Tsunami warning system is tested

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If he were alive, Thomas Jaggar would be proud of the U.S. tsunami warning system after Friday's devastating earthquake in Japan sent a surge of ocean water hurtling toward the West Coast.

The founder of the Hawaiian Volcano Observatory couldn't even get the harbormaster in the coastal town of Hilo to listen in 1923 when he warned about a "tidal wave," which promptly rolled into town, killing at least one fisherman.

It took only 12 minutes after the 8.9 magnitude quake hit Sendai on Friday for the National Oceanic and Atmospheric Administration to alert emergency workers in California, Oregon, Washington and Alaska that a potentially catastrophic tsunami was heading their way.

By daybreak, there were evacuations, broadcast alerts and even freeway signs warning people to stay away from shore along the northern coast, including potential hot spots in Crescent City, San Francisco, Half Moon Bay and Santa Cruz.

"The improvements in the warning system are absolutely huge from where we were even a decade ago," said Lori Deng-ler, the chairwoman of the oceanography and geology departments at Humboldt State University, who has worked extensively with state and federal officials developing the U.S. warning system, which is part of the Tsunami Warning System in the Pacific, a partnership of 26 nations in the Pacific Rim.

"This event will help us improve what we do now, what works and what doesn't," she said. "We already know some people flocked to the beach and other people drove 50 miles away from the coast. We may have lost someone, so that is certainly a grave concern, but we are moving in the right direction."

The key to the system was the installation over the past seven years of dozens of sensor buoys throughout the Pacific. There were only six buoys, in the Deep-ocean Assessment and Reporting of Tsunamis, or DART, when tsunamis spread throughout the Indian Ocean in December 2004, killing more than 200,000 people. In most cases, there was no warning at all, a fact that was tragically clear in videotapes showing bathers flocking to the shoreline or standing around gawking as the killer waves rolled ashore.

Buoys sounded alert Friday

Laura Furgione, the deputy assistant administrator for the NOAA National Weather Service, said there are now 39 DART stations, the vast majority in the Pacific Ocean. She said the pressure sensors mounted to the ocean floor had alerted scientists early Friday morning that a tsunami was heading toward California.

The biggest waves Friday were 4.6 feet in Hilo, Hawaii, and 8.1 feet in Crescent City (Del Norte County), Furgione said. The Crescent City surge devastated a harbor, sunk and battered boats and swept a man out to sea.

It is significant that scientists can track a tsunami across the Pacific, considering how little was known about the phenomenon 88 years ago when Jaggar made that first futile warning. In fact, every development in tsunami detection was prompted by a disaster.

System goes back to 1949

The United States started a rudimentary tsunami warning program at Ewa Beach in Honolulu in 1949, three years after a tidal wave caused by an earthquake in the Aleutian Islands devastated Hilo. The international Pacific Tsunami Warning System was created by NOAA after the 1960 Chilean earthquake and tsunami killed dozens in Hawaii and as many as 200 people in Japan.

NOAA expanded the warning system in 1967 by adding the West Coast and Alaska Tsunami Warning Center in Palmer, Alaska. The expansion was in response to the horrific 1964 Alaskan earthquake and tsunami, which killed 132 people, including some in California. In 1982 the center added California, Oregon, Washington and British Columbia to the warning system.

The 2004 Indian Ocean tsunami prompted the warning center to increase staff from eight to 18 people, place more than 33 ocean monitoring stations at a cost of about $600,000 per buoy, and extend coverage to the Indian Ocean, South China Sea, Caribbean, Puerto Rico and U.S. Virgin Islands, officials said. What was a $2.3 million annual program in 2004 now costs $28 million a year in federal funding, Furgione said. She said there are 83 tsunami-ready communities, with warning systems in place, along the West Coast.

But the most important improvement, according to experts, is how the public now perceives tsunamis. The myth is of a single, giant wave.

Eric Geist, a geophysicist for U.S. Geological Survey, said the term tidal wave is a misnomer because tsunamis are not related to tides. They are caused by large earth movements that displace water, sending it surging across the ocean. What's unique is that the water moves in wavelengths that can be hundreds of miles long but are barely noticeable at sea. When the rushing waves reach shallow water, the huge volume of water gets compressed.

"You are transmitting a lot of energy into the water," he said, like trying to squeeze a gallon of water into a smaller container. Surges can continue, especially around harbors and other inlets for up to 12 hours.