Tsunamis: More Than a Splash
Presentation By: Ka’ai Young, Ellie Goodrich, Geri Trower,
& Ivan Maurer
PHYSICS 1010
What is a Tsunami?
 A Tsunami is a disastrous wave caused by a disruption on
the Seafloor
 Tsunami is derived from a Japanese word meaning, ‘harbor
wave’: tsu, which means harbor, nami, which means wave
 Most tsunamis are generated by earthquakes, volcanic
eruptions, landslides, and asteroids
Development
 Most tsunamis are initiated by
earthquakes that occur underwater,
but not all of these earthquakes will
produce a tsunami
 Immediately after an underwater
earthquake occurs, the surface of the
sea reflects the new form of the sea
floor, which creates a series of waves
and the start of a tsunami
 http://www.pbs.org/wnet/savageeart
h/animations/tsunami/main.html
Movement & Size
 Tsunami’s usually hit in multiple large
waves, not just one
 Their above water height grows as they
move inland
 Speeds can reach hundreds of miles per
hour.
 http://www.edumediasciences.com/en/a98-tsunami
 A very large tsunami can do some
serious damage even when it occurs
thousands of miles away from where
the earthquake that caused it
originated, although there has never
been one recorded that has gone
farther than a mile inland
Movement and Size
Tsunami Hazards:
Local Tsunami’s
 Locally generated tsunamis have the potential to
reach a nearby shore in the span of 10 minutes
 Not enough time for any tsunami warning center to
issue a tsunami warning
Tsunami Hazards:
Wave Propagation
• Disruption on the seafloor
creates displacement in the
water and Tsunami waves are
formed
• Once they are formed they
move in all directions away
from the origin point
Tsunami Hazards:
How often do they occur?
 In order for an earthquake to cause a
noticeable tsunami it must have a
magnitude of at least 6.75 on the
Richter scale
 Because of this, larger tsunamis only
occur on an average of about 6 per
century with ninety percent of those
occurring in the Pacific Ocean
 There is no way to calculate how
many smaller tsunamis occur because
their effects are rarely noticeable at
all
Prevention
 Tsunamis cannot be prevented
 The damage can be reduced by being rightfully
prepared and educated about these monstrous
waves
 Tsunami walls have also been installed in many
coastal communities to reduce damage
Tracking a Tsunami
 Before the devastating Tsunami of 2004, we don’t
have much ability to track Tsunamis
 Now we can trace the following once a wave has
been detected:




Height
Speed
Arrival Time
Flood potential
Warning Systems
 Deep Ocean Assessment and
Reporting of Tsunamis
(D.A.R.T)
 http://oceantoday.noaa.gov/
trackingtsunamis/
Warning Signs
 Some warning signs include:
 An earthquake or volcanic eruption near a coastal
community
 Shaking of the ground
 Receding of the ocean
 Sound of loud ocean roars
 A noticeable rise or fall in the shore line
 An approaching wall of water
Review
 Named by the Japanese, caused by volcanic eruptions,
earthquakes, landslides, and asteroids
 Created by sudden events that displaces the sea floor, which
then causes the sea to compensate for that displacement of
water
 Not noticeable until it reaches closer to shore
 Multiple waves; first wave isn’t always the most dangerous
 Locally generated waves are dangerous
 Natural phenomenon, cannot be prevented
 Deep Ocean Assessment and Reporting of Tsunamis (D.A.R.T)
 Receding of the ocean is one major sign