Question
Wed February 13, 2013 By:
 

why clouds look white in clear sky?

Expert Reply
Wed February 13, 2013
The whiteness of the clouds is due to light of all colors being dispersed by the water/ice of the clouds. Clouds quite a distance away appear yellow due to the blue wavelengths being dispered more than the yellow and red wavelengths by the air and particles in the air (the 'clear' sky is blue!)
Not all clouds are pure white, however, for those that are white, it is due to their altitude and the reflection of sunlight.
Ask the Expert