Examples of two very different tidal ranges

The tidal range is the difference between high and low tides. The range at one location may vary quite a bit, depending on the phase of the moon, etc. However, some locations typically have small ranges, while others have large ranges.

Wake Island- average range one foot

Wake is in the middle (more or less) of the Pacific Ocean, at 35N 134E. It is thus surrounded by water, with no major land mass within a thousand miles or so. The water in the larger area around Wake is quite deep, greater than 10,000 feet. However, Wake is the top of a sea mount that extends for a hundred miles or so around the island. Thus there is some build up if the two tidal waves that sweep around the earth each day. Otherwise, the range would be even less.

Head of Bay of Fundy- average range 50 feet

The Bay of Fundy is just to the North-East of the State of Main, between Nova Scotia and New Brunswick. As can be seen in the map to the left, the bay is a deep and confining space. Because the tides are so spectacular, they have been studied for some time, and the bay is a tourist attraction. It has been estimated that the water mass at the head of the Bay has a natural frequency of one cycle every 12 hours, essentially the same as the frequency of the tidal force.

For an intuative feeling for this range: the water level is rising or falling about foot every four minutes at the time of maximum change.

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