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The article discusses a study which presents a Fast Aerosol Retrieval (FAR) algorithm for the retrieval of aerosol optical thickness (AOT) and surface reflectance. It compares FAR and ART procedures such as the codes' input data preparation. It considers two satellite remote sensing problems such as aerosol model preliminary preference effects and cloud influence on adjacent pixels. It presents several tables and charts on the data collected including a chart on AOT values from FAR and ART.

For single scattering in a turbid medium, the Mueller matrix is the 4 x 4 matrix that multiplies the incident Stokes vector to yield the scattered Stokes vector. This matrix contains all the information that can be obtained from an elastic-scattering system. We have extended this concept to the multiple-scattering domain where we can define an effective Mueller matrix that, when operating on any incident state of light, will yield the output state. We have calculated this matrix using two completely different computational methods and compared the results for several simple two-layer turbid systems separated by a dielectric interface. We have shown that both methods give reliable results and therefore can be used to accurately predict the scattering properties of turbid media.

The conventional theory of image transfer through a scattering medium treats objects located upon reflecting surfaces. It is shown that, when an object is located inside a scattering medium and shields a part of space, ignoring the shadowing leads to incorrect results, especially for modern time-gating systems. We develop a general theory of image formation including the shadowing effect when an object is located inside a scattering medium. The example of the observation of a submerged object through a windy ocean surface is chosen to illustrate this theory. A few unexpected effects in imaging of a submerged object are found and discussed, including contrast conversion for a sinking object and higher contrast in the shadow image than in the image of the object itself. The conclusion that using the shadow image for detection of a submerged object can be more efficient than using the image of the object itself is of practical significance.

We propose the physically based parameterization of the radiative characteristics of liquid-water clouds as functions of the wavelength, effective radius, and refractive index of particles, liquid-water path, ground albedo, and solar and observation angles. The formulas obtained are based on the approximate analytical solutions of the radiative transfer equation for optically thick, weakly absorbing layers and the geometrical optics approximation for local optical characteristics of cloud media. The accuracy of the approximate formulas was studied with an exact radiative transfer code. The relative error of the approximate formula for the reflection function at nadir observations was less then 15% for an optical thickness larger than 10 and a single-scattering albedo larger than 0.95.

New analytical solutions for the local optical characteristics (extinction and absorption coefficients, asymmetry parameters of phase functions) of spherical polydispersions composed of comparatively large particles are derived. The geometric optics (GO) approximation is used to solve the problem. For the accuracy of the GO approximation to be improved, the edge effects were taken into account. A comparison with the data obtained by the use of the Mie theory shows a satisfactory accuracy of our analytical formulas. The simple formulas for the cloud local optical characteristics are derived.

A new analytical expression for the optical transfer function of multiple-scattering media such as clouds, mists, and dust aerosols is given in terms of their microphysical characteristics. The geometrical optics approximation is used to find local optical parameters of a scattering medium, including the simple approximation of the phase function, which is the key to the solution of the problem considered here. The optical transfer function is taken within a small-angle approximation of the radiative transfer theory. A comparison with Monte Carlo data shows a fairly satisfactory accuracy of our analytic formulas.

A new approach to calculating a light field with multiple scattering in media such as clouds, mists, and ocean water is given. It examines all characteristic properties of the real phase function and is applicable to a scattering medium of any optical thickness with an arbitrary single-scattering albedo. The phase function is represented as a sum of more simple functions. The radiance is given as a sum of appropriate components for which the equations, which can be solved by using a known method within domains in which they work best are obtained. The analytic solution of the problem of sunlight propagation in clouds and mists is given on this basis. It describes the complex multimodal angular radiance distribution. A comparison with different numerical calculations shows a fairly satisfactory accuracy of our analytic formulas.