October 1, 2009

Ideal Conditions Made Samoa Tsunami More Devastating

Experts say American Samoa was the victim of a perfect storm during the recent tsunami that has resulted in a death toll of 150 people and rising.

The region was subject to a massive magnitude 8.0 earthquake that triggered strong winds and enormous ocean waves. Because it occurred in the ocean floor beneath deep water, the waves were larger and it quickly gained more speed and power.

"Put that all together and there was less than 25 minutes, maybe as little as 13 minutes, between the ground shaking and the first tremendous waves swamping Samoa," said the Associated Press.

"This is the kind of earthquake one would expect to be very destructive in the areas close to the epicenter, and unfortunately it was," said Stuart Weinstein, deputy director at the Pacific Tsunami Warning Center in Ewa Beach, Hawaii.

Response teams had less than 25 minutes from when the quake hit to issue a public warning of the coming tsunami. What's more, the computerized system put in place to alert relief agencies was knocked offline, making an immediate response all the more difficult.

"People assume that if they have an early-warning system, their problems are solved," James Goff, director of the Australian Tsunami Research Centre, based at the University of New South Wales in Sydney, told the Christian Science Monitor.

"But it's only one of a suite of ways of being aware what's going on. What's really needed is education about the natural indicators. If you live by the coast and there's a very large earthquake, or if you see the water receding very quickly and going much lower than low tide, you need to move uphill."

The outer rise earthquake cause the sea floor to split open in a pattern that created four waves of 15 to 20 feet in height.

"It's one of those heart-wrenching situations where you have some time, but what can you do? It's not much time," Eric Geist, at the U.S. Geological Survey in Menlo Park, Calif., told the AP.

Geist said the recent event was the fourth most powerful outer rise earthquake on record.

He added that the water was so deep "“ as much as 3 miles "“ that the tsunami could have sped through the region at 530 mph.


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