Nimbus clouds often mean that a thunder storm is brewing: there may soon be thunder and lightning. Get out of the swimming pool! Nimbus really just means a cloud that already has rain or snow falling out of it. Can you see the rain falling in the picture to the right?
So you often see the names of clouds combined: a cumulonimbus cloud is a cumulus cloud, a puffy thick cloud, with rain falling out of it, and a stratonimbus cloud is a stratus cloud, a gray blanket cloud, with rain falling out of it.
Bibliography and further reading about the atmosphere:
Karen Eva Carr, PhD.
Assoc. Professor Emerita, History
Portland State University
Professor Carr holds a B.A. with high honors from Cornell University in classics and archaeology, and her M.A. and PhD. from the University of Michigan in Classical Art and Archaeology. She has excavated in Scotland, Cyprus, Greece, Israel, and Tunisia, and she has been teaching history to university students for a very long time.
More about Professor Carr's work on the Portland State University website
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This is a great kit: mold your own human skeleton, put it together, attach the magnets and stick it to your fridge! Learn what's inside your body.
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