Tsunami warning system is tested
Peter Fimrite, San Francisco Chronicle Staff Writer
San Francisco Chronicle March 12, 2011 04:00 AM Copyright San Francisco Chronicle. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.Saturday, March 12, 2011
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.
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