abstract

“The ways in Reducing the Number of Victims

if Tsunami Occurs”

BY: Suparno and Wiwi Rosaria

Abstract

The purpose of this presentation is to explain about the ways that can be implemented in reducing the number of victims if tsunami occurs in the areas that have potential to be attacked by such extraordinary wave known as tsunami . Many countries in this globe have a history of producing earthquakes that triggered tsunamis and thousands of people became the victims. Therefore, this case triggers us to think deeply about the solution about the ways that can be implemented to reduce the number of victims if tsunami occurs. Actually, there are several ways that can be done to reduce the number of victims if tsunami occurs in the FUTURE.

Introduction

A tsunami is a very long-wavelength wave of water that is generated by sudden displacement of the seafloor or disruption of any body of standing water. Tsunami are sometimes called "seismic sea waves", although, as we will see, they can be generated by mechanisms other than earthquakes.

Tsunamis that strike coastal locations in the Pacific Ocean Basin are almost always caused by earthquakes. These earthquakes might occur far away or near where you live. The force of some tsunamis is enormous. Large rocks weighing several tons, along with boats and other debris, can be moved inland hundreds of meters by tsunami wave activity, and homes and buildings destroyed. All this material and water move with great force, and can kill or injure people. Their height can be as great as 10 m or more (30 m in extreme cases), and they can move inland several hundred meters. All low lying coastal areas can be struck by tsunamis. A tsunami consists of a series of waves with crests arriving every 10 to 60 minutes. Often the first wave may not be the largest. The danger from a tsunami can last for several hours after the arrival of the first wave. Tsunami waves typically do not curl and break, so do not try to surf a tsunami! Tsunamis can move faster than a person can run. Sometimes a tsunami initially causes the water near shore to recede, exposing the ocean floor. Tsunamis can occur at any time, day or night.

All types of waves, including tsunami, have a wavelength, a wave height, an amplitude, a frequency or period, and a velocity.

Wavelength is defined as the distance between two identical points on a wave (i.e. between wave crests or wave troughs). Normal ocean waves have wavelengths of about 100 meters. Tsunami have much longer wavelengths, usually measured in kilometers and up to 500 kilometers.

Wave height refers to the distance between the trough of the wave and the crest or peak of the wave. Wave amplitude - refers to the height of the wave above the still water line, usually this is equal to 1/2 the wave height. Tsunami can have variable wave height and amplitude that depends on water depth as we shall see in a moment Wave frequency or period - is the amount of time it takes for one full wavelength to pass a stationary point. Wave velocity is the speed of the wave. Velocities of normal ocean waves are about 90 km/hr while tsunami have velocities up to 950 km/hr (about as fast as jet airplanes), and thus move much more rapidly across ocean basins. The velocity of any wave is equal to the wavelength divided by the wave period.

Tsunamis Disaster

Naturally, there are many areas that have potential to be struck by a giant sea wave or tsunami that had shown its power in devastating the islands in our beloved planet “Earth”. Actually, there are several areas in this world that can be attacked by tsunami such as Indonesia, Japan,, Srilangka, and the other areas that are situated in a Ring of Fire, have tectonic plate and fault lines. Moreover, many people live in coastal areas, and it’s hard to relocate or ask them to move from these areas because of various reliable reasons such as the location of their livelihood, the places where they were born, and many more acceptable reasons.

It still remind fresh in our mind about the terrible day on December 26, 2004. A magnitude 9,3 earthquake struck Sumatra islands, exactly in Aceh Island. . The tsunami which was generated by earthquake, devastated nearby areas where the wave may have been as high as 25 meters (80 feet) tall and killed nearly 300,000 people. The earthquake resulted from complex slip on the fault where the oceanic portion of the Indian Plate slides under Sumatra, part of the Eurasian Plate. The earthquake deformed the ocean floor, pushing the overlying water up into a tsunami. Thousands people were killed and many people suffer various defects. This catastrophe truly gave bad impacts to the people, especially to the survivors of the disaster, because many children lose their mothers, fathers, brothers, sisters, or any relatives that they still need. The survivors also have to lose their own properties, cause financial lose, livelihood, suffer a lot of pain both physically and mentally, become trauma after that disaster, and also the other miseries that’s hard to be depicted which they have burdened after this terrible disaster. Children suffered heavily in the tsunami, accounting for at least one-third of the death toll and losing caregivers, relatives, and homes. But young survivors are seeing some gains in their lives half a year later as they go back to school in the new academic year that began last month. Tsunami-affected school buildings are not only getting repaired, but also spruced up in the tsunami-affected areas.

Actually, such a bad condition would not have happened if we had implemented several ways in reducing the victims and applied sophisticated technologies to predict this disaster.

THE WAYS IN REDUCING THE NUMBER OF VICTIMS IF TSUNAMI OCCURS

What to do Before and During a Tsunami?

The following are guidelines for what you should do if a tsunami is likely in your area:

l Turn on your radio to learn if there is a tsunami warning if an earthquake occurs and you are in a coastal area. For example, member of the DXpedition, S. Ram Mohan (VU2MYH) established aradio station on Car Nicobar Island, one of the most affected areas. According to ARRL,

“Asian Radio Amateurs Bridging Communication Gap following Tsunami”, the signal

from Mohan’s transmissions were weak. He changed frequencies and resorted to Morse

Code as needed. That station (VU4MYH) was the first amateur radio operation from Car

Nicobar Island, and provided the only communications to the outside world for days.

In fact, what began as a short-term ham radio special event, demonstrated the

enormous importance of ham radio in emergency situations. Telecommunications

equipment was damaged or washed away by the tsunami. The satellite uplink antenna

lost its alignment. The only communication that could function was amateur radio. The

ham radio team provided communication among officials, communication between the islands, and coordination of relief efforts.

l Move inland to higher ground immediately and stay there. Keep calm and quickly away from the coast. All large earthquakes do not cause tsunami, but many do. Safe zones: 30 meters above the sea level if you are on the coast, 4 km away from the beach if the land is flat. If you can't go this far or this high, go as far as you can. Every step up or inland will help you. If you are cut off from higher ground, go to the third floor or higher of a strong building. Even climbing a tree may save your life.

l Stay away from the beach. Never go down to the beach to watch a tsunami come in. If you can see the wave you are too close to escape it.

l CAUTION - If there is noticeable recession in water away from the shoreline, the ocean water draw far down and expose the seafloor, or you hear a loud roar from the coast this is nature's tsunami warning and it should be heeded. You should move away immediately. A tsunami may be coming.

The Government should adopt the following preventive measures :

1. Improve public education and law enforcement efforts to better combat caste- based discriminatory practices. Enhancing public awareness of natural disasters through education is a great importance in minimizing the victims as education plays a key role in preparing people to deal with natural disasters. Policy advice on inclusive education to meet the needs of schoolchildren physically affected by the tsunami. Knowledge saves lives as today many people are not fully aware of hazard risks faced nor of the safety measures and risk reduction measures required. A selection of tools demonstrates how to teach natural disasters and contextualize the recent tsunami for young students. Psycho-social and pedagogical training for teachers and educational professionals is needed
2. Seek to restore a sustainable livelihood for all communities of fishermen by ensuring that fishermen have adequate access to the coastline , and have proper boats and implements necessary to resume their trade
3. Seek to restore a sustainable livelihood for all communities of fishermen by the tsunami; such measures include creating compensation mechanisms that account for non-tangible assets, and providing alternate employment for daily wage laborers in local reconstruction efforts;
4. Encourage cooperation among government officials, nongovernmental organizations and donor agencies to prevent uneven or inefficient distribution of resources.
5. Speedy and immediate measures should be taken to identify the most important and vulnerable areas of the country. the most vulnerable and an important spot struck by tsunami should be completed by many facilities such as the possibility of the Australian plate and euroasia plate coming into collision. It is impossible for scientists to predict when, where and how this plate collision could cause tsunamis, depending on the intensity of the earthquake. It is believed that even a quake measuring over 6 on the Richter Scale can endanger an island.

What facilities should be provided?

There are several facilities that can decrease the victims as described next:

1. Build dikes and place seawalls. Dike is an embankment constructed on dry ground along the beach to prevent overflow of lowlands and to retain floodwater. Seawall is a form of hard coastal defense constructed on the inland part of a coast, The walls can be sloping, vertical or curved to reflect wave power.

2. Make many alternative roads lead to the high areas to enable people reach the high areas in short time without any traffic jam. When fleeing a tsunami caused by a nearby earthquake, you may find roads broken or blocked if there is no alternative road available.

3. Provide disaster preparedness measures in the form of tsunami escape signboards to guide potential victims through an escape route in the event of a similar incident in the future.

4. Plant mangroves greenbelts because mangroves enable to take most of the tsunami energy. So, if tsunami arrive in an island. Its power has decreased, consequently, it won’t be easy for the wave to ram into the breakwaters or seawalls, and the buildings near the coastal areas will not collapse easily. Current efforts to protect people living along South Asian coasts from another devastating tsunami do not necessarily entail high-tech, governmental schemes. In fact, it is now concerned local populations who are getting involved in the conservation of natural buffer zones such as mangroves and sand dunes, which have been shown to absorb much of the damage. So, Nature is Our Best Ally to Avoid Future Tragedies

Natural Disaster Board

To reduce the victims, the government also can establish Natural Disaster Board. This Board will have responsibility to

a. Get the latest information about their area.
b. Increase society knowledge about natural disasters through any kinds of socializations.

This can be done by delivering pamphlets, publishing the topics dealt with natural

disaster on the mass medias, producing documentary films, etc.
c. give simulation to the society if a natural disaster occur. Like in Padang the government

held tsunami simulation by asking the people to run to the higher areas such as tall

buildings and hills
d. Ask people to keep protecting our environment from any destruction. We should prevent

the sea by letting the mangroves or any trees keep living there.
e. Ask people to built the house far from the beach or on the high area, and it should be

earthquake-resistant as well
f. Improve preparedness to save the people, and the police, firehouse and the ambulance

have to be prepared to help in emergency.
g. Increase disaster budget in order to the programs related to the disaster
can work smoothly.

We can also provide several instruments and methods to warm the people like:

1. Tsunami-Warning System. the technological equipment placed at the bottom of the sea,

near the fault line. This equipment sends the signal of prediction to BMG.

2. Satellites are also used in a similar detection system based on global positioning

system (GPS) navigation satellites that also monitors the vertical motion of waves

but this time via static buoys moored out in the ocean. At Tokyo University’s

Earthquake Research Institutes (ERI) a network containing 24 GPS satellites has

been designed and implemented so that buoys signals from the sea surface can be

picked up by at least three of the satellites at any given time.

3. Combined, measurement and modeling techniques can provide reliable

tsunami forecasts.

To forecast inundation from early tsunami waves, seismic parameter estimates and

tsunami measurements are used to sift through a pre-computed

generation/propagation forecast database and select an appropriate (linear)

combination of scenarios that most closely matches the observational data. This

produces estimates of tsunami characteristics in deep water which can then be used

as initial conditions for a site-specific (non-linear) inundation algorithm. A statistical

methodology has been developed to forecast the maximum height of later tsunami

waves that can threaten rescue and recovery operations. The results are made

available through a user-friendly interface to aid hazard assessment and decision

making by emergency managers. The MOST model performed computations of

generation/propagation scenarios for the forecast database. The nonlinear high-

resolution model will provide the inundation forecasts. This methodology is the

foundation of the next generation forecast tools for tsunami warning and mitigation

that are being developed in close collaboration with Tsunami Warning Centers and

academia. These new tools will provide site- and event-specific forecast of tsunami

amplitudes to assist emergency managers during tsunami warning and mitigation

4.The input parameters for the MOST model of tsunami propagation and run-up and
The input parameters for the MOST (Method of Splitting Tsunami) model can be set in several ways that depend on the application. The location and magnitude of the earthquake are used in a ground deformation model to estimate the vertical displacement of the ocean floor. This displacement is set to the initial displacement of the sea surface, which is then the initial condition for the tsunami wave in the MOST model. This is how it is run in a research mode. A set of earthquakes is used in doing a tsunami risk assessment for communities, including the maximum credible event for designing evacuation strategies. Operationally during a possible tsunami event, a sequence of different MOST simulations is run (more exactly: scaled from a pre-computed database of MOST model runs) as new information about the earthquake and tsunami become available. The first set is obtained from the earthquake alone. This process has been incorporated into the first version of the SIFT tsunami forecasting system that is being delivered to the U.S. Tsunami Warning Centers this Spring.Once actual observations of the tsunami become available at DART buoy stations, the tsunami source (and hence the earthquake parameters) are adjusted to match the observed tsunami. These new parameters are then used to make updated coastal tsunami forecasts for potential impact sites. This system under development will include the capability to run standby inundation models (SIMs, essentially high-resolution MOST models optimized for computation speed) for selected coastal communities, in order to get the best quality forecasts at those sites. This new version of SIFT will be delivered to the Warning Centers within a year from now.

Conclusion

So, it’s obvious that inherently we can minimize the effects of disaster, particularly tsunami. By implementing several ways that have been presented before, it is hoped that the victims can be decreased, or there will be no people die. Naturally, there are still many ways that we can do regarding to the solutions of the natural disaster like tsunamis, which have resulted a lot of pains or sufferings for human beings. Therefore, the best way to face such bad situation is by preparing our selves both physically and mentally. And don’t forget to keep praying to the God!

REFERENCES:

1. http://www.fema.gov/hazard/tsunami/ts_before.shtm
2. http://nctr.pmel.noaa.gov/tsunami-forecast.html
3. http://pubs.usgs.gov/circ/c1187/
4. http://space.about.com/library/weekly/blindonesiatsunami.htm
5. http://www.treehugger.com/files/2005/12/tsunami_trees_t.php

Attachment 1

PICTURES OF TSUNAMI

Destroyed houses in Banda Aceh, Sumatra, Indonesia

Destroyed houses in Banda Aceh, Sumatra, Indonesia

Northern shore of Banda Aceh, Sumatra, Indonesia.
Top picture: June 23, 2004
Bottom picture: December 28, 2004
(Two days after the tsunami)

From green to brown -- the land is gutted
Aerial view of Banda Aceh, Sumatra, Indonesia.
Picture on left: January 10, 2004
Picture on right: December 29, 2004
(Three days after the tsunami)