds is determined by the scattering phase function radiation: with an increase in the degree of elongation of the scattering phase function, the maximum moves to the region of large optical thicknesses.
The transfer of radiation in a stratified atmosphere is considered taking into account the effect of the underlying surface. Analytical expressions for the calculation of the transmittance, reflectivity and absorption capacity of the layered dispersed medium are obtained. It is shown that the absorptivity is strongly dependent on the stratification of the optical parameters of the atmosphere. It is established that the absorptivity of the atmosphere is the smallest with the highest concentration of contaminants in the surface layer of the atmosphere, in which case the absorptivity is weakly dependent on the distribution of absorption in the atmosphere. The presence of reflecting surfaces on the upper and lower boundaries of the atmosphere significantly enhances the absorptive capacity of the atmosphere.
Consider the transfer of radiation in a stratified atmosphere. The analytical expressions for the calculation of transmittance, reflection and absorption ability of dispersed layered environment were obtained. It is established that the conservative scattering of radiation regime of the atmosphere is practically independent of altitude stratification of the aerosol. It is shown that the reflectivity of the atmosphere is only weakly dependent on the optical density of the surface layer with the absorption at any value of optical density of the upper layer and the single scattering albedo. The essential dependence of the absorptivity of the atmosphere from high-altitude parameters stratified atmosphere were established.
The authors have studied the radiation transfer in multilayer atmosphere. The analytical formulae for the calculation of the transmission coefficient, reflectance and absorption of dispersion media consisting of three plane layers were obtained. It was shown that absorption of dispersed media depends strongly on absorption layer’s position in dispersed media. The lowest value is marked when the layer takes place below of the media the light falls from above. Investigation of the radiation balance of the atmosphere is usually conducted on the basis of the theory of radiative transfer and numerical methods [1]. In conducting research using various models of the atmosphere [2-4]. Accuracy of the results depends on the accuracy of the approximation and taking into account all the effects that significantly affect the results, such as the effect of the spatial limitations of the dispersion medium [4-6].
The authors have considered the radiation transfer in triple dispersion media with reflective surface. The analytic for determining the values of reflectance and transmission coefficient of atmosphere consisting of three plane layers limited by the reflective surface were obtained. It was shown that stratosphere and bottom atmospheric layers even at low value of optical density and its weak change impact considerably the reflectance of the «triple dispersion media – reflective surface» at all magnitudes of substrate on reflectivity. It was ascertained that the increase of elongation degree phase function in a cloud layer results reflectivity of the whole dispersion media. This effect is similar to reduction of optical density of atmosphere cloud layer.
The paper is dealt with the laws of radiative transport within space limited scattering mediums depending on optical
dimensions of a cloud and its micro physical properties. Detected was the range of application for infinitely extended
dispersion medium and meanings of optical thicknesses at which the medium can be regarded as unlimited. In
accordance with these results the authors conclude the nebulosity influences the radiation balance of the atmosphere
depending on the cloud distribution according to their optical dimensions.
The paper has investigated transmission factor, reflectance and absorption factor for the volume of the space limited
dispersion medium depended upon optical parameters of the medium and radiation. Investigation was carried out
regarding the dependence of the scattering phase function of radiation upon the absorption wave-length and the line
form. Finally, results have been compared with data theoretically obtained from the radiative transport and based on the
assumption that radiation does not depend on the wave-length (within the spectral line) and space unlimited dispersion
medium.
The paper presents radiation distribution at output of space limited dispersion medium under various illumination
conditions of one of the volume sides. Obtained were formulas for radiation distribution and contrast with regard for
space limited dispersion medium. Increase of absorption in the medium increases contrast; the same result was observed
in increasing anisotropy of scattering phase function.
The influence of space limited dispersion medium on the radiation distribution and picture quality properties obtained
from the scattering medium of finite sizes have been investigated. Analytical expressions were obtained for calculation
of radiation distribution, border function and visibility of light fringe function. It has been shown that space limited
dispersion medium and lighting conditions influence much the picture quality properties.
The optical radiation absorbed by a dispersion medium of the finite size has been investigated. It has been showed that
the value of energy absorbed depends not only on individual properties of molecules but mainly on the optical volume
of medium that can be determinant in evaluating the amount of luminescence yielded. A new mechanism which
accompanies a concentrated quenching of luminescence has been discussed.
The paper is dealt with the rules of radiation transfer within stratified heterogeneous dispersion media. Research has been carried out in model media constituted of polystyrene latex with pre-set particle dimensions. A heterogeneous dispersion medium was achieved by a division into three homogeneous layers with different particles and hence different scattering phase functions of radiation. Transmission factors, reflectance and radiation yield through lateral faces have been detected in dependence of layer transposition. Experimental findings have been compared with design data.
The paper reviews and describes a new approach to the problem of radiation transmission in dispersion medium with particles of irregular shape. This problem is based on the use of radiation scattering phase function as integral parameters obtained on the basis of two scattering phase functions represented in two perpendicular planes. This conception of the scattering phase function is adapted to streaming methods for the radiation transmission problem. The analysis of results has been carried out with the help of the coefficient of skewness of scattering phase function and angular distribution radiation of the scattering volume.
The paper deals with radiation transfer in scattering volumes of various forms. Change of brightness body of scattering volume is analyzed by means of the asymmetry coefficient. The use of this coefficient allows appreciating the beginning of the remote mode and the utmost dimensions at which the medium can be considered unlimited in the cross-section. It also allows defining a transition region of optic dimensions at which the influence of absorption upon the brightness body form is significant. An invariant correlation was introduced which allows appreciating a precision of radiation balance calculation for scattering media of various forms.
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