Cloud albedo

Cloud albedo is a measure of the albedo of a cloud. Higher values indicate that a cloud reflects a large amount of solar radiation or transmits a small amount of radiation.

Cloud albedo varies from less than 10% to more than 90% and depends on drop sizes, liquid water or ice content, thickness of the cloud, and the sun's zenith angle. The smaller the drops and the greater the liquid water content, the greater the cloud albedo, if all other factors are the same.

Low, thick clouds (such as ) primarily reflect incoming solar radiation, causing it to have a high albedo, whereas high, thin clouds (such as Cirrus) tend to transmit it to the surface but then trap outgoing infrared radiation, causing it to have low albedo. It contributes to the greenhouse effect.

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