The Bay of Fundy
It is impossible to talk about the Bay of Fundy without talking about tides. The ebb and flow of the Fundy tides are equal to the output of 250 nuclear power stations. This massive amount of untapped energy fuels a fragile ecosystem that provides a nutritious food supply for numerous species of bottom-dwelling organisims, birds, fish and the world's largest mammals, whales.Twice a day the Bay of Fundy fills and empties from the gravitational pull of the moon and the sun on the earth. Often the tides begin with a significant wave called The Bore. One of the finest examples of the Bore in Nova Scotia is on the largest river in the province, the Shubenacadie. The Bay of Fundy provides the fuel for the exciting Tidal Bore on the Shubenacadie River system. There are several companies in the region providing rafting tours as this wall of water advances up the river.Tides in the Bay of Fundy proper (along south western Nova Scotia) can reach a height of 3.5 meters (11 ft.), while tides near the head of the Bay (in the Minas Basin into which the Shubenacadie River flows) can rise and fall 13 meters (43 ft.) on average and reach an unbelievable 16 meters (53 ft.) during the springtime.
While the gravitational forces of the sun and moon combine to create a continuum of tidal action the world over, it is the unique shape of the Bay of Fundy that contributes to the extraordinary high tides experienced here.The Bay of Fundy is 290-kilometer-long (180 miles) in length. The mouth of the Bay of Fundy is 100 km (62 miles) wide and between 120 and 215 meters (400-700 feet) deep. Frequently described as funnel-shaped, this amazing body of water gradually narrows until it splits to form Chignecto Bay and the Minas Basin. Becoming gradually shallower, Chignecto Bay splits into Shepody Bay and Cumberland Basin, then Shepody Bay narrows and splits again into the Memramcook and Petitcodiac Rivers.
It is here, near this junction of rivers that the flowerpot formations of the Hopewell Rocks are found. The distance across the Bay of Fundy at this point is about 2.5 km (1.5 miles) and the depth at low tide about 14 meters (45 feet).
The highest tides of the Bay of Fundy are due to two unique characteristics of this finger of the Gulf. The gradual tapering and shallowing that constricts the tidal flow, causes the waters to rise from an average of one meter (3 feet) found elsewhere in the world to the 16-meter (52 feet) tidal range found at the head of the Bay of Fundy.
The second factor is the precise dimension of this incredible body of water. Every basin of water has its own natural rhythm and at 290 km (180 miles) long, the time it takes for the tide to flood the length of Bay of Fundy is nearly identical to the time it takes for the tide to come in from the adjoining Gulf of Maine.
This resonance - the meshing of these two rhythms - means that the tidal range is amplified. Called the "Seiche Effect", this amplification is frequently compared to the wave action produced by a child sloshing water back and forth in a bathtub, each wave higher than the one previous. It is this comparison which led to the Bay of Fundy being called 'the world's largest bathtub'.
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