Tsunami warning system gets boost
By Jan TenBruggencate
Advertiser Science Writer
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The earthquake and tsunami that devastated the coastlines of nations on the Indian Ocean a year ago shook up local civil defense officials and tsunami warning system scientists — and loosened purse strings for tsunami warning gear.
In Hawai'i, the devastation on Dec. 26, 2004, has led to new equipment and improved procedures that have reduced warning times in case of a locally generated tsunami.
Improvements include a new tsunami-sensing buoy off the Big Island to pick up signs of a locally generated tsunami. And a new warning protocol allows authorities to call 911 and have police immediately turn on sirens — because if a tsunami is generated on the Big Island, Honolulu may have only 27 minutes to evacuate.
"What happened with the Sumatra event, it made people realize what devastation a tsunami can cause," said Jeanne Johnston, tsunami program manager at the state Civil Defense Division.
Officials also said a network of 39 new tsunami-sensing buoys is to be installed over the next couple of years around the Pacific, to help warn Hawai'i and other areas.
Last year's tsunami also has led to improvements at the national level.
In Seattle, federal researchers have developed new computer simulations that can better predict if a deep-sea quake will produce a tsunami, how big it will be and how it will impact coastal communities, including Hilo.
"The idea is to pre-compute a lot of the information so we can do it in minutes instead of hours," Diego Arcas, a forecaster for the Pacific Marine Environmental Laboratory at the National Oceanic and Atmospheric Administration's Seattle station told the Seattle Post-Intelligencer.
Last week the White House announced plans to develop a national preparedness plan that would increase earthquake and volcano monitoring systems, deep-ocean buoys and other high-tech means of alerting oceanside communities of tsunamis.
Last year's Indian Ocean tsunami killed or left missing more than 220,000 people in 11 countries and "demonstrated international vulnerability," said John Marburger, Bush's top science adviser.
The tsunami rose a massive 30 feet. Sumatra was the hardest hit, losing some 128,000 people. The wave was recorded as far away as Peru and northeastern Canada.
Specifically, the new plan will:
Among the improvements in Hawai'i is the expansion of DART (Deep ocean Assessment and Reporting of Tsunamis). The system involves a pressure sensor moored to the ocean floor, with a buoy that is capable of immediately transmitting the sensor's readings to satellites.
As a tsunami passes through deep water, it is virtually invisible on the surface, but its force can be monitored by sea floor pressure sensors.
A half-dozen older-generation DART buoy systems have been in place off Alaska and California and between Hawai'i and South America. Emergency officials have wanted to add more such systems not only to better gauge incoming waves from those directions but also to cover events coming from the South Pacific and from Japan. They also have sought a means of detecting locally generated waves. The federal government has authorized an array of 39 such buoys — expanding a system that has just 11 today — to be installed within the next year, said Ed Teixeira, vice director of the state's Civil Defense Division.
The first has been installed. It is a new generation DART II buoy moored to the ocean floor about 30 miles off the Kona Coast, where it will provide an accurate gauge of the strength of any Big Island earth movement that could threaten the rest of the state with a tsunami.
The device is the newest version of NOAA's DART system. The sea floor sensor constantly senses the pressure of the water above it, and reports it to the buoy, which in turn sends the information through the Iridium global satellite network. The DART II system provides a quicker reporting time than older buoys that used geostationary GOES satellites, Teixeira said.
The state's warning system also has gotten attention.
Hawai'i, partly because of its experience with previous fatal tsunamis, has one of the most advanced warning systems in the world. During an emergency, sirens go off in almost every community, notices appear on television stations and radio stations have emergency programming capabilities.
One of the key fears for Hawai'i is a locally generated tsunami since it would give Island residents only minutes to respond.
A report of a Big Island event would reach the Pacific Tsunami Warning Center within a couple of minutes, but Hawai'i Civil Defense offices are not staffed on a 24-hour basis, and officials could not get to the office in time to issue a statewide alert.
"We've improved the system for warning the public," Teixeira said. The warning center will directly call county emergency officials — generally the county warning points are the emergency dispatchers you get when you dial 911 — who will be told to sound the state's sirens. At the same time, text "crawlers" appear on television sets, directing them to the channel that has emergency information.
If the system works right, residents would get the word within 10 minutes or so. If people living near the coastlines on O'ahu begin heading inland, or if they're in tsunami-resistant buildings, heading upstairs, it should be enough.
"It's the best we can do," Teixeira said.
But he said residents need to be alert to no-tech solutions as well. A powerful 1975 Big Island quake that caused a local tsunami was felt across the island chain — all the way to Kaua'i.
"People need to respond to the ground shaking. If you feel it, that's your automatic signal to seek safe ground," he said.
The Associated Press contributed to this report.Reach Jan TenBruggencate at jant@honoluluadvertiser.com.
