deepanshu melana 2008je0311 19 aug 2009 · what is a tsunami? a japanese word represented by two...

Deepanshu Melana2008JE0311

19 AUG 20091

Contents What is Tsunami?CausesEnergy and speed of TsunamiTsunami’s generationThe Indian ocean tsunamiTsunami warning system

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What is a Tsunami?A Japanese word represented by two words tsu & nami tsu means harbor & nami means wave

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DefinitionA tsunami is a series of ocean waves of extremely long wave length and long period generated in a body of water by an impulsive disturbance that displaces the water.

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CausesEarthquakeLandslideVolcanic EruptionSpace born objects {such as meteorites,

asteroids and comets }

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Scientific Term

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Difference between tsunami wavesand wind waves

TSUNAMI WAVES WIND WAVES

Mainly caused by earthquakeWavelength 60-300 milesTime period 5-60 minutSpeed of 450-650 mph

Caused by windWavelength 300-600 ftTime period 5-20 secondsSpeed of 10-20 mph

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Calculating the Tsunami wave speed

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Tsunami’s GenerationInitiation

Split

Amplification

Run up 11

1. Initiation

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The potential energy that results from pushing water above mean sea level is then transferred to horizontal propagation of the tsunami wave i.e. kinetic energy

2. Split

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The initial tsunami is split into a tsunami that travels out to the deep ocean (distant tsunami) and another tsunami that travels towards the nearby coast (local tsunami)

3. Amplification

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When tsunami waves travels over the continental slope,Its amplitude increases. In addition wavelength decreases.

4. Run up

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

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IntroductionMost destructive tsunami everEarthquake in Indian Ocean of

magnitude 9.3Killed more than 300,000 peopleDisplaced 1.6 million peopleHit India, Thailand, Malaysia,

Indonesia, many Islands, and AfricaEarthquake in Indian Ocean of

magnitude 9.0Rupture was ~1000 miles long

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The Rupture ProcessStarted at 00 hours 58 minute 47 second

GMTTotal area rupture is 250,000 km2

Average deformation is 10 mt.Epic center 3.298 N latitude 95.779 E longitude

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Energy of earthquake2nd largest earthquakeMoment magnitude of 9.3Energy release is around 4.3 x 1018

joules

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Energy of tsunami• 8000 km3 water displaced• Energy of this tsunami is 4.5 megatons of TNT

Reasons for great loss of lifea) Lack of public awareness

b) High population density

c) Lack of an early warning system

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No Tsunami Warning System Exists For The Indian ocean!!

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Methodologies for TsunamiwarningTide gaugesRRTRD (remotely reporting tsunami run-up detectors)

DART system Satellites Animals

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A DART system consists of a seafloor bottom pressure recording (BPR) system capable of detecting tsunamis as small as 1 cm, and a moored surface buoy for real-time communications. An acoustic link is used to transmit data from the BPR on the seafloor to the surface buoy. The data are then relayed via a GOES satellite link to ground stations, which demodulate the signals for immediate dissemination to NOAA's Tsunami Warning Centers and PMEL.

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DART System

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DART Program

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Satellite warning

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