TSUNAMI - types, causes, impacts, events

The slide explains about the natural disaster tsunami, its types, its causes and impacts, and the events

1. KEERTHANA G NAVYA NAVEEN S8A
TSUNAMI

2. TSUNAMI
Tsunamis are giant waves caused by earthquakes or
volcanic eruptions under the sea.
-National Ocean Service

A tsunami is a series of extremely long waves caused by a
large and sudden displacement of the ocean, usually the
result of an earthquake below or near the ocean floor.
-National Oceanic and Atmospheric
Administration (NOAA)

Tsunamis are giant waves that are produced when a large
volume of water is displaced in an ocean or large lake by an
earthquake, volcanic eruption, underwater landslide or
meteorite.
-World Health Organisation (WHO)

A series of travelling waves of extremely long length and
period, usually generated by disturbances associated with
earthquakes occurring below or near the ocean floor.
-Intergovernmental Oceanographic Commission
(of UNESCO )

3. HOW A TSUNAMI HAPPEN?
An event displaces a
large volume of
water
Waves reach shore,
often with little
warning.
Waves move
outward in all
directions at speeds
up to 500 mph
Waves gain height as
they approach
shallow water.
1.Initiation: Geological
activity displaces a large
volume of water.
2.Propagation: The waves
move outward in all
directions from the
point of origin.
3.Amplification: As the
tsunami approaches
shallower waters, it
gains height.
4.Impact: The waves
reach the shore, often
with little warning,
causing destruction.

4. TYPES OF TSUNAMI
01

5. Local tsunami
A local tsunami is generated very
close to the coast, typically within
100 kilometers. These tsunamis
are often caused by undersea
earthquakes or landslides and can
strike within minutes of the
triggering event. Due to the short
warning time, local tsunamis can
be particularly dangerous.
TYPES OF TSUNAMI
A distant tsunami travels the
farthest distance of all, exceeding
1,000 kilometers from its source
and potentially across entire
ocean basins. These tsunamis are
often caused by powerful
earthquakes and can take several
hours to reach distant shores.
Regional tsunami Distant tsunami
A regional tsunami travels a
farther distance than a local
tsunami, typically between 100
and 1,000 kilometers from its
source. These tsunamis can be
caused by similar events as local
tsunamis and can reach
coastlines within one to three
hours.
Depending on the source of the trigger and the distance they travel.

6. EVENTS
02

7. EVENTS
Indian Ocean, 2004: One of the deadliest natural disasters in recorded
history, this tsunami was triggered by a massive undersea earthquake
off the coast of Sumatra, Indonesia. It resulted in over 230,000 deaths
across 14 countries, including Thailand, Sri Lanka, and India.

Tohoku, Japan, 2011 : Triggered by a 9.0-magnitude earthquake,
this tsunami led to the Fukushima nuclear disaster. Nearly 16,000
people were killed, and the event had extensive economic
repercussions.
Papua New Guinea, 1998: Caused by an undersea landslide, this
tsunami resulted in waves up to 15 meters high and killed more than
2,200 people.

8. EVENTS
Chile, 1960 : Triggered by the most powerful earthquake ever recorded
(magnitude 9.5), this tsunami affected the entire Pacific, causing deaths as
far away as Hawaii, Japan, and the Philippines.
Lituya Bay, Alaska, 1958 : The highest tsunami wave ever
recorded occurred in Lituya Bay, Alaska, with a wave reaching 1,720
feet. Triggered by a landslide, it had a relatively lower human toll
but showcased the incredible power of tsunamis.
Messina, Italy, 1908: Triggered by an earthquake in the Strait of
Messina, this tsunami killed an estimated 80,000 people in the cities of
Messina and Reggio Calabria.

9. EVENTS
Sanriku, Japan, 1896: Known for its incredibly high run-up heights, the
tsunami resulted from an undersea earthquake and affected the
Sanriku coast of Japan, killing over 22,000 people.

Krakatoa, Indonesia, 1883: The eruption of the Krakatoa volcano
resulted in a tsunami with waves as high as 135 feet. The event
was so powerful that it was heard 3,000 miles away, and it killed
approximately 36,000 people.

Great Lisbon Earthquake and Tsunami, 1755: Occurring on All Saints’
Day, this event devastated Lisbon, Portugal, and affected much of
Europe and North Africa. The tsunami wave traveled as far as the
Caribbean.

10. INDIAN VULNERABILITY
03

11. HIGH RISK AREAS
East Coast and Islands: The Andaman & Nicobar
Islands and the Indian mainland along the Bay of
Bengal are susceptible to tsunamis generated by
earthquakes in the Andaman-Nicobar-Sumatra
subduction zone. The 2004 tsunami tragically
highlighted this vulnerability.
West Coast: Though less common, the west coast
of India can experience tsunamis originating from
the Makran subduction zone in the Arabian Sea.
These events could be particularly dangerous due
to the concentration of population and
infrastructure in this region.



India is considered moderately vulnerable to tsunamis, with some areas at higher risk than others.
INDIAN VULNERABILITY

12. CAUSES
04

13. WHAT CAUSES TSUNAMI?
Thus tsunami warning system primarily depends on
rapid earthquake detection and characterization
The effects of the tsunami on the country during this
period range from destruction and damage, death,
injury, millions of dollars in financial loss, and
long-lasting psychological problems for the
inhabitants of the region.

14. IMPACTS
05

15. ENVIRONMENTAL IMPACTS
Coastal Environment: In the
context of tsunami inundation
and dumping of marine
sediments/pollutants, the
inundated areas viz: beach
ridges/swales, creeks,
backwaters, etc. need to be
studied for the environmental
impacts.
Terrestrial
Environment: The
terrestrial ecosystem along
the coastal zone, which is
inundated by the tsunami,
normally receives the
wastes which got
deposited along with
marine sediments. Hence,
its impacts also warrant
studies to reclaim the soil,
forest, and biomass,
agricultural fields, etc.

16. SOCIAL IMPACTS
Loss of life and property:
Tsunamis can have devastating
effects on life and property. This
major displacement of water is
destroying homes and
infrastructure in the affected
areas. Many people lose their
lives. According to the data,
tsunamis have been responsible
for the loss of more than
430,000 lives since 1850.
Tsunamis cause building
collapses, electrocution, gas
leaks, explosions, tank damage,
and floating debris causing
further injury and death.
Tsunami Damage and Destruction:
tsunami's tidal waves batter the
shoreline and can destroy anything in
their path.This includes boats,
buildings, houses, hotels, cars, trees,
telephone lines—and just about
anything else in their way.
Once the waves have knocked down
infrastructure on the shore, the waves
continue inland for many more miles -
obliterating yet more buildings and
homes. As the water rushes across the
land, it can sweep away yet more trees,
gardens, garages, cars and other
man-made equipment

17. It’s the closest planet to the
Sun and the smallest in the
Solar System
ECONOMICAL IMPACTS
There is immediately a
massive cost when
tsunamis happen.
Rescue teams come into
the area, and victims of
the tsunami need to be
treated.
Governments around the world
may help with the cost of bringing
aid to a tsunami-hit area. There
might also be appeals and
donations from people who have
seen pictures of the area in the
media.

After the initial cost of rescue operations, there is
the clean-up cost. Debris from the destruction
caused by the tsunami needs to be cleaned
away. Damaged buildings that are no longer
structurally safe may need to be knocked down.

18. It’s the closest planet to the
Sun and the smallest in the
Solar System
HOUSING IMPACTS
The housing stock along the
coast, as well as bridges and
roads, suffered extensive
damage. Structures were
damaged by direct pressure
from tsunami waves, and
scouring damage was
induced by the receding
waves. Many of the affected
structures consisted of
nonengineered, poorly
constructed houses
belonging to the fishing
community.

19. Destruction in the Allapad panchayat—a
concrete block house with a reinforced
concrete RC roof photo: A. Sheth.
Scouring in Allapuzha—houses were 4
– 15 m from the shoreline photo: A.
Sheth.
. Damaged house in Edavanakkad
photo: A. Sheth.

20. Thank you!