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Name: Tim
Status: student
Age: N/A
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Date: N/A


Question:
Why are clouds white an not other colors?



Replies:
Hi Tim,

In fact, clouds are other colors, which gives you a strong clue as to why they are white. For example, when you look towards a sunrise or sunset, if there are clouds present, they take on the yellow / orange / red hue of the sunset. The water particles are scattering all the light that hits them. If they only have long wavelength light hitting them (as at sunrise or sunset) they appear red. But in the daytime the full sun hits them. As a result they scatter all colors of light and they appear white.

Regards,

Greg Bradburn


Dear Tim:

Clouds are white when they reflect the sun's light. The different particle sizes of water droplets in the clouds reflect all colors which, to our eyes looks white. But not all clouds look white. If the cloud is between us and the sun, the water soaks up (absorbs) the sun light and then, depending on how thick the clouds are, they can look gray or even black.

Hope this helps.

R. W. "Bob" Avakian
Instructor
B.S. Earth Sciences; M.S. Geophysics
Oklahoma State Univ. Inst. of Technology



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