With Tsunami Images Still Fresh And Terrifying, Research Ramps Up In U.S. Labs
BY Paul Glader
Oregon State University scientist Solomon Yim, director of the O.H. Hinsdale Wave Research Laboratory, says that each time a major tsunami hits, his $20 million lab sees an uptick in research projects from his average of $2 million in annual grants. "Before 2004, tsunamis were not on the radar screen of Americans," says Yim. That all changed with the Indonesian tsunami, and in 2005, the departments of transportation for the three western coastal states commissioned more research.
The Japanese tsunami may be the most influential of all when it comes to spurring research and increasing public awareness. Historically, tsunamis often occurred at night or in places where people didn't have video cameras. But the dramatic images from Japan may have--literally--shed new light on big-wave disasters.
"There is no question the video footage of the Japan tsunami is incredible," says Lori Dengler, chairwoman of the geology and oceanography departments at Humboldt State University in Arcata, Calif., who heads the Humboldt Earthquake Education Center. "Prior to that, we had relatively no good footage of the tsunami."
Yim's lab has expanded to six people, up from three, in the past five years. He is studying, for example, the debris kicked up by a tsunami, and the impact on structures. "The coastal engineers and harbor people need to take tsunamis into account for design," he says. "They do have bridges sticking right out into the ocean." (Note to engineers: Don't do this anymore.)
A structural engineer with a background in computational fluid dynamics, Yim researches how fluids impact structures. His tsunami center, which opened in 2000, now has two large basins, one of them 342 feet long. Imagine a much bigger, scarier water-park pool that simulates giant, destructive waves. Now, he is busy calculating the physics of damage a tsunami could cause on bridges, roads, and other infrastructure on the West Coast.
His findings suggest cylinders resist tsunamis better than other shapes of pillars that hold up bridges. Any corners or abrupt changes stick out and catch water, while the cylinder "is the optimum shape." On buildings that must use I-beams and other corners, he said engineers should focus on creating a strong frame with tearaway panels to withstand damage.
As for Dengler, who is heavily involved with the efforts the National Oceanic and Atmospheric Administration, which oversees the National Tsunami Hazard Mitigation Program, she's helping to develop and test an instrument that tracks the speed of tsunami currents. Their prototype in Humboldt Bay measures current velocity, and caught early signals of the March 11 Japanese earthquake and tsunami. They want to add more such instruments in California to improve earthquake and tsunami detection.
"It's the speed at which the water flows that may cause the damage, particularly if it carries debris," she said. In the past, tide gauges recorded the height of tsunami waves, but not the current speed. "We are really at the very beginning to describe those current philosophies."
It's not just public entities that are getting in on the research and educational initiatives. The U.S.-based giant FM Global insured nearly 3,000 properties in Japan that sustained less than $150 million in damage. "Whenever there's a significant issue like in Japan, there are always questions of where else it could happen," said Lou Gritzo, a vice president and manager of research at FM Global. "The Pacific Northwest is on the short list."
Gritzo said the insurer is working with clients to prevent damage with methods such as turning off natural gas to buildings to avoid fire damage during an earthquake, and keeping sprinkler lines in working order. It also does computer modeling of tsunamis.
All this is not to say that the U.S.--which racked up $60 million in damages on March 11 as waves from Japan's tsunami reached the West Coast--is where it needs to be with tsunami research or preparedness. Despite the near-meltdown at the Fukushima nuclear plant in the wake of the tsunami, and the flurry of new research going on in the U.S., Japan still is "by far, the most prepared country in the world for tsunamis," said Yim.
Meanwhile, the risks of a West Coast tsunami are far from hypothetical.
The Cascadia Subduction Zone, which spans 600 miles from British Columbia to Northern California, has potential for generating a large tsunami that could ravage parts of Washington, Oregon, and northern California.
"The Cascadia Earthquake is our biggest concern," says Dengler. "We are talking about exactly what happened in Japan." She predicts Seattle, Portland, Sacramento, and San Francisco would have earthquake damage, followed by huge waves arriving 10 to 15 minutes later. "We're talking about a very, very big tsunami that happens very, very quickly."
Yim and other scientists say the historical record shows a massive tsunami struck the coast just over 300 years ago, on Jan. 26, 1700, after a 9.0 earthquake rattled the ocean floor less than 100 miles off the coast of Oregon. Paleontologists have found tsunami deposits up the Columbia River. Tree-ring indicators and written records in Japan indicate the tremor also sent water across the ocean.
With a major tsunami like that typically recurring every 250 years, the Cascadius is 50 years overdue. Yim puts chances of another major West Coast tsunami in the next 50 years as high as 85%.
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