3. Tsunami, Japanese word meaning “harbor wave,” used as
the scientific term for a class of abnormal sea wave that can
cause catastrophic damage when it hits a coastline.
Tsunamis can be generated by an undersea earthquake, an
undersea landslide, the eruption of an undersea volcano, or
by the force of an asteroid crashing into the ocean. The
most frequent cause of tsunamis is an undersea
earthquake. When the ocean floor is uplifted or offset
during an earthquake, a set of waves is created similar to
the concentric waves generated by an object dropped into
the water. Most tsunamis originate along the Ring of Fire, a
zone of volcanoes and seismic activity, 32,500 km (24,000
mi) long, which encircles the Pacific Ocean. Since 1819,
about 40 tsunamis have struck the Hawaiian
4. MAJOR TSUNAMI DISASTER
The worst tsunami disaster in history
occurred in December 2004 when a
magnitude 9.0 undersea earthquake,
centered in the Indian Ocean off the
northwestern coast of the Indonesian island
of Sumatra, generated a tsunami that struck
the coasts of 14 countries from Southeast
Asia to northeastern Africa. The
International Committee of the Red Cross
reported a death toll of more than 250,000
people as a result of the tsunami and the
earthquake, with nearly two-thirds of the
deaths occurring in Indonesia. High death
tolls were also reported in India, Sri Lanka,
and Thailand. Geologists calculated that the
ocean floor at the epicenter was thrust
upward 9 m (30 ft) as a result of the quake
5. In North America the worst known tsunami
occurred in 1964 when an earthquake off
the coast of Anchorage, Alaska, created a
tsunami that killed 115 people in Alaska,
Oregon, and California. Scientists also
believe that a magnitude 9.0 quake
occurred along the Cascadia fault off the
coast of Washington and Oregon in 1700 and
generated a massive tsunami. Scientists
believe the quake and tsunami converted
vast spruce tree forests into saltwater
tidal flats.
6. TSUNAMI HITS THAILAND
Ocean water submerges
coastal buildings on
Thailand’s Phi Phi Island
after the worst tsunami in
history killed people in 14
countries rimming the Indian
Ocean in December 2004.
The death toll reached more
than 250,000 people. It far
eclipsed the death toll
caused by the second worst
tsunami, which destroyed
Lisbon, Portugal, in 1755
and killed 60,000 people.
7. TSUNAMI DISASTER OF 2004
On December 26, 2004, the world’s most powerful earthquake in 40
years struck deep under the Indian Ocean. The magnitude 9.0
earthquake was centered off the northwestern coast of the Indonesian
island of Sumatra. The earthquake triggered a tsunami (massive
waves), which spread across the Indian Ocean and crashed into the
coasts of 14 countries from Southeast Asia to the eastern coast of
Africa. Killer waves hit the coast of Sri Lanka about two hours after
the quake. Due to the absence of a tsunami early warning system in the
Indian Ocean, coastal communities in the region were not forewarned
of the impending disaster.
The tsunami was the deadliest in recorded history. The International
Committee of the Red Cross reported a death toll of more than 250,000
people as a result of the tsunami and the earthquake. Indonesia,
nearest the epicenter of the quake, suffered the largest loss of life. Sri
Lanka was the second hardest-hit country, with more than 30,000
people reported dead or missing
