Atmospheric aerosols, particularly dense, local clouds of smoke, dust and fog, have a variety of extinction, multiple scattering and thermal emission effects on propagation and imaging. This paper presents an approach to simulating realistic aerosol path-radiance effects that are not treated in the usual transmission codes. Depending on illumination and concentration, aerosol clouds may range in appearance from thin translucent wisps to opaque diffuse reflectors or emitters. Typically the clouds are inhomogeneous and have complex, finite geometries. Their radiative transfer properties are therefore particularly difficult to predict. This paper uses a method developed by the U.S. Army Atmospheric Sciences Laboratory to model and investigate the radiative transfer effects of such aerosol clouds under a variety of illumination conditions. The method is applied to show some interesting examples of the contrast and apparent temperature signatures of aerosol clouds themselves, the changes to signatures of partly obscured objects and the effect on received images at the sensor under various illumination conditions.
Donald W Hoock, Donald W Hoock,
"Modeling Path Radiance Effects From Aerosol Clouds", Proc. SPIE 0926, Optical, Infrared, Millimeter Wave Propagation Engineering, (10 August 1988); doi: 10.1117/12.945776; https://doi.org/10.1117/12.945776