A branch of meteorological physics or physical meteorology in which phenomena are seen occurring in the sky and are described and explained: Atmospheric optics is the study of the optical characteristics of the atmosphere or products of atmospheric processes.

The term atmospheric optics is usually confined to visible and near visible radiation, however, unlike meteorological optics, it routinely includes temporal and spatial resolutions beyond those discernible with the naked eye.

"Meteorological optics" is that part of atmospheric optics concerned with the study of patterns observable with the naked eye.

This restriction is often relaxed slightly to allow the use of simple aids, such as binoculars or a polarizing filter.

Topics included in meteorological optics are sky color, mirages, rainbows, halos, glories, coronas, and shines.