INTRODUCTION
The Bay of Fundy, which is found off the shores of Nova Scotia, has the highest tides in
the world .
Extraordinary tides occur when the tidal wave length is two to four times the length of
the Bay. By virtue of blind luck or physics, the tide is amplified into a standing wave,
like water sloshing in a bathtub. For a breaking wave to form, the surging tide must meet
an obstacle. When the ocean meets the river going in the opposite direction, the sea
hesitates, piles up behind the front line, and advances anew in a tidal bore.
Usually the ingredients occur during a new moon with 15 feet tides and the opposing
force of the Shubenacadie river to display the true Bay's magnificence.
This part of St. John is divided into 3 main areas: the main Harbor, Courtenay Bay and
the Outer Harbor. These areas are influenced by the Bay of Fundy tides and the currents
of the St John River which flow out of the main Habour into the Bay.
This section also experiences two high and two low tides each day (semi - diurnal), with
a tidal range varying from 15 to 18 feet, depending on the type of tides. High - water
heights vary from 22 to 28 feet and low - water heights vary from 0 to 7 feet above chart
data. Because of these semi - diurnal tides and the action of the St John River, slack
water in the Habour occurs at approximately tides and not at high or low water as would
be the case at other parts.
THE RHYTHMIC RISE AND FALL
In the Bay of Fundy, the tides are spectacularly large. While the rise and fall of sea
level due to tides is the most apparent aspect, it is also the tidal currents that direct
magnification of tides, and the sea level rises or declines are due to resulting
convergences and divergencies. These tides rise and fall over a range that is greater
than 50 feet; such massive water movement combined with accumulation of sediment through
erosion has built up a large salt marsh that is a feeding station for migrating shore
birds. The low fundy also feeding a ground for marine life including whales. A long time
ago between about 15000 and 10000 year ago at the glacier retreated from the last ice
age, part of Georges Bank were dry land. Such as fragment of trees and mammoth teeth from
this are still found occasional in fishing travels. The sun and the moon are the only
important celestial bodies in producing Terrestrial tides. While the moon is much smaller
than the sun, it is nevertheless more important for tidal processes, because of its
proximity to the earth. There is a small imbalance between the centrifugal force and the
gravitational attraction of the moon on the water column that gives rise to horizontal
forces, causing water motion that causes two bulges in the sea surface. One immediately
under the earth, and the other on the other side of the earth. These bulges tend to
rotate around the globe along with the moon resetting in semi-diurnal tides with a period
of half a lunar day (12.4 diurnal hours) even though the earth's rotation is a diurnal
period of 24 hours.
PROLOGUE
The Bay of Fundy is an area of about 1.6(100000 Km2).
The Bay of Fundy is a part of the Continental Shelf off eastern Canada and New England.
It also serves as an extension that divides New Brunswick from Western Nova Scotia. At
the Bay of Fundy's tidal river at the Southwestern tip of Nova Scotia, sea water
overflows the other riverbank in spring to deposit loads of North Atlantic Salt twice
daily. In the tidal river, fresh water and salt water are mixed. Fundy of Bay is famous
for its tides which is the best and highest in the whole world. The marsh is a home to
mammals, a breeding place for birds and a feeding ground for estuary fish. It is a land
that leaves even the most experienced naturalists awestruck by the aerial ballet
performed annually by thousands of birds flying wing to wing during annual migration.
The first experiment dealing with the consequences of environmental pollution was
conducted at Yarmouth. There was a polluted brook on a farm sullied by foul-smelling
effluent. Part of problem came from the regional airport where noxious run of f had
spilled into the head water of the brook. This pollution stayed in the brook for over 25
years. The area was putrid smelling from fish meal and made people sick.
TIDAL POWER
The Fundy tides are a renewable source of energy with potentially hundreds of billions of
kilowatts generated each year. It has the potential to provide viable energy, as there
is a growing need for pollution-free sources. The Bay of Fundy tidal power has, over
half a century, been sparked interest and successful investigation into the potential of
its development. Technological advancement and "the new economy"brought renewed interest
into developing energy from the Fundy tides.
SUN AND MOON
While the rhythmic modulation of sea level and its association with the motion of the sun
and the moon must have been noticed since prehistoric time, a better understanding had to
wait until Sir Isacc Newton applied his theory of gravitation to explain the underlying
physical mechanism. He was able to construction an equilibrium theory of tides, that
explained the semi-diurnal nature of tides in most parts of the world. If there were
infinite time allowed for adjustment of the ocean to the astronomical forces it is the
equilibrium tides that would be the result. This is, however, not the case since the
tidal forcing varies quite rapidly with time. Resonance in the oceanic response push
tides in certain localities to be above the value predicted by the equilibrium theory.
While the equilibrium theory products two bulges to form, one underneath the moon and the
other on the opposite side of the globe, in reality the high water may significantly
precede or lag the transit of the moon. These differences are due to the dynamic response
of the oceans to tidal forcing. It was Laplace who a century later laid the theoretical
and mathematical foundation for modern dynamic theory of ocean tides by considering
oceanic tides to be the response of a fluid medium to the astronomical forcing by the sun
and moon's gravitational attractions.
THE OIL OF FUNDY BAY
The transportation of oil from the Bay of Fundy and the generation of nuclear power are
two aspects of the same issue in that the supply of energy that present inherent risks to
the environment, but opposing arguments against the use of foreign oil and nuclear power
might be base on purely economic grounds. The risk of oil spills with catastrophic and
long lasting effects on Marine organisms and the coastal environment is always a
possibility.
TIDAL POWER OF ELECTRICAL ENERGY
The monumental Mains Basin scheme produces more than twice as much electricity in Nova
Scotia at 4560 megawatts from all sources-coal, oil and hydro as the largest water-driven
electrical power plant in the world. Nova Scotia produces more power than Newfoundland's
Churchill Falls (about 2660 megawatts) and Ontario Hydro's Picketing nuclear-power plant
( 2160 megawatts). Tidal power would not replace conventional electrical energy derived
from nuclear or fossil fuels for peak demand. Tidal power has fluctuating peaks so. At 12
noon is when you need the power might not be quailabler. Utilities would still meet peak
demand whether or not tidal power was on the line. The renewable energy source using
lunar gravitation and hydroelectricity has become increasingly important. Compared with a
river dam, tidal power has a difficult saltwater environment, where machines are needed
to produce of power and also have saltwater durability. The electric power output is the
twice-daily ebb average of tidal electricity less than 40% of the generating capacity of
a river dam.
TIDAL POWER AND THE MILL
In the 15 century, a construction handbook was published ,showing how tidal water was
held behind a dam at high tide so that when a sufficient water level was reached between
the land and sea sides of the dam . a mill could use tidal water to mix with the fresh
water to turn the waterwheel that provided power for grinding grain. The first mill in
the would was built in 1607 by Samuel de Champlain on the Lequille River. By 1910
Turnbull and an American engineer, designed a double basin scheme that would cross the
international boundary between New Brunswick and Maine.
CONCLUSION
Given the grave environmental challenges such as global warning or environmental
pollution facing many kind in the coming century and because oceans play such a very
important role in governing the degree of global warming, fisheries yield, and degrees of
pollution along our beaches, the study of the tides through a variety of means such as
ship surveys, and remote sensing will lead to a better understanding of how the oceans
work. The hope is that as a result, we will leave behind for our children a world that is
both livable as well as enjoyable in all its majesty . If we an avoid oil spills into the
ocean the water and environment will be more beautiful and ecologically safe for all
living things.
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