Monochrome rainbow


A monochrome or red rainbow is an optical and meteorological phenomenon and a rare variation of the more commonly seen multicolored rainbow. Its formation process is identical to that of a normal rainbow (namely the reflection/refraction of light in water droplets), the difference being that a monochrome rainbow requires the sun to be close to the horizon; i.e., near sunrise or sunset. The low angle of the sun results in a longer distance for its light to travel through the atmosphere, causing shorter wavelengths of light, such as blue, green and yellow, to be scattered and leaving primarily red.[1]In the lower light environment where the phenomenon most often forms, a monochrome rainbow can leave a highly dramatic effect.


Unenhanced photo of a Red Rainbow, taken near Minneapolis, Minnesota, USA in July 1980
A double Red Rainbow taken from Cedar Point beach in Sandusky, OH. August 29, 2022. Sunset