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Young Voices for the Planet DVD in our online store includes 8 films where students speak out and take action on climate change.
An extreme low tide in winter. Image taken of the Maryland coastline on January 1, 1998. In this image, you can see small pools of water left when the tide went out and footprints of someone who walked in the sand during low tide. Both of these features will be covered up when the tide begins to increase again and the water level rises.
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Courtesy of NOAA

Tidewater

Have you ever walked along the same beach at different times during the day? Did you notice that sometimes the water was higher up on the beach than at other times? Changes in the height of ocean water on a beach are often caused by tides. When the ocean comes the highest up on the beach, it is called high tide. When the water is farthest out, it is called low tide. High tide might wipe out a sand castle you built that was on dry sand before! Low tide might give you the chance to look for more sea shells! One thing is for sure, low tide can look really different than high tide!

Tidewater is water that is affected by tides. A tidewater region is a region that is affected by tides. When you hear someone say they live on the coast of an ocean or sea, they live in a tidewater region. Rivers that flow into the ocean, estuaries, and salt marshes are also affected by the tides and so are important parts of a tidewater region.

Last modified June 1, 2010 by Lisa Gardiner.

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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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