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The seasons are a well-known example of a cycle.
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What is a Cycle?

Do you know what a cycle is? You may have studied them in school!

Cycles are events that repeat. Some cycles are very simple and other cycles are very complicated. One example of a cycle is the days of the week -- Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday, and then back to Monday! Can you think of any other cycles? How about the seasons? Summer, Fall, Winter and then Spring…over and over and over it goes!

Earth scientists study cycles a lot. One of the cycles they study is the water cycle. Other complicated cycles are called biogeochemical cycles.

Last modified June 29, 2005 by Jennifer Bergman.

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The Spring 2010 issue of The Earth Scientist focuses on the ocean, including articles on polar research, coral reefs, ocean acidification, and climate. Includes a gorgeous full color poster!

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF