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Ewa Beach Center Tracks Tsunamis

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Ewa Beach’s Pacific Tsunami Warning Center is a mecca of activity with new developments in scientific technology occurring on a regular basis.

“This past year has been pretty busy,“said director Dr. Charles McCreery. “We’ve had more events than usual.”

With tropical storm Flossie, tracking Peru’s deadly earthquake, the development of new technology to better measure a tsunami’s impact and seismic network upgrades, there’s never a dull moment for McCreery and his team of scientists and geophysicists.

Since a major earthquake in the Indian Ocean in 2004, there’s been more government support for improving tsunami warning systems (since earthquakes can cause tsunamis) at various locations, including here in Hawaii. The improvements are being driven by the scientific research community, McCreery said, with a focus on better predicting tsunami impacts. Hence the need to develop new technology to more accurately measure a tidal wave.

About 10 years ago, the Pacific Marine Environmental Laboratory in Seattle, Wash., developed a device - called the D.A.R.T (Deep Ocean Assessment and Reporting of Tsunami) buoy - to measure a tsunami in the middle of the ocean. D.A.R.T is the predecessor to tide gauges that, for example, can be placed in a harbor and used to gather data, but are not as accurate at the D.A.R.T.

“It’s a pressure sensor that sits on the ocean floor, measuring how much water (goes) over it,” explained McCreery. “It’s sensitive enough that it can measure less than 1 centimeter change in height (of the water). Tsunami waves can be 100 miles long.

“The trick is to get (the information) back to the warning center. An instrument on the bottom sends signals to a buoy on the surface. It does it acoustically (through) sound waves - the buoy sends a signal through a satellite link.”

McCreery noted that there are 27 D.A.R.T.s in the Pacific Ocean.

McCreery also explained that upgrading the local seismic network is important because warnings for a locally formed tsunami would need to be sent out quickly. Fortunately for Oahu, Ewa’s tsunami center can use instruments that monitor the volcano on the Big Island to monitor seismic activity and gather data on potential earthquakes.

Aside from explaining the newest methods for gathering tsunami data, McCreery reveals how it all comes together. The first step is assessing the hazard and looking at possible risk in a certain area, then determining the warning level and issuing a warning.

When the PTWC issues a tsunami warning to an area, the reaction to that warning depends on the area’s civil defense department. Plans need to be in place beforehand, McCreery noted, because tsunamis travel quickly. The PTWC issues warnings to Alaska, California, Washington, British Columbia, the Indian Ocean, South China Sea and Caribbean Sea regions for Pacific-wide tsunami threats.

McCreery revealed that as the director of the PTWC he also has been busy writing reports in preparation for the bi-annual meeting of the Intergovernmental Oceanographic Commission. The meeting is a convening of scientists and geophysicists from countries in the Pacific, representing their particular tsunami warning centers. The weeklong meeting, which takes place from Sept. 17 to 22 in Guayaquil, Ecuador, allows the participants to share system information, data and, for those countries with limited resources, to seek assistance with how to better prepare themselves.

“It’s a way to help countries that don’t have many resources recognize what the risks are and ways to deal with them,” explained McCreery.

Fifteen people - seven geo-physicists, three oceanographers, two electronics technicians, an administrative assistant, McCreery and the assistant director -make up the Pacific Tsunami Warning Center staff. The group grew from eight to 15 after 2004.

“We always have two people on duty to respond - people have pagers to be called (in case of an emergency),” said McCreery. “During the Peru event we had seven to eight helping to do analysis and get out messages.”

With the increase in staff came a decrease in working room for the PTWC staff.

“At the moment we’re a bit crunched for space,“McCreery said. “We had to add a temporary building.”

However, a possible move to the Pacific Region Center, a new National Oceanic and Atmospheric Administration building going up on Ford Island, could alleviate this problem.

“The idea is to consolidate all the NOAA offices in one place in Hawaii,” he explained, adding that it would be convenient because the PTWC interacts with other local offices of the NOAA.

McCreery has been at the center since 1993 and serving as director since 1997.

For more information on the PTWC check out their website at www.prh.noaa.gov/ptwc or call 689-8207. The Pacific Tsunami Warning Center is located at 91-270 Fort Weaver Road.