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WHAT TO VISIT
THE BAY OF FUNDY - ONE OF THE MARINE
WONDERS OF THE WORLD
Highest Tides
By George
Ferguson
http://www.tourismnewbrunswick.ca/en-CA/HNThingsToDo/HNNaturalWonders/HNNWBayOfFundy.htm
http://www.bayoffundy.com/tides.aspx
The enormous tides
of the Bay of Fundy are truly one of the world's great natural wonders.
One hundred billion
tonnes of water flows into and out of the Bay on an average tide, twice
a day, creating rip-currents, seething up-wellings, swirling whirlpools
and a tidal range reaching 16m (53 ft) at the head of the Bay. The
volume of water receding & flowing is estimated to be 2000 times greater
than the daily discharge of the Gulf of St. Lawrence (Thurston, 1994).
The immense energy of the tides powers a highly productive, rich and
diverse natural ecosystem, in turn shaping the environment, the economy
and the culture of the Fundy region.
Tides are considered the heartbeat of
the oceans of our planet. They are defined as the response of the oceans
to the periodic fluctuations in the cosmic forces of the moon, and the
sun, and the perpetual spinning rotation of the Earth (Pinet, 1998).
This response is in the form of long, gently-swelling waves that are
generated throughout the seas and oceans of the world. These equilibrium
tides propagate from place to place and are reflected and dissipated
just as other long waves. Thus it is that the tide observed at a
particular place is not produced locally, but is the sum of tide waves
arriving from all over the ocean, each modified by its experiences along
the way. The average tidal range of all oceans around the globe is lm (3
ft).
And further galactic forces come into
play. During each phase of a new moon or a full moon, when earth, sun
and moon are aligned, higher tides result. These are referred to as
"spring tides" a term derived from the springing up of the water.
Conversely, twice each month when the sun and moon are at right angles
to the earth and opposing each other, the tidal ranges are slighter and
are defined as "neap tides" (Pinet, 1998). The tides along the
Atlantic coast are principally semi-diurnal, meaning there are two
significant high tides every 24 hours. Along the Nova Scotia Atlantic
coast, the tidal range is 1.5m - 2.5m (4 - 8 ft) and the tide arrives
and departs at approximately the same time everywhere. However, due to
the unique funnel shape and prodigious depth of the Bay of Fundy, the
water moves back and forth in sync with the oceanic tides outside. This
movement leads to a large increase in the tidal range towards the head
of the Bay. Tidal measurements in the Minas Basin are the highest
recorded in the world 16m (53 ft).
(Imagine bobbing in a small boat on
water that is deeper than a five-story building and in exactly the same
place in less than six hours . . . you can walk on the ocean floor).
And still there are other impelling
forces at work in the mighty tides of Fundy. The elementary laws of
physics establish that liquid in a basin has a characteristic period of
"oscillation" and once set in motion, the liquid will rhythmically slosh
back and forth (Cutnell and Johnson, 1995). The speed at which it
oscillates depends on the length and depth of the basin. The surface
rises first at one end, then at the other, while the level in the middle
remains constant. The natural period of oscillation in the Bay of Fundy
is approximately 12 hours. And by reason of the contours of the Bay,
Fundy's oscillation corresponds with, and is reinforced by, the rhythm
of the tides in the Atlantic ocean resulting in "resonance" - the second
oscillation induced by the arrival of the ocean tide, of the same speed
as the first, resulting in a higher tidal range (Thurston, 1994).
Along the interior Fundy coast, the
phenomenal tides have left conspicuous evidence of their power and
might: At Hopewell Rocks the tidal currents have carved and sculpted
towering statues of red sandstone. Topped by evergreens, they resemble
huge flowerpots and stand as one of many Fundy marvels. At St. Martin's,
the endless tidal action has carved out spelunker perfect sea caves. And
with each receding tide, vast nutrient-rich mudflats are exposed in the
Minas Basin.
The highest- profile phenomenon
produced by the tides is the world-famous Reversing Falls at
Saint John, where the majestic Saint John River plunges over cascading
falls and a narrow passage on its way to the ocean. Twice each day the
huge river must yield to the superior power of the Bay. As the tides
slowly rise above the level of the river, the falls reverse, and the
Saint John River flows upstream (Pinet, 1998).
A similar spectacle occurs at the head
of the Bay of Fundy in the form of Tidal Bores. Chignecto Bay and Minas
Basin form two arms at the head of the Bay, fed respectively by the
Peticodiac River and the Salmon River. At high tide, the extraordinary
volume of water in the Bay floods into the rivers. As the river banks
narrow, the compressing waters rise in a spectacular surge and a visible
standing wave, sometimes lm (3 ft) in height, as the maelstrom of
roaring, churning water races upstream at speeds close to 15 km per hour
(10 mph). Witnesses have likened the sound to that of an approaching
railway train, and first-time viewers are usually struck with awe and
fear (Thurston, 1994).
In broad overview, the stupendous
Fundy tides are a titanic catalyst to a succession of extraordinary
scientific, environmental and ecological wonders. Individually, they are
microcosms of the perfectly evolving elements of nature. Collectively,
they meld in concert to form a macrocosm considered one of the world's
most natural and unspoiled. And underlining the fragility of nature is
the certainty that with the continuous passage of time, the surging,
monumental tides will ultimately destroy themselves as they slowly erode
and disintegrate this unique basin.
 High
Tide in Chance Harbour, NB
Tide Height: 7 meters (23ft)
 Low Tide
in Chance Harbour, NB
Tide Height: .75 meters (2.4 ft)
Explore one of the world’s most dramatic and
dynamic coastlines
Visit Atlantic
Canada’s Bay of Fundy! Home to the highest tides in the world, the Bay
of Fundy is a 270km (170 mile long) ocean bay that stretches between the
provinces of New Brunswick and Nova Scotia on Canada's east coast. Each
day 100 billion tonnes of seawater flows in and out of the Bay of Fundy
during one tide cycle more than the combined flow of the world’s
freshwater rivers!
Hopewell Rocks,
situated at the head of the Bay of Fundy, is one of New Brunswick’s most
outstanding Provincial Parks and is the tourism icon used to showcase
New Brunswick and the spectacular Bay of Fundy. The sandstone and
conglomerate "flowerpot rock" formations, carved by giant tides that
regularly exceed the height of a four and a half story building, are a
geological wonder that has attracted visitors from the world over. A
walk on the ocean floor at low tide, allows visitors to view the
uniquely shaped rocks, while a totally different perspective of the
rocks is available only on a high tide sea kayaking excursion.
With ocean tides
the height of a four story building and a discharge of water that
exceeds that of every brook, stream and river on planet earth in a
single day, it is little wonder that The Bay of Fundy is recognized as
"A Marine Wonder of the World."
World’s
Highest Tides Ecozone
The
World’s Highest Tides Ecozone presents an extraordinary tidal landscape.
This includes the upper basins of the Bay of Fundy, where the peak tidal
range is around 15 m (50 ft) — five times higher than typical tides on
the rest of the Atlantic coast! The world’s highest tides can be
experienced as three different phenomena: tidal bores and rapids,
horizontal tidal effects, and vertical tidal effects.
How to
See the Tides
In the
World’s Highest Tides Ecozone, visitors can see two high and two low
tides each 24-hour period. The time between a high tide and a low tide
is, on average, six hours and 13 minutes. As such, you can reasonably
expect to see at least one high and one low tide during daylight hours.
High and low tide times move ahead approximately one hour each day, and
tide times vary slightly for different locations around the Bay. Check
with the community you are planning to visit for accurate high and low
tide times.
The name "Fundy" is thought to
date back to the 16th century when the
Portuguese referred
to the bay as "Rio Fundo" or "deep river".
Where to
See the Greatest Vertical Tidal Effect
The tidal
range is normally measured as a vertical distance: the change in the
ocean’s elevation from high tide to low tide. In the World’s Highest
Tides Ecozone, the tide’s vertical change can be 15 m (50 ft) or more.
The best way to see vertical tides is to visit small harbours around the
Bay that empty at low tide and then completely fill about six hours
later at high tide. Fishing boats that bob in the water alongside
wharves at high tide sit on the ground below at low tide. Wharves along
the Fundy coast in Nova Scotia (Halls Harbour, Parrsboro, and Advocate)
and New Brunswick (Alma and St. Martins) are good locations for viewing
extreme vertical tides. At Hopewell Cape, NB, visitors at low tide can
walk on the ocean floor among the incredible rock formations that the
tides have carved. As the tide comes in, visitors can see these
formations become small islands. The best way to see the tide’s vertical
change is to visit a site at high tide and then return to the same site
six hours later at low tide.
Low tide,
Hopewell Cape, NB
Hall’s Harbour,
NS low tide
Where to
See the Greatest Horizontal Tidal Effect
The tidal
range can also be observed as a horizontal change. In some parts of the
Bay, the tide retreats as much as five km (three mi.) at low tide,
leaving vast areas of the ocean floor exposed. In Chignecto Bay and the
Minas Basin, a fascinating inter-tidal zone of beaches, rock ledges, and
sand flats is exposed at low tide. At low tide, visitors are able to
walk on the ocean floor. The ocean floor is accessible at low tide
through local parks and beaches in communities all around the Bay of
Fundy’s coast. However, visitors who venture onto the inter-tidal zone
in Chignecto Bay and the Minas Basin at low tide must be very cautious,
as the tide can move extremely fast when it turns and starts to come in
again. At Evangeline Beach (NS), Dorchester Cape (NB), and Mary’s Point
(NB), huge flocks of up to 100,000 migratory shorebirds converge to
feast on the inter-tidal zone’s fertile mud and sand flats. Each summer,
this area exposed at low tide becomes a critical feeding area for birds
on their inter-continental migratory flight. Care must be taken not to
disturb migratory birds during their feeding period.
Low tide, Five
Islands, NS
Exploring sea
caves at St. Martins, NB
What is a
tidal bore?
A tidal
bore is a tidal phenomenon in which the leading edge of the incoming
tide forms a wave (or waves) of water that travel up a river or against
the direction of the current.
Bores
occur in relatively few locations worldwide, usually in areas with a
large tidal range such as the Bay of Fundy, and where incoming tides are
funneled into a shallow, narrowing river via a broad bay. The
funnel-like shape not only increases the height of the tide, but it can
also decrease the duration of the flood tide down to a point where the
flood appears as a sudden increase in the water level.
The word
bore derives through Old English from the Old Norse word bara, meaning a
wave or swell. In the Bay of Fundy region there are several excellent
places either to watch a tidal bore from the shore or to ride its waves
with an adventure tour company!
Where to
See Tidal Bores and Rapids
The Bay
of Fundy’s tides also cause tidal bores, rapids, and whirlpools.
Visitors can also take a thrilling jet-boat ride through Reversing Falls
in Saint John (NB) where the incoming tide reverses the river’s natural
flow and creates extreme tidal rapids. Cape d’Or (NS) and Cape Enrage
(NB) are great locations for seeing tidal rapids from shore. Intense
tidal whirlpools also occur around the coasts of Deer Island and
Campobello Island in New Brunswick.
Tidal bore rafting,
Shubenacadie River, NS
The
Science of the Tides
Tides are
the periodic rise and fall of the sea caused by the gravitational pull
of the moon and the sun on the Earth. Fundy’s tides are the highest in
the world because of an unusual combination of factors: resonance and
the shape of the bay. The water in the Bay of Fundy has a natural
resonance or rocking motion called seiche. You could compare this to the
movement of water in a bathtub. Although the water in a bathtub sloshes
from one end to the other and back again in a few seconds, it takes
about 13 hours for the water in the bay to rock from the mouth of the
bay to the head of the bay and back again. As the ocean tide rises and
floods into the bay every 12 hours and 25 minutes, it reinforces the
rocking motion. Likewise the seiche in the bay is sustained by the
natural resonance of the ocean tides. The bay’s shape and bottom
topography are secondary factors contributing to Fundy’s high tides. The
bay becomes narrower and shallower [from 130 m (426 ft) to 40 metres
(131 ft)] toward the upper bay, forcing the water higher up onto the
shores.
1-800-561-0123
At the
Hopewell Rocks,
Fundy’s tides, in combination with other forces of nature, have carved a
unique and diverse ecosystem.
http://www.baymountadventures.com/Rocks.htm
Deer Island, New Brunswick - Eastport, Maine
One of the most dramatic demonstrations of the
power of the tides is found in the Western Passage of the Passamaquoddy
Bay towards the mouth of the Bay of Fundy. “Old Sow” is the largest
whirlpool in the western hemisphere, the second largest in the world -
second only to the Maelstrom Whirlpool of Norway. Located between Deer
Island and Indian Island, this natural wonder can be seen from the
shores of Eastport, Maine. It is called “Old Sow” because of the sounds
that are heard from the churning waters.
This powerful
whirlpool is formed when the rising tide passes both sides of Indian
Island, takes a sharp right turn around the southern tip of Deer Island
to flood the Western Passage. A current of over 6 knots (11 km/hr or 6.9
mi/hr) has been experienced off Deer Island Point. In addition to the
waters pressing through the narrow straight, the waters are forced along
the peaks and valleys of the ocean floor – a trench as deep as 122
meters (400 feet), followed by a reduction in water depth to 36 meters
(119 feet) and again followed by a depth of over 107 meters (350 feet).
The current of inflowing tributaries within the Passamaquoddy Bay add to
the already busy waters.
Old Sow is reported
to be most active about 3 hours before high tide. This activity
continues for about two hours and takes the form of a collection of
small gyres, troughs, spouts and holes and on the rare occasion will
form one large funnel. This area, which has been reported to be as wide
as 76 meters (250 feet) in diameter, can best be described as turbulent
water. However, during spring tides (high water tide caused by a full or
new moon) combined with high winds or a tidal surge will increase Old
Sow’s activity causing more intense funnels and formations.
Tidal electrical power generation
Several
proposals to build tidal harnesses for electrical power generation have
been put forward in recent decades. Such proposals have mainly involved
building barrages which effectively dam off a smaller arm of the bay and
extract power from water flowing through them.
One such
facility exists, the Annapolis Royal Generating Station consists of a
dam and 18-MW power house on the
Annapolis River at
Annapolis Royal, Nova Scotia, but larger proposals have been held
back by a number of factors, including environmental concerns. The
Annapolis Royal Generating Station has been studied for its various
effects, including an accelerated shoreline erosion problem on the
historic waterfront of the town of Annapolis Royal, as well as increased
siltation and heavy metal and pesticide contamination upstream due to
lack of regular river/tidal flushing. There have also been instances
where large marine mammals such as whales have become trapped in the
head pond after transiting the sluice gates during slack tide.
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