Ocean tides affect our planet in many ways. Shaping our coastal beaches, ridges and occasionally remodeling our inland areas for the good or not so good.

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Good tide

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Bad tide

Spring and Neap Tides

Tides occur everyday, effected by the rotation of the Earth around the Sun and the Moon around the Earth. This causes the tides created to change where they occur. When the Sun and the Moon are aligned on the same side of the Earth, the tide caused their combined action is higher than normal and is called a spring tide. This reoccurs every 14 days, at new Moon or full Moon. When the Sun and the Moon form a right angle with the Earth, the gravitational forces of the Moon and Sun are in opposition and result in a weaker, intermediate tides called neap tides. These also take place every two weeks, at the first and third quarters of the Moon.
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Because tides depend on the rotation of the Earth and that the Moon and the Earth around their common center of mass, the time of high tide and low tide at any point in time can be predicted. The solar time has a period of 12.41 hours (because of the monthly rotation of the Moon around the earth). The Moon's closest approach to the Earth is at perigee, and the farthest point in its orbit is at apogee, the mean between the two being about 238,857 miles (384,403 kilometers). When perigee coincides with the spring tides, they rise about 20 percent higher than normal.

Work Cited: 1.http://upload.wikimedia.org/wikimedia/commons/f/f8/katrina-14512.jpg
2.http://upload.wikimedia.org/wikimedia/commons/9/9c/WA_Airport_Copalis.jpg
3. Dixon, Dougal. "The Planet Earth." The World Encyclopedia of Sciences. 1989 ed.
4.http://upload.wikimedia.org/wikimedia/commonsd/d2/Tide_diagram.png