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Name: Marvin
Status: Other
Age: 50s
Location: N/A
Country: N/A
Date: N/A 

Why are ocean tides greater in some areas? My son just came back from Cape Hatterus NC and he said he saw very small tide changes.

The gravitational attraction, primarily of the moon, causes the water in the oceans to "rise" a certain amount, i.e. it bulges a bit on the side facing the moon, and on the side facing away from the moon. If the shoreline is long, wide and flat, this rise is spread out over a large surface area, so the "rise" is small. If the shoreline is a gorge, surrounded on three sides by cliffs there is no place for the water to go but UP, so the tide rises a great height. If memory is correct, the bay of Fundy, I think in Nova Scotia is the classic example.

It's really a bit more complicated than this because the tidal rise depends on other things such a approaching hurricanes or typhons, and on the landscape of the ocean floor off shore.

Vince Calder

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