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<Atmospheric optics> studies how <light> is redirected, scattered and absorbed by an atmosphere. Spatial changes of <refractive index> bend paths, suspended particles produce <scattering of light>, and moving variations of <refractive index> distort a distant source's <wavefront>.

The distinction is experimentally useful. A small source viewed through rising warm air changes shape and position even without an absorbing obstacle, while a cloudy beam path can lose direct <radiant power> through <scattering of light>. An <optical telescope> must therefore contend with both atmospheric transmission and changing <optical aberrations>; a large aperture alone does not guarantee a sharp image.


 Atmospheric optics (source code)