Lessons from the 2004 Indian Ocean tsunami: the danger is not over. NaMo, create United Indian Ocean States

LIKE electronic tentacles, they sit anchored to the ocean floor kilometres below the surface, constantly measuring the vast volume of water around them for pressure changes that could indicate the build up of a tsunami.

The data is relayed by acoustic telemetry – coded bleeps – to buoys bobbing on the surface, which in turn relay the information to a satellite. Ten operational Deep-ocean Assessment and Reporting of Tsunamis (Dart) buoys are deployed in the Indian Ocean.

But as memories of that disaster that killed almost 250,000 people across coastal Asia fade, experts warn against complacency – among both the residents at risk and at the highest level of governments. Political will and financial commitment remain a must to keep the system running and, undoubtedly, save lives in the event of another major tsunami.

Within minutes of the data being received at the RTSPs, the conclusions are sent to other national centres at the edge of the Indian ocean. These in turn trigger a chain of “tsunami watch” or “tsunami warning” messages, if warranted, to local authorities, agencies like the police, coast guard and the fire department, the media, and finally local non-governmental organisations (NGOs) and community leaders.

Speed is of the essence to save lives. The target time, from detecting an earthquake and a tsunami and getting a warning out from the RTSPs, is 10 minutes. Then it is up to the national systems in individual countries to issue tsunami warnings.

“Forecast and warning is only one component of the warning system,” says Seattle-based Dr Vasily Titov, chief scientist at the US National Oceanic and Atmospheric Administration (NOAA) Centre for Tsunami Research.

“If there is a warning but people don’t know what to do, then the warning doesn’t work. If people know what to do but there is no warning, it doesn’t work.”

In Thailand, technicians at the National Disaster Warning Centre (NDWC) in one room in Bangkok override and interrupt ongoing TV and radio programming, call key government departments and local town authorities through hotlines and send out thousands of text messages to mobile phones. Finally they trigger warning announcements and sirens at 328 towers along the coast that in 2004 had no such system and was devastated by the Boxing Day tsunami.

The NDWC technicians do twice daily internal drills, and occasionally full-blown tsunami warning drills. Thai beaches are highly developed tourism zones, and the industry is crucial for Thailand’s economy. Beach hotels widely feature tsunami evacuation route signs.

In India, the warning system relies more on swift communication with designated agencies, teams and individuals on the ground mostly on mobile phones. Scientist R. Elangovan, from the M.S. Swaminathan Foundation, is one of many point individuals in the warning network. The foundation installs and runs communications equipment for fishing communities, and disaster warning and response are a part of its remit.

In an interview over a steel tumbler of strong south Indian coffee in the town of Cuddalore – one of the districts worst hit in 2004 – Elangovan says “knowledge workers” and disaster mitigation teams are in place at the village level.

The foundation could send a “voice SMS” or recorded phone message to reach about 7,000 fishermen on their mobile phones virtually simultaneously, from Cuddalore in Tamil Nadu to Kanya Kumari at India’s southernmost tip, he says.

And his own mobile phone is switched on constantly, even at night. “Within five minutes of getting the message from INCOIS (the Indian National Centre for Ocean Information Services) we get the message out to the fishing communities,” he says.

“The Indian Ocean Tsunami Warning System is actually a system of systems,” explains Perth-based Tony Elliott, head of the secretariat of the Intergovernmental Coordination Group for the Indian Ocean Tsunami Warning and Mitigation System (ICG/IOTWS).

“Each country operates its own detection, monitoring and warning systems,” he says.

Elliott describes the data from deep sea sensors and buoys, from the network of 180 seismometers available in real time and from sea level gauges, as the “life blood of the system”.

“The technical challenge is maintaining a highly complex system with many different components,” he says. “Each part of the warning chain is essential. If any link in that chain breaks, then of course the whole system would have failed.”

Scientists have more than 10 years of experience now and have gone through three generations of technology, and are working on a fourth, says Dr Titov in a phone interview from Seattle. “Since 2004, every single tsunami has been detected. Most of the time Dart was the first to detect them. We are confident that the system works pretty well.”

Charitha Pattiaratchi, a professor of coastal oceanography at the University of Western Australia who worked with Dr Titov, was near the beach at Payagala about an hour south of Colombo in his native Sri Lanka, on Dec 26, 2004, and witnessed the tsunami.

“The longer you go without an incident the less people are going to spend money,” he warns. “Maintaining the funding is probably the biggest challenge.”

Tsunami warnings are also a delicate business, he says. “Sri Lanka has taken a safety-first approach, it’s been more liberal with evacuation warnings. Then the question is, if you have too many of these warnings, people may not have confidence in them anymore.”

At the most recent Indian Ocean Wave 2014 tsunami warning exercise in September, based on a simulated powerful earthquake, warnings were transmitted down to the sub-district level in India but not beyond that. That means there were no warnings at the village community level.

But in at least one spot – the waterfront in the former French colonial enclave of Pondicherry – police did arrive about an hour after the alert from the INCOIS and cleared the normally busy promenade of people and traffic.

A couple of hours’ drive south though, on the beach in Nagapattinam district, families played as usual in the surf about 100m away from the imposing, centuries-old Basilica of Our Lady of Health – at the same spot where hundreds died in 2004 as they waited for the Sunday service.

That scene, in which the 2004 disaster is far from the minds of most ordinary people, cannot but underline the critical importance of the tsunami warning system.

Without it there is a danger that the memory will fade. The neglected memorial tower nearby and the granite plaques along the long coast listing the names of the dead will be just signposts – until the next big earthquake below the sea, which is only a matter of time.

PANIC gripped the people of Aceh on April 11, 2012, when an 8.5-magnitude earthquake triggered a 1.02m tsunami in Meulaboh, West Aceh, even though the waves were nowhere near the size of the more than 10m-high waves of Dec 26, 2004.

In fact, the fear was almost as intense as that which overwhelmed residents during the 2004 earthquake and tsunami, and even greater in several areas that had been decimated by the earlier disaster.

The widespread anxiety clearly indicated that Aceh has not learnt lessons from the 2004 tsunami’s destruction. People along the coast fled without any coordination, clogging almost every escape route as they desperately struggled to get away in whatever vehicles were available.

Similarly, many of the rescue workers who should have been helping residents just tried to save themselves without regard for the mass chaos on main roads.

Indeed, the entire standard operating procedure established after the 2004 tsunami failed.

The police and transportation office did not show up at the most critical moment, but only after the end of the “golden time” - the best period to save lives, between the earthquake and the tsunami surge.

Community members and government personnel seemed to have lost the disaster-vigilance skills they have already learned and practised.

The minimum understanding and awareness of disaster handling becomes a tough challenge for all relevant parties, from policy and disaster-warning controllers to post-disaster handling agencies.

Based on a study by the Tsunami Disaster And Mitigation Research Centre (TDMRC) in Banda Aceh, more than 30 disaster-alertness programmes have been implemented by the government as well as by local and international NGOs. It means the public has followed various disaster-risk reduction training courses since 2004.

However, the April 2012 earthquake raised questions about just how effective all these programmes have been.

“Some people promptly took refuge on higher ground, others were observing the seashore first to check if waves have receded, and still others ran in panic as if they hadn’t been prepared to evacuate at all,” says Rina Suryani Okta, a TDMRC researcher.

Public understanding of the early-warning system also varies. Many people think that when tremors occur, a warning system such as sirens will automatically operate.

“They don’t know that sirens need to be manually activated,” she says. “Somebody will push buttons to sound the sirens.”

Indeed, few people know that the warning system comprises several instruments working together to analyse local conditions and finally issue a warning if really necessary.

“Sirens are only one part of the early-warning system,” Rina points out.

There is also a notion that a tsunami will strike after a strong earthquake lasts for a long time. It has been misunderstood that minor tremors cannot cause a tsunami.

“Disaster-risk reduction activists, take note of this misunderstanding to straighten out that misinformation,” says Rina. “A tsunami doesn’t always result from a major quake.”

The TDMRC is striving hard to promote public understanding and its alert level through various means, including research and education provided for several schools to create disaster-vigilant students.

“At present, the TDMRC is undertaking several disaster mitigation and education projects in a number of schools, covering junior and senior high schools around Banda Aceh and Aceh Besar,” says Rina.

The centre is responsible for educating people from early levels of school, while seeking to make the subject of disaster handling an integrated part of school curricula, especially in Aceh.

The centre also attempts to train preachers across villages so as to develop their disaster-mitigation perspectives, and spread knowledge and awareness of disasters at rural religious meetings.

Their lectures will hopefully make village communities realise that a calamity is not something they have to resign themselves to as a divine act. It also involves an awareness that death tolls can be lowered if people know how to deal with and avoid a disaster.

Rina says a tsunami in Japan on March 11, 2011, showed that those who survived were people capable of recognising and perceiving the dangers, vulnerabilities and risks around them. They could therefore decide on the best ways to escape and reduce the number of casualties.

“We don’t evade our destiny or cheat our fate, but at least we’re trying to minimise deaths through disaster-mitigation education for communities living in disaster-prone regions like Aceh,” Rina adds.

People in Aceh still view natural disasters more from the viewpoint of religion than science, so many scientific facts crucial to the promotion of public awareness are ignored.

“Every disaster is God’s will and intervention so that we have no way of avoiding it when it comes,” says Nasrul Ifan from Deah Baro village, Banda Aceh. He survived the 2004 disaster but lost his family before remarrying and continuing to live in the same coastal village.

Nonetheless, coastal residents have begun to develop an awareness of learning from natural signs that may indicate a tsunami. Those living along Aceh’s western coastline can now distinguish strong tremors followed by receding sea water, which drives them to evacuate to higher ground.

Meanwhile, the movement of undersea tectonic plates can set off huge waves that travel thousands of kilometres from the epicentre. That is why tsunami waves hitting the Maldives and the coast of India were not preceded by tremors like the quake that shook Aceh.

“When a tsunami comes without any quake ahead, it will surely be very difficult to predict,” says Nurmala of Ule Lhuee village, another survivor. “Tsunami victims like us won’t be able to gauge when the next tsunami is going to happen.”

Nurmala says she still relies on general signs that she saw in December 2004. She did not know that an earthquake with the potential to cause a tsunami could occur far beyond the Aceh region, with its resulting waves capable of reaching the area where she lives with few warning signs.

Nurmala was never taught how to identify these signs apart from what she witnessed in 2004, nor did she realise the importance of disaster awareness for her and people on Aceh’s western coast, particularly in areas still lacking early-warning instruments found in major cities.

“As far as I know, tsunami sirens can be found only in big cities like Banda Aceh and Meulaboh, not in areas further away,” says Nurmala. “We just rely on our simple knowledge and natural warning signs like those we have previously experienced.”

AFTER the 2004 tsunami, which claimed more than 35,000 lives in Sri Lanka and displaced 515,000 people on the island, several areas of research into early warning systems emerged.

The first multilingual trials of the Common Alerting Protocol (CAP) – a data format for exchanging public warnings and emergencies between alerting technologies – were carried out in Sri Lanka as part of the Hazard Information Project funded by Canada’s International Development Research Centre.

“It was an unexpected success,” says Rohan Samarajiva, who heads regional think-tank LirneAsia.

LirneAsia and its partners generate and apply knowledge to disaster risk reduction, primarily in the area of early warning.

In recognition of the important role played by Sri Lankans in the development of this technical standard, a meeting of CAP experts from 20 countries took place in the coastal town of Negombo in June this year, with the discussions centring on:

• advances in multiple links in the early warning chain;

• the sophisticated science behind improved detection and monitoring of earthquakes and tsunamis; and

• community readiness to receive public warnings and act appropriately.

Asked to explain the importance of CAP, Samarajiva, a former telecoms regulator, compares the current media and disaster management environments to those that existed in 1978 when a devastating cyclone hit Sri Lanka killing about 900 people.

“Then, there was only one electronic media organisation, the Sri Lanka Broadcasting Corporation. It had six channels, but the news and information on all its channels originated from one newsroom. It coordinated with the Sri Lanka Department of Meteorology, the sole entity responsible for cyclone warnings

“On the ground, there were far fewer electronic media devices than now, but this was compensated by some efficient officials who effectively moved people out of harm’s way,” says Samarajiva, who was working with the corporation then.

In comparison, he notes, there is now a multitude of media organisations and channels spanning TV, radio, mobile phones and the Internet. The likelihood of errors and distortions in warning messages as they pass through multiple links is that much greater now. The complexity of the first responder system is also higher.

CAP, he emphasises, was intended to reduce the likelihood of distortion and also increase the speed of communicating warnings.

In an ideal scenario, an authorised person would press a button, following which a formatted message would automatically and instantaneously be converted into different forms for transmission across multiple media.

The most significant contribution made by Sri Lankans to disaster management, however, is the development of the Sahana software suite

Created by volunteers in the aftermath of the tsunami, Sahana allows for systematic management of information on displaced persons, their locations, their needs for food and medicine, and so on.

It also facilitates the easy location and mobilisation of resources such as earth-moving equipment.

Sahana, incubated by the Lanka Software Foundation, has grown beyond Sri Lanka and is now one of the leading disaster management tools worldwide. It has been deployed in places like Haiti and is also part of the disaster preparedness toolkit in Manhattan.

A GEOLOGICAL time bomb is ticking in Indonesia, and the city of Padang on Sumatra’s western coast is sitting smack on top of it.

In the last decade, five major quakes, including the catastrophic 2004 Boxing Day tsunami, have struck the city of one million, giving it the dubious distinction of being the current earthquake capital of the world. Indeed, the level of seismic activity in western Sumatra is second to none.

While they may quibble about the details, experts at the Earth Observatory of Singapore believe that the next big one, which has been building up since 2000, will come in mere decades, a blink of the eye in a field where scientists more commonly study patterns in land and rock formations spanning millions of years.

This forecast is based on the work of the earth observatory’s director, geologist Kerry Sieh, and was first made nearly six years ago.

“Corals on the reefs of west Sumatra record in their annual growth layers the patterns of large earthquakes,” he says.

“These patterns repeat about every two centuries, which is about the time since the last set of great earthquakes and tsunamis there.”

A giant 8.8 magnitude earthquake and tsunami similar to but perhaps a bit smaller than the one that caused the waves of destruction 10 years ago will strike within a few decades, he believes.

The quake itself will damage or destroy many existing buildings and bridges, and the resulting tsunami will reach the shores of the Mentawai Islands within five to 10 minutes.

And in 20 to 30 minutes, it will hit the mainland of the west Sumatran coast, including Padang.

“Scientists can’t predict the exact day, month or year, but it will happen in the lifetime of the young people living there,” he says.

Massive earthquakes like this occur only in subduction zones where two of the tectonic plates that comprise the earth’s surface are converging, with one plate diving beneath another.

The Dec 26, 2004, earthquake happened because of the rupture of the Sunda Megathrust, which is the fault plane along which the Indian and Australian plates slide beneath the Sunda plate and Sumatra.

Singapore was spared because it is sheltered by surrounding land masses. In addition, the shallow waters in the Malacca Straits and South China Sea – unlike the deep waters in the Indian and Pacific oceans – act to dampen the fury of the waves and dissipate their energy.

Also, the Republic is at least 400km from the nearest fault line in Sumatra. While tremors can sometimes be felt here, widespread damage is unlikely.

Australia, lying south of the original fault line, was also spared major damage.

Prof Sieh and his colleagues from Nanyang Technological University and in Indonesia are now eyeing a 400km section further south, beneath the Mentawai Islands west of Sumatra. It is part of the fault line which makes up the 5,500km Sunda megathrust.

Called the Mentawai patch, it has remained intact for nearly 200 years, and is under tremendous and increasing stress.

“Large earthquakes on long, locked fault zones commonly trigger one another, and hence cluster together in time,” says Prof Sieh.

Adds Dr Sylvain Barbot, a principal investigator at the earth observatory who is working on the subject: “In the Mentawai area, we have seen great earthquakes occur to the north and to the south.

“We don’t know if the fault will generate two great or one giant earthquake, but the fault must move somehow to catch up with its neighbours.”

Another internationally respected expert on Sumatra earthquakes, Dr John McCloskey, professor of geophysics at Britain’s University of Ulster, likens the current build-up to the drawing of a bow.

“Off western Sumatra the bow is drawn tight,” he said back in 2010.

“The last shock happened more than 200 years ago and the stresses are probably larger now than they were then. The earthquake must happen soon.”

Prof Sieh adds that the intensity of the quakes in the last few years has been unprecedented, and no one can tell when the current cluster will end, although the countdown to failure has begun.

To forecast earthquakes and tsunamis reliably, Prof Sieh and fellow researchers at the earth observatory use a Global Positioning System to continuously collect, process, analyse and archive data on tectonic plate movements in the region.

They also examine sand deposits and corals to work out when the last big quakes occurred.

And in recent work in a cave in west Sumatra, strata of sand and other deposits swept in from tsunamis that occurred over the past 7,500 years have unveiled the longest and most detailed record yet of the natural disasters that have hit the Aceh coast.

Radiocarbon analysis of materials such as charcoal fragments, clamshells and remains of microscopic organisms, unearthed evidence of 10 tsunamis before the one in 2004, and the scientists now know that tsunamis may cluster in time.

His role, says Prof Sieh, is to provide sound science so that policy makers and people at risk can make the right decisions, and he and his team have been involved in public education and outreach efforts for years.

His advice to the residents of Padang and West Sumatra is this: “In most areas, there is not enough time to wait for official warnings or to see receding water or the tsunami itself.

“People living near the coast should evacuate to high ground immediately after feeling an earthquake that is strong or lasts longer than one minute.”

Additional reporting by Grace Chua

http://www.straitstimes.com/STI/STIMEDIA/2014/oceans-fury/chapter5.html

See other chapters:

http://www.straitstimes.com/STI/STIMEDIA/2014/oceans-fury/index.html Crushed

http://www.straitstimes.com/STI/STIMEDIA/2014/oceans-fury/chapter2.html   Survive

http://www.straitstimes.com/STI/STIMEDIA/2014/oceans-fury/chapter3.html  Respond

http://www.straitstimes.com/STI/STIMEDIA/2014/oceans-fury/chapter4.html  Rebuild