The Bay of Fundy is located on the Atlantic coast of North America, on the northeast end of the Gulf of Maine between the Canadian provinces of New Brunswick and Nova Scotia. The bay is known for having the highest tidal range in the world. Because of the unique shape of the bay, the difference in water level between high tide and low tide can be as much as 48 feet (14 meters). During each tide cycle, more than 100 billion tonnes of seawater flows in and out of the Bay of Fundy which is more than the combined flow of the world’s freshwater rivers. Bay of Fundy experiences one high and one low tide twice a day. It takes on average 6 hours and 13 minutes for low tide to grow into a high tide and another 6 hours and 13 minutes for the water level to drop from high tide to low tide. This frequency gives each visitor a chance to see at least one high and one low tide during the daylight hours any time of year.
The immense energy of the tides stir up nutrients from the ocean floor, the mud flats and salt water marshes, providing an abundance of food for the birds, whales, fish and bottom dwellers of the ocean. This highly productive, rich and diverse natural ecosystem has shaped the environment, the economy and the culture of the Fundy region. The effect of the world’s highest tides on the Bay’s shores has created dramatic cliffs and awesome sea stacks. The red sandstone and volcanic rock have been worn away to reveal fossils from over 300 million years ago.
Composite photo showing difference in water level during low tide and high tide. Photo credit
Why are the Bay of Fundy Tides the Highest?
The average tidal range of all oceans around the globe is 1 meter (3ft), so how can the tidal difference in the Bay of Fundy reach up to 16 meters? This tidal phenomena exists because the bay has a few distinct features: a substantial amount of water and a unique shape and size that causes resonance.
A liquid in a basin has a characteristic period of “oscillation” and, once set in motion, the liquid will rhythmically slosh back and forth in this time period. The frequency at which it oscillates depends on the length and depth of the basin.
On a small scale, picture a bathtub with water sloshing around in. It takes just seconds to slosh back and forth. Due to the enormous size, the unique funnel shape, and the immense depth of the Bay of Fundy, its natural period of oscillation is somewhere between 12 and 13 hours. That oscillation is in perfect sync with the Atlantic ocean tide flooding into the bay every 12 hours and 26 minutes, this results in “resonance”.
Imagine someone on a swing, going back and forth, reaching the same height every time. Now imagine someone else giving the person on the swing a solid push every time the person starts to move forward again. They are obviously going to go much higher this time.
Well, the water in the Bay of Fundy is like the person on the swing and the tides coming in from the Atlantic Ocean are like the person giving the push. Its because the water in the bay moves back and forth in sync with the oceanic tides outside that there is such a large increase in the tidal range towards the head of the Bay.
The bay’s shape and bottom topography also have a secondary influence on the tides. The bay is shaped like a large natural funnel; it becomes narrower and shallower towards the upper part of the bay, forcing the water higher up onto the shores.
Watch the timelapse video of the Bay of Fundy tides after the pictures.
Low tide. Photo credit
High tide. Photo credit
The top image was taken at 11:32am and the bottom photo was captured at 5:24pm on the same day. Photo credit
Tides entering the harbour. Photo credit
Tide has almost reached its peak. Fishing boats are fully afloat, and one of the trawlers has left the harbour. There was about 1 hour and 45 minutes between this and the previous picture. Photo credit
Hopewell Rocks, Bay of Fundy, at low tide. Photo credit
Hopewell Rocks, Bay of Fundy at high tide. Photo credit
Saw pretty drastic tides while in Brittany, at the extreme south point of it when I was a kid. (Brittany is the Celtic part of France; the part that sticks out to the west on maps, just under the British Iles.) At high tide, the water was licking the high cliffs, about 2-3m up, and low tide would reveal hidden caves in the cliffs and water pools in the sand that heated up from the sun. And the water was now 1/2km away!
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