Indian Ocean Tsunami:

Scientists new findings say Tsunami waves 80ft high hit Indonesia

Surfersvillage Global Surf News, 08 February 2005: - - Scientists studying the Indian Ocean tsunami have discovered startling evidence that the killer wave/s, at least for one coastal area in northern Indonesia, were much larger than earlier believed. The new findings, of keen interest worldwide to researchers seeking insights into the mechanics of this disaster, also translate into a disturbing suggestion that the experts have significantly underestimated the magnitude of the tsunami threat in the Pacific Northwest and perhaps to coastal communities around the Pacific Ocean.

"It's just staggering," said Andrew Moore, a scientist at Kent State University who was on a research team, led by Yoshinobu Tsuji of the University of Tokyo, that recently returned from studying the wave's trail of destruction on the west coast of Sumatra. Moore, Tsuji and their colleagues found preliminary evidence the tsunami's height along an extensive section of shoreline south of the city of Banda Aceh averaged about 80 feet above sea level, with "run-ups" on inland slopes often reaching well over 100 feet. They estimated the wave's average velocity on shore at 45 feet per second.

"It's mind-boggling to think about," said Vasily Titov, a mathematician and tsunami computer modeler at the Pacific Marine Environmental Laboratory in Seattle. The lab, operated by the National Oceanic and Atmospheric Administration, is host to some of the world's top tsunami scientists. "Our worst-case scenario may not be the worst-case scenario," acknowledged Titov.

Most estimates of the Dec. 26 waves' maximum height above sea level (sometimes referred to as "flow depth" to distinguish it from onshore "run-up" heights) had put it at 30-35 feet -- primarily in parts of Indonesia nearest the undersea earthquake.

Scientists studying the Indian Ocean tsunami, which killed at least 260,000 people, had heard the reports of higher waves -- of branches and bark stripped off the first 80 feet of trees, of water marks and roof damage found at or beyond the height of six- or seven-story buildings -- but most figured these were the results of the wave running up slopes or isolated instances of "focusing."

A tsunami wave can get "focused" or boosted suddenly in one location as it comes on land by undersea canyons or other near-shore geographical features or structures that squeeze the massive surge of water into a narrower outlet -- much like a nozzle increases the force of the water coming out of a hose.

But Moore said his team's wave-height measurements were consistent over a long stretch of coastline and found well back from any slopes, indicating these were direct measurements of the overall elevation of this massive wall of water as it came on shore. "It's just so far beyond what any of us have ever dealt with before," said Moore, who before moving East pursued tsunami research at the University of Washington.

A British research ship, the HMS Scott, is conducting surveys of the seafloor off Sumatra and has found evidence of massive submarine landslides. Scientists say it's also possible these undersea landslides magnified the waves.

Complete article available at Seattlepi.com
Contributed by K38 Rescue

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Shawn Alladio
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