Iridescence Above Cairo, Egypt
July 24, 2009
The photo above showing cloud iridescence above Cairo, Egypt was captured in the early morning on November 8, 2008. A low morning Sun lent fascinating hues to these opalescent clouds. Iridescence is a diffraction phenomenon. Light is deflected by very small and similarly sized water droplets typically found in altocumulus or altostratus clouds. The intensity of the color that’s displayed results predominantly from variations in cloud droplet size, and the pastel shades are caused by overlapping colors (interfering waves of light). Iridescence clouds are essentially fragments of coronas.