JAKARTA, Indonesia — On Sept. 28, 2018, a 7.5 magnitude quake triggered a large tsunami that hit the Central Sulawesi city of Palu in Indonesia. It was the first of two massive tsunamis to hit the country this past year. Less than two months later, on Dec. 22, an unusual volcanic landslide triggered a tsunami in the Sunda Strait despite no recent earthquake in the region.
Together, they left thousands dead and homeless, and in both instances, there was no warning, leaving many to blame the high human toll partly on malfunctioning tsunami warning systems that had been set up after the 2004 Boxing Day tsunami, which killed over 200,000 across the Indian Ocean.
“The goal is to fix the systems and get what we need out of them.”— Andrew Schroeder, director of research and analysis, Direct Relief
While some observers noted the lack of functioning buoys in the region, others argued that the lack of reliable funding played a key role. The reality is likely that design shortfalls, the uniqueness of both tsunamis, and existing challenges with last-kilometer ground alerts all played a role in the system’s failure and inability to warn residents.
“The Palu was almost certainly the compound result of the earthquake and several associated and coincident landslides below the ocean surface,” said Adam D. Switzer, principal investigator at the Earth Observatory of Singapore. “There is no current technology that can give an adequate tsunami warning for a compound event like this.”
Tsunamis present particular challenges due to the rare and often unique nature of both earthquakes and coastal basins. Not every earthquake, even large ones, result in a tsunami, and accentuating factors such as geography and seafloor make-up impact its size and scope. Nevertheless, in the months since last year's disasters, there has been a renewed push to improve Indonesia’s warning system through the use of new technology, and there is a key role for the development community to play in this.
Limitations of the existing system
Initially, failure of the warning systems led many to blame government ministries, such as the Indonesian National Board for Disaster Management, for mismanaging funds and not properly maintaining the system.
“It was an unfortunate situation, and I hope there’s not a backlash against the idea of tsunami alerting systems,” said Andrew Schroeder, director of research and analysis at Direct Relief, an NGO that conducted relief activities in Sulawesi. “The goal is to fix the systems and get what we need out of them.”
The limitations of the existing system were known well before the Palu disaster including its reliance on the malfunctioning deep water buoys, remote earthquake sensors, and satellite technology, and high upkeep costs.
In 2013, the U.S. National Science Foundation’s Interdisciplinary Research in Hazards and Disasters Program gave a grant to a team of researchers led by Louise Comfort, a researcher at the University of Pittsburgh’s Center for Disaster Management, which included Indonesian researchers and government agencies. The goal — create a cheaper, more sustainable system that could be deployed across the Indonesian archipelago, and elsewhere.
“The critical issue in early tsunami detection is you have to have to measurements of the change in the water column,” Comfort said. “That was what was missing Palu, and in [Sunda] too.”
Comfort’s team has designed and tested a system that uses acoustic signals transmitted from the seabed to detect changes in the water column in tropical waters. It would have, Comfort argues, detected both the Palu and Sunda tsunamis.
“The major advantage is cost, and it’s using the natural environment of Indonesia in an intelligent scientific way to provide information for early detection of tsunamis,” Comfort said.
Starting in late August, this acoustic system has begun to be installed by Indonesian authorities along the Mentawai Basin, on the southern coast of Sumatra Island, near the city of Padang. This area saw an earthquake and tsunami event in 2009, which resulted in more than 1,000 deaths, and is considered a high-risk area for natural disasters. After ensuring it is well functioning, Comfort’s team hopes to expand it to other parts of the archipelago. For that, they’ll need more international involvement.
Role of the international community
“Somebody has to pay for it,” said Schroeder of Direct Relief. That burden cannot be placed on a low-income country like Indonesia alone. “The international community has a stake in making sure countries like Indonesia are prepared against high impact catastrophes.”
In fact, international aid was instrumental in setting up the initial Indian Ocean tsunami warning system and Indonesia’s own system. Then, the German government, through the GFZ German Research Centre for Geosciences, played a key role. But that collaboration ended in 2011, and cuts to the budgets for Indonesian government agencies responsible for system upkeep are part of the reason that it did not function properly last year and why alternative technologies have yet to be deployed.
One entity that hopes to galvanize a new effort to expand the acoustic system and prevent a repeat of last year’s lack of warnings is the Swiss RE Foundation, based in Switzerland.
“The international community has a stake in making sure countries like Indonesia are prepared against high impact catastrophes.”— Andrew Schroeder, director of research and analysis, Direct Relief
“As a reaction to [last year’s] tsunamis we decided to look in funding efforts to improve the partly dysfunctional tsunami warning system in Indonesia,” said Stefan Huber Fux, director of the foundation. They decided to back Comfort’s team’s system due to tested effectivity and cost. “This method of tsunami detection, using acoustic communication, offers advances in accuracy and timeliness of tsunami detection at a major reduction in cost” Huber Fux said.
Once the system is installed near Padang, the next step will be bringing more funding on board.
“We have started to activate the interest of other philanthropic and donor organizations that could consider supporting the scaling. If there is evidence that something is working, we strive to replicate also with the support of others,” Huber Fux said.
Of course, a warning system is only part of the picture. The Palu experience also shows that there may also be a need to design more locally relevant tsunami disaster education campaigns. What works in a place like Aceh, or Padang, with recent memories of tsunamis, is different than Palu, which had not seen a tsunami in generations. Different types of educational campaigns need to be implemented in regions that had not seen recent tsunami events.
“Rather than having a one-size fits all way of communicating — we should be clear about specific context in which that information needs to be communicated,” Schroeder said. “A uniform [curriculum] may not be the best way to do it if you really want people to listen carefully to nuanced messaging around alerts.”
If all goes as planned, Indonesia may soon have a more robust tsunami warning system, and better local preparedness as well. There’s global implications, as Comfort and Swiss RE believe, if successful, this system can be used in other similar coastal basins in tropical countries facing tsunami risk around the world, including India, Bangladesh, and West Africa.