Contents: Enigma of the daytime sky and the discovery of the scattering of light Description of light and the properties of the medium in the scattering event Atmospheric transparency and aerosols Polarization chart of the sky, anisotropy of molecules, and multiple scattering Brightness chart of the sky and the function of scattering Optic exploration of the atmosphere and the problem of interpretation of the data Scattering of light in clouds and in fogs, and related problems Radiation climatology and the optics of aerosols.
The work is devoted to study of the basic factors determining the processes of light scattering in the terrestrial atmosphere. The results of sky brightness observations are compared with theoretical calculations. On the basis of data of direct measurement, the role of light reflected from the underlying surfaces, pure absorption, curvature of the earth, stability of the atmosphere, anisotropy and other factors are analysed. The methods of determination of atmospheric transparency, monitoring stability, scattering indicatrix, and the like are examined.
This is the eleventh volume in the series Light Scattering Reviews, devoted to current knowledge of light scattering problems and both experimental and theoretical research techniques related to their solution. The focus of this volume is to describe modern advances in radiative transfer and light scattering optics. This book brings together the most recent studies on light radiative transfer in the terrestrial atmosphere, while also reviewing environmental polarimetry. The book is divided into nine chapters: • the first four chapters review recent advances in modern radiative transfer theory and provide detailed descriptions of radiative transfer codes (e.g., DISORT and CRTM). Approximate solutions of integro-differential radiative transfer equations for turbid media with different shapes (spheres, cylinders, planeparallel layers) are detailed; • chapters 5 to 8 focus on studies of light scattering by single particles and radially inhomogeneous media; • the final chapter discusses the environmental polarimetry of man-made objects.
Light scattering by densely packed inhomogeneous media is a particularly ch- lenging optics problem. In most cases, only approximate methods are used for the calculations. However, in the case where only a small number of macroscopic sc- tering particles are in contact (clusters or aggregates) it is possible to obtain exact results solving Maxwell’s equations. Simulations are possible, however, only for a relativelysmallnumberofparticles,especiallyiftheirsizesarelargerthanthewa- length of incident light. The ?rst review chapter in PartI of this volume, prepared by Yasuhiko Okada, presents modern numerical techniques used for the simulation of optical characteristics of densely packed groups of spherical particles. In this case, Mie theory cannot provide accurate results because particles are located in the near ?eld of each other and strongly interact. As a matter of fact, Maxwell’s equations must be solved not for each particle separately but for the ensemble as a whole in this case. The author describes techniques for the generation of shapes of aggregates. The orientation averaging is performed by a numerical integration with respect to Euler angles. The numerical aspects of various techniques such as the T-matrix method, discrete dipole approximation, the ?nite di?erence time domain method, e?ective medium theory, and generalized multi-particle Mie so- tion are presented. Recent advances in numerical techniques such as the grouping and adding method and also numerical orientation averaging using a Monte Carlo method are discussed in great depth.
The work is aimed at the review of hot topics in modern light scattering and radiative transfer. A special attention will be given to the description of the methods of integro-differential radiative transfer equation solution. In particular, the asymptotic radiative transfer and the method of discrete ordinates will be considered. A comprehensive review of light absorption in the terrestrial atmosphere will be given as well. The inverse problem solution will be reviewed as well.
Following the rapid developments in the UV-B measurement techniques and the rapidly growing research in the field in the late 80's and early 90's, we organized a large gathering of distinguished experts in a NATO Advanced Study Institute, held in Halkidiki, Greece on October, 2-11. 1995. The Institute was organized so as to include state of the art lectures on most aspects of solar ultraviolet radiation and its effects. This was achieved by extended lectures and discussions given in five sessions by 27 lecturers and a demonstration of filed measurements and calibration techniques at the end of the Institute. The ASI began with the sun and fundamentals on solar radiative emissions and their variability in time and continued with the interaction of solar Ultraviolet with the atmosphere through the complex scattering processes and photochemical reactions involved. Particular emphasis was given to changes in atmospheric composition imposed by different manifestations of the solar activity cycle. as well as on the modelling of radiative transfer through the atmosphere and the ocean under variable environmental conditions. Overviews on the ozone issue. its monitoring and variability were extensively discussed with emphasis on the observed acceleration of ozone decline in the early 90's. This acceleration had as a consequence, significant increases in UV-B radiation observed at a few world-wide distributed stations.
