The Killer Quake
Story
India not part of global warning system
Agencies
Denver, December 27, 2004
The catastrophic death toll in Asia caused by a massive tsunami might have been reduced had India and Sri Lanka been part of an international warning system designed to warn coastal communities about potentially deadly waves, scientists say.
India and Sri Lanka are not among the 26 countries that make up the International Coordination Group for the Tsunami Warning System.
The system predicts where tsunamis will strike up to 14 hours in advance.
It relies on a network of earthquake seismic sensors and tidal gauges attached to buoys in the oceans. However, the network's western edge stops near Thailand and Singapore and does not extend into the Indian Ocean.
Some 5,300 people in India and Sri Lanka were among the more than 11,000 people killed after being hit by walls of water triggered by a tremendous earthquake on Sunday morning off Sumatra.
The warning system is designed to alert nations that potentially destructive waves may hit their coastlines within three to 14 hours.
Scientists said seismic networks recorded Sunday's massive earthquake, but without wave sensors in the region, there was no way to determine the direction a tsunami would travel.
A single wave station south of the earthquake's epicentre registered tsunami activity less than 60 cm high heading south towards Australia, researchers said.
The international warning system was started in 1965, the year after tsunamis associated with a magnitude 9.2 temblor struck Alaska in 1964.
It is administered by the National Oceanic and Atmospheric Administration.
Member states include all the major Pacific nations in North America, Asia and South America, was well as the Pacific islands, Australia and New Zealand, France and Russia.
However, India and Sri Lanka are not members. "That's because tsunamis are much less frequent in the Indian Ocean," Charles McCreary, director of the Pacific Tsunami Warning Center near Honolulu, said.
"They had no tidal gauges and they had no warning," said Waverly Person, a geophysicist at the National Earthquake Information Center in Golden, Colorado, which monitors seismic activity worldwide.
"There are no buoys in the Indian Ocean and that's where this tsunami occurred."
Researchers say the earthquake broke on a fault line deep off the Sumatra coast, running north and south for about 966 km or as far north as the Andaman and Nicobar islands between India and Mynamar.
Warning system does not extend to Indian Ocean nations
"It's a huge rupture," McCreary said. "It's conceivable that the sea floor deformed all the way along that rupture, and that's what initiates tsunamis".
Tsunamis as large and destructive as Sunday's typically happen only a few times in a century.
"It was a big tsunami, but it is hard to say exactly how many waves there were or what happened," McCreary said.
The warning system analyses earthquake information from several seismic networks, including the US Geological Service.
The seismic information is fed into computer models that "picture" how and where a tsunami might form. It dispatches warnings about imminent tsunami hazards, including predictions how fast the waves are travelling and their expected arrival times in specific geographic areas.
As the waves rush past tidal stations in the ocean, bulletins updating the tsunami warning are issued. Other models generate "inundation maps" of what areas could be damaged, and what communities might be spared.
© HT Media Ltd. 2004.