In Thailand, buoys to avoid a tsunami as catastrophic as in 2004

Almost 1000 kilometers from the Thai coast devastated by the 2004 tsunami, engineers plunge a detection buoy into the sea, an essential link in a prevention system intended to prevent such a deadly disaster from happening again.

On December 26, 2004, a magnitude 9.1 earthquake at the bottom of the Indian Ocean triggered a gigantic tsunami that killed around 230,000 people in around ten countries in South and Southeast Asia.

At the time, prevention systems were rudimentary and it was impossible to warn the millions of people living on the coasts of the Indian Ocean.

In the years that followed, several governments consulted to develop a global tsunami information system, drawing on a network of six detection buoys set up in the Pacific by the National Oceanic and Atmospheric Administration of the United States.

Known as Deep-Ocean Assessment and Reporting of Tsunami (DART), the system now has 74 buoys around the world.

Each of them floats on the surface while being attached to the seabed. The buoys monitor signals from a seismic sensor placed far below, as well as changes in water level.

Installed in some of the harshest working environments on earth, these battery-powered buoys need to be replaced every two years. Currently, only 50 of them are functional, but the network was designed to ensure coverage in all situations.

Faster alerts

Earlier this month, the crew of the research vessel MV Seafdec gently dipped a replacement buoy, a yellow cylinder about two meters in diameter, into the Indian Ocean, 965 kilometers from the Thai coast.

The same team also sought to replace a buoy in the Andaman Sea, 340 kilometers from the coast, but failed and will carry out a new mission in the coming weeks.

The alert system has great utility, it can save lives on the coastssays Shawn Stoeckley, a mechanical engineer at the Science Applications International Corporation (SAIC), one of the largest American technology companies.

In Thailand, the tsunami killed more than 5,000 people according to official data, and 3,000 were missing.

Now the country has two DART buoys linked by satellite to 130 alert towers in 6 coastal provinces, all equipped with sirens and loudspeakers that broadcast messages in 5 languages.

Before 2004, 15 to 50 minutes could pass before a warning was issued, says Laura Kong, director of the International Tsunami Information Center at theUNESCO.

Today, we can typically receive an alert within five to seven minutes.

One day, the system will prove itself, insist the experts of theHIM.

There is 100% chance that another tsunami of the same magnitude as in 2004 will occur one day or another, warned Bernado Aliaga, head of the tsunami resilience section of UNESCO, during a conference marking 20 years of the tragedy . It could happen tomorrow, in 50 years or in 100 yearshe added.

Tricks still essential in the cell phone era

Unlike 20 years ago, cell phones are now ubiquitous and alert apps are available, but alert towers are still vital, residents say.

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The head of Khuak Khak village in southern Thailand, Songsil Nodharith, 51, helped residents evacuate without even taking their things during a false alarm triggered in the middle of the night last year. He calls on the authorities to ensure that the system is properly maintained.

In Sri Lanka, where 31,000 people died in 2004, three-quarters of the 77 tsunami warning towers are no longer functional because communications equipment has become obsolete, theAFP the head of the island's disaster management center, Udaya Herath.

Instead, telecommunications companies identified 70,000 key contacts in coastal areas, such as hotel managers, to receive alerts and evacuation orders in the event of imminent danger.

In Thailand, false alarms have sometimes caused panic, but that doesn't stop residents from having faith in the system.

The fishing village of Ban Nam Khem in southern Thailand was hardest hit in 2004. Trawlers rammed homes and 800 residents were killed.

Manasak Yuankaew, 48 years old and now the village chief, lost four members of his family that day.

We have our say herehe said to theAFP. Running away 100 times for nothing is better than not running away at the crucial moment.