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The Spring 2011 issue of The Earth Scientist is focused on modernizing seismology education. Thanks to IRIS, you can download this issue for free as a pdf. Print copies are available in our online store.
This is a photo of mammatus clouds, taken in Weld County, Colorado.
Click on image for full size
Photo courtesy of Gregory Thompson

Mammatus

Mammatus clouds are pouches of clouds that hang underneath the base of a cloud. They are usually seen with cumulonimbus clouds that produce very strong storms.

Mammatus clouds are sometimes described as looking like a field of tennis balls or melons, or like female human breasts. In fact, the name "mammatus" comes from the Latin word mamma, or breast, because of this.

Last modified November 30, 2007 by Becca Hatheway.

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