TSUNAMI

# “TSU” MEANS HARBOUR AND “NAMI” MEANS WAVE.

TSUNAMI = HARBOUR + WAVE.

# Tsunami is a series of waves with extremely long wave length and long period generated when a body of water rapidly displace.

# Tsunami is not a tidal wave because the tides are the result of gravitational influences of the moon, sun and planets.

DEFINITION

# Earthquake# mass movements above or below water# some volcanic eruptions# Underwater explosions# Landslides# Large asteroid impact.

CAUSES OF TSUNAMI

CHARACTERISTICS

# Tsunamis are shallow-water waves, which means the ratio between the water depth and water length is very small.

# “NO WARNING!!”, “NO PREDICTIONS”

# Earthquakes are often a cause of tsunami.

# IF the part of tsunami to reach land is trough (draw back) rather than a crest of the wave, the water along the shoreline may recede dramatically, exposing areas that are normally always submerged.

SIGNS OF AN APPROACHING TSUNAMIS.

WARNING AND PREVENTION# BOTTOM PRESSURE

SENSORS.

These are anchored and attached to buoys. Sensors on the equipment constantly monitor the pressure of the overlying water column.

GENERATION OF TSUNAMI

Earthquake

Water column up and down

Potential energy

Kinetic energy

Tsunami

Initial tsunami

Distance Local

Height above mean sea level is the half of the original tsunami.

# Increases and wave length decreases.

This result in steepening of the leading wave.

# Deep ocean tsunami has traveled much faster than the local tsunami because of the propagation speed.

# Run up is a measurement of the height of the water onshore observed above a reference sea level.

# The first run up of a tsunami is often not a largest.

# Tsunamis are not rare, with at least 25 tsunami occurring in the last century.

# Many tsunamis were recorded in the Asia-Pacific region-particularly Japan.

# The boxing day tsunami (Indian ocean tsunami) in 2004 caused approximately 350,000 deaths and many more injuries.

TSUNAMI IN HISTORY

# It was an undersea earthquake.# Occurred on December 26, 2004 of magnitude

9.3 with an epicentre off the west cost of Sumatra, Indonesia.

#Second deadliest earthquake of all time observed up to 10 minutes #US Geological Survey recorded the toll as

283,100 killed ,14100 missing, and 1,126,900 people displaced

Countries affected:-Indonesia,Srilanka,Bangladesh,India,Malaysia,Myanmar,Singapore,Maldives

2004 INDIAN OCEAN TSUNAMI

MALDIVES

INDONESIA

THAILANDSRI LANKA

EPICENTRE AT SUMATRA,INDONESIA

CHARECTERISTICS

#The sudden vertical rise of the seabed during earthquake displaced massive volumes of water

#Tsunami wave height in shallow water near coastline:-24 to 30 meter and in deep water the maximum height was 2 foot

Tectonic Plate #994 miles of fault line

slipped about 50 foot along the subduction zone

#Indian Plate slides under the Berma Plate #Energy released on the

earth surface was 1.1*10^17 joules or 26.3 megatons(equivalent to 1502 times of the Hiroshima atomic bomb)

IMPACTS OF 2004 TSUNAMI

-Loss of human life -shortage of food and

drinking water -damage of the

infrastructure -spreading of diseases -economic damage such as

fishing business, tourism, shipping

-environmental impact for many years on ground water , soil and ecosystem

HELPLESS AGAINST TSUNAMI!!!