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INDONESIA: Tsunami early warning system a work in progress

Jakarta, 31 December 2009 - Five years after the Indian Ocean tsunami, Indonesia's early warning system remains a work in progress, officials and experts say.
Indonesia began setting up an early warning system in 2005, a year after a 9.2 Richter scale earthquake off Sumatra triggered a tsunami which left over 230,000 dead, 1.8 million displaced and 470,000 homes and buildings destroyed in 13 countries.

The Indonesian Tsunami Early Warning System has three levels: an earthquake monitoring system, a sea level monitoring system, and a computer modelling system able to generate different tsunami projections.

It collects data from seismometers, tide gauges, and GPS tracking units mounted on buoys to detect subtle changes in water pressure which could indicate an incoming tsunami, as well as ocean bottom satellite-linked sensors, allowing it theoretically to issue a tsunami warning at a regional level five minutes after an earthquake.

The warning would be relayed to the authorities, the media and communities likely to be affected.

"Right now we have in place what we call Service Level 1 [the earthquake monitoring system]. We use earthquake monitoring equipment to determine earthquake parameters and the potential for tsunami generation," Fauzi (like many Indonesians he goes by only one name), head of the Tsunami and Earthquake Centre in Jakarta, told IRIN.

Service Level 2 - the sea level monitoring system - is expected to be completed in April 2010, while Service Level 3 - tsunami modelling - should be in place by 2011, Fauzi said.

Under the system, a tsunami warning will be issued for any undersea earthquake with a Richter scale magnitude of 7.0 or higher and a depth of less than 70km.

When earthquake data indicate a potential tsunami, computer predictions of the tsunami's height, volume and impact will be generated, as well as its estimated arrival time at different points along the coast.

Fauzi said the sea level monitoring system was expected to be completed in 2010, along with the ability to produce predictive information about any tsunamis which might affect Java and Sumatra.

He said 50 tide gauges had been installed along the coasts of Java, Sumatra, Sulawesi and the Papua region and 20 more tsunami buoys would be installed across the country in 2010.

"We have been facing a lot of problems operating the buoys. They often break down" said Fauzi.

However, Fauzi said he was optimistic the entire system, supported by countries such as Germany, China, France and the USA as well as UN agencies, would be ready by 2011.

Culture of preparedness

Ardito Kodijat, programme officer for the UN Educational, Scientific and Cultural Organization (UNESCO)-sponsored Jakarta Tsunami Information Centre (JTIC), said regional capacity and instilling a culture of preparedness could prove greater challenges than putting in place the warning system.

"The regions [provincial level and lower] remain a weak link in the overall early warning system," he told IRIN, adding: "There's so much to do in terms of education and safety facilities. It's not an easy task and takes a long time."

Kodijat said UNESCO was working with the Indonesian Institute of Sciences to educate people in disaster-prone regions about disaster preparedness.

Fauzi agreed with Kodijat that educating the public was the harder part: "Developing a culture of preparedness is a long process. It involves education from the elementary level on up."

Dissemination of warnings

Danny Hilman Natawidjaja, a geology researcher at the Indonesian Institute of Sciences, said relaying a tsunami warning to communities could also be a problem.

"So far the dissemination of tsunami warnings has used telephone and SMS, and I don't know whether sirens are working," Natawidjaja said.

Sirens have been installed in coastal areas on Java, Sumatra and Bali and are tested every month, Fauzi said, adding that more sirens would be installed in Gorontalo, North Sulawesi and the Maluku islands next year.

Natawidjaja and several other scientists who have studied Sumatra's geological fault line predict major earthquake in the West Sumatra area in the next three decades, generating a tsunami equal to that which devastated hit Aceh Province five years ago.

"I don't think any region is ready for a tsunami. If a tsunami happened now, the number of casualties would still be high," he said.

Source: www.irinnews.com