Palmer tsunami warning center registered Indonesia quake

JOHN DAVIDSON/Frontiersman reporter

PALMER -- When the world's most powerful earthquake in 40 years struck northwest of Sumatra, Indonesia at dawn Sunday, it registered at the West Coast and Alaska Tsunami Warning Center in Palmer, head scientist Paul Whitmore said.

The quake, which measured 9.0 in magnitude and, as of Monday morning, had claimed the lives of more than 23,000 people across South and Southeast Asia, triggered tsunamis that gathered to speeds of up to 500 miles an hour before crashing into coastal areas of Sri Lanka, India, Thailand, Indonesia, the Maldives and Malaysia.

Tsunami waves were believed to have reached heights of 40 feet or more, and decimated everything in their path.

Although official numbers are not available now, data will be collected by survey teams. Large tsunamis leave debris lines and water lines, Whitmore said, and teams of scientists will measure the heights of these lines and interview eyewitnesses to get a clear idea of how high the walls of water reached.

The warning center in Palmer is responsible for all of Alaska, the U.S. West Coast and Canada; it is the only tsunami warning center in charge of those areas, Whitmore said.

The next nearest warning center, located in Hawaii, covers the South Pacific and areas of South Asia that lack proper tsunami warning centers. Whitmore said there is a very primitive tsunami warning center in Indonesia, but it's mostly an "after-the-fact" operation because the communication infrastructure is so weak in those areas, it's hard to get the word out.

It took several hours for tsunami waves to gather and reach coastlines Sunday, officials said, but no effective warning system was in place to alert people to get away from coastal areas.

The tsunami warning center in Hawaii, which also registered the earthquake Sunday, put out a message saying there was no danger of tsunami waves from the Indian Ocean affecting areas in the South Pacific, Whitmore said.

Palmer's warning center can record earthquakes anywhere in the world that register more than 5.0 magnitude; anything over a 6.0 triggers an alarm, Whitmore said, and any quake over a 6.5 in the Pacific Basin prompts scientists in Palmer to issue a message and warnings, depending on where the earthquake occurred and how big it is.

Although large tsunamis can travel past coastlines and up rivers, Southcentral Alaska is most likely not in danger of being hit by a tsunami, Whitmore said. Since Cook Inlet is relatively shallow, a tsunami would lose much of its energy and speed as it traveled toward land.

Whitmore said the center is still measuring aftershocks of Sunday's quake, and expects them to continue for months.

According to a preliminary report from the U.S. Geological Survey's National Earthquake Information Center, Sunday's earthquake was the fourth-largest in the world since 1900 and the largest since the 1964 earthquake in Prince William Sound.

Whitmore said Southcentral has about one earthquake a day that registers a magnitude of more than 3.0 and about one a month with at least a 6.0 magnitude.

Contact John Davidson at john.davidson@frontiersman.com.