A TSUNAMI simulation exercise involving 24 nations, including Singapore, began in Jakarta on Tuesday morning.
Called Indian Ocean Wave 14, the two-day exercise is intended to test the ability of the communications systems of Regional Tsunami Service Providers, namely Australia, India and Indonesia, and their speed in disseminating alerts to 24 participating countries and agencies in the Indian Ocean.
This exercise, led by Unesco, is the third after two others in 2009 and 2011.
In Jakarta, where shortly after 7am local time, a loud beep warned that an "earthquake" had been detected in the south of Java. Officials at the nerve centre of Indonesia's Meteorology, Climatology and Geophysics Agency (BMKG) in Jakarta then swung into action, checking the intensity of the seismic activity, studying data spewing out from a line of computers and running programs to calculate the impact.
Within five minutes, the first global bulletin was sent out via text message, e-mail and fax to the nations, alerting them to the quake intensity, location and assessment of tsunami occurrence.
Yesterday's "quake" was of magnitude 9.1, the same intensity as the devastating quake that struck the west coast of Sumatra on Dec 26, 2004.
The resulting tsunami killed some 300,000 people in 14 countries, over half of whom were Indonesians. India had the third highest death toll of 18,000.
In the past decade, an extensive system, including a network of deep sea sensors and coastal tidal gauges, has been put in place to detect and predict tsunamis triggered by undersea tremors.
Unesco's Indonesia coordinator for the Indian Ocean Tsunami Information Centre, Mr Ardito Kodijat, said tests were needed to maintain standards and build confidence in the ability of regional officials.
Experts also say the system known as Deep-ocean Assessment and Reporting of Tsunamis has worked well.