Photographer's Note

The tides on Earth are strongly influenced, in addition to astronomical factors, by the sizes, boundaries, and depths of ocean basins and inlets, and by Earth's rotation, winds, and barometric pressure fluctuations. Tides typically have ranges (vertical high-to-low) of a metre or two, but there are regions in the oceans where various influences conspire to produce virtually no tides at all, and others where the tides are greatly amplified. Among the latter regions are the Sea of Okhotsk, the northern coast of Australia, the Bristol Channel on the west coast of England, and in Canada at the Ungava Bay in northern Quebec, and the Bay of Fundy between New Brunswick and Nova Scotia. The tidal ranges in these regions are of the order of 10 metres.
The highest tides on Earth occur in the Minas Basin, the eastern extremity of the Bay of Fundy, where the average tide range is 12 metres and can reach 16 metres when the various factors affecting the tides are in phase (although the highest tides occur typically a day or two after the astronomical influences reach their peak).
The primary cause of the immense tides of Fundy is a resonance of the Bay of Fundy-Gulf of Maine system. The system is effectively bounded at this outer end by the edge of the continental shelf with its approximately 40:1 increase in depth. The system has a natural period of approximately 13 hours, which is close to the 12h25m period of the dominant lunar tide of the Atlantic Ocean.
The gentle Atlantic tidal pulse pushes the waters of the Bay of Fundy-Gulf of Maine basin at nearly the optimum frequency to cause a large to-and-fro oscillation. The grestest slosh occurs at the head (northeast end) of the system. Because Earth rotates counterclockwise in the Norhern Hemisphere, the tides are higher in Minas Basin (Wolfville-Truro area) than in Chignecto Bay (Amherst-Moncton area).
Although it is the gravitation of the Moon and Sun that raises the tides, the energy in the churning waters is extracted from the rotational energy of Earth spinning on its axis. Near Annapolis Royal, Nova Scotia, a tiny portion of this energy is being converted into commercial electrical energy in the only tidal power plant in the Western Hemisphere. The peak output of the Annapolis Basin generator is 20 megawatts, about 1% of Nova Scotia's electrical power capacity.
Tidal friction both lengthens the day and increases the size of the orbit of the Moon. The day is lengthening by about 1 second every 50,000 years, imperceptible on a human time scale, but of profound significance to Earth's rotation over a few billiion years. If the Sun does not first incinerate our planet, in the distant future there will come a day that is as long as the lunar month (each then equal to about 40 present days) and a more distant Moon will stand stationary in the sky, as does Earth now in theh lunar sky. But this situation will not endure, for solar tides will still be present and will cause the Moon to approach Earth once more.

The photos were taken at Five Island Campground, Minas Basin (first one at 7.30 AM and second one at 12.30 PM).

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Additional Photos by Vlad Ghiea (vlad_ghiea) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 54 W: 56 N: 199] (1086)
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