Natural Disasters Project Global Geography 12

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Natural Disasters ProjectGlobal Geography 12
Tsunamis
Project Done by Chris Currie and Josh Lewis May
5, 2003
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One natural disaster that rarely leaves anyone to
recount the story is Tsunamis. Probably one of
the most devastating and destructive natural
forces on the planet. For thousands of years
Tsunamis have struck innocent coastal cities and
villages laying waste to countless kilometers of
land, and taking away innocent lives. In
geography studying the processes on Earth and to
understand everything that happens, both above
and below the surface is the goal, and within the
pages of this report, it is hoped that some light
is shed upon this fascinating and deadly natural
disaster.
Introduction
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Basic Background
The word Tsunami comes from Japanese language and
means harbor wave in English. This is an
accurate description because Tsunamis strike
coastal villages, bays, and harbors. Basically a
tsunami is a huge wave that originates in deep
water. An event that alters the equilibrium of
the ocean surface sends small waves outward.
These waves are small at first but contain a
large amount of water and when they finally reach
the coast they are gigantic walls of water
sweeping away anything and everything in its
path. In the past people have called Tsunamis
tidal waves this is not true for this natural
disaster has nothing to do with the tide. Tides
are controlled by the gravitational forces of the
sun, moon, and the planets. Also Tsunamis have
been called seismic waves this is sometimes
true but not all Tsunamis are caused by
underwater earthquakes but by other means which
will be discussed later.
Japanese Form of Tsunami
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Ring of Fire
The ring of fire is the region basically
surrounding the Pacific Ocean and is also
commonly called the pacific basin. Tsunamis
generally occur within this zone as well as
earthquakes volcanoes and other seismic
activities. In this 32 000 km long area are
oceanic plates that slip and slide underneath the
continental plates the result is often felt as an
earthquake or tsunami. Past Tsunamis have struck
coastal cities along the ring of fire and created
devastating damage, for example in 1996 Peru was
hit, and in 1998 Papua New Guinea. When Tsunamis
occur is beyond the capability of scientists to
predict but going by Tsunamis from the past
scientists can get an idea of certain hotspots
for Tsunami activity and always be on guard with
warning systems.
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The Awesome Power!
Tsunamis have very small beginnings, and yet when
they reach shore become such forces of
destruction and mayhem. A tsunami can be created
in a variety of ways, but basically any event
that disables the equilibrium of the oceans
surface whether it be caused by underwater
earthquakes, landslides, or volcanoes or be even
caused by large meteors. When a tsunami is
formed an upheaval of water is sent to the
surface and in an effort to stabilize the oceanic
equilibrium smaller waves begin to spread
outward. Ships at sea cannot even tell these
waves are out of the ordinary and it passes them
unaffected. But when these waves reach the coast
and begin to come upon shallow water they begin
to increase in size, as the water depth grows
shallower and the tsunami slows down however when
this happens the waves begin to pile up on
another and they carry a huge amount of water.
Water from the coast is sucked into the ocean
much like the tide, probably where the misleading
tidal wave had come from, and to a unlucky
person viewing this event it would seem as if a
huge wall of water were rushing forward until it
comes crashing downward, upon the land washing
away sand, stone, soil, buildings, and people.
Often times a tsunami is followed by several
smaller tsunamis but the first one when it
reaches shallow water can reach up to thirty feet
high and can travel 725-800 km per hour.
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Brief Overview of how Tsunamis are Created
The three basic steps of Tsunamis 1 A
disturbance disrupts the ocean floor and sends a
huge mound of water upward. 2. Waves travel
outward in an attempt to stabilize the oceans
equilibrium. 3. When the waves reach shallow
water they begin to slow and pile up on each
other, creating a massive wall of water and
striking the coast with tremendous force.
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Prevention
With large forces traveling at such high speeds,
a tsunami could travel from Peru to Japan in a
matter of twenty-one hours, these natural
disasters are some of the fastest moving things
on the planet, so it seems a reasonable
precaution to have warning systems in place.
Tsunami Warning System in the Pacific is one and
is in place to try and detect underwater
earthquakes and notify the public before
casualties are sustained, two centers of this
system include one in Alaska and one in Hawaii
two hotspots for tsunami activity. Seismic
activity, though not always relevant to tsunamis,
can be picked up by seismographs to help aid in
the speed and origin of the tsunami.
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Conclusion
In an overview Tsunamis are dangerous, geological
nightmares. Along with their counterpart,
earthquakes, tsunamis can lay waste to kilometer
after kilometer of coastal regions. While they
have humble beginnings started by a earthquake
miles beneath the calm surface of the ocean, the
devastating reach of this natural disaster moves
quickly and packs a heavy punch. Thousands of
lives have been lost because of tsunamis but we
as scientists are learning, day by day, tsunami
by tsunami, and soon we will have protection
against this mighty force. But here is the
question, now that so light has been shed on
Tsunamis, are you living near the coast?
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Bibliography

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