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Listener Question: Moon & Tides
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Dave Thurlow, Host
 
Hi, I'm Dave Thurlow for The Weather Notebook. Today I have a question from one of our listeners:

"Hello, my name is Eileen Keim, from Concord, NH. I have a question. I've seen those little diagrams in schoolbooks explaining how the tide rises in response to the moon. And it shows a high tide both on the side directly under the moon and the side directly opposite the moon. And I suddenly started to wonder, how come? Why should there be a high tide directly opposite the moon instead of just a general high tide on the side with the moon attraction. I'd love it if you could answer that one for me."

Moon and Tides
 

Well that is a good question - you guys know the answer to that?...Great that's The Weather Notebook research staff. Well, ok. I'll just look it up in some books I've got here...just a second lets see... Oh ya here we go. The ocean tides are caused by three things -- the moon, a little bit by the sun, and by centrifugal force created by the earth and moon spinning in tandem. The moon's gravity forces the ocean toward it on the side of the earth facing the moon, but centrifugal force of the spinning earth/moon system forces the ocean to bulge on the side of the earth opposite the moon. Simply it's gravity and centrifugal force that lift the ocean waters skyward on all sides of the planet. If you have a weather question please call us a 1-888-724-6001, or search for answers on our website at mountwashington.org/notebook.

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