Epicenter of U.S. tsunami warning system at home in the Mat-Su

PALMER — An automated voice issued a warning Friday, and the staff of the National Tsunami Warning Center in Palmer tensed.

Watch stander Peggy Johnson and the center director Paul Whitmore pulled up displays for two waiting computers, and data rapidly scrolled across eight different monitors. The two passed information back and forth between them, comparing the readouts of the magnitude of the earthquake, the depth in the earth’s crust and other factors. Then they logged the earthquake in the system.

“Well, there you go,” Johnson said.

The tension eased.

The 4.9 earthquake that tickled a network of seismic instruments was located near the Commander Islands, off the coast of Kamchatka, Russia, and wasn’t likely to cause a tsunami big enough to impact the United States. No warning needed.

“This one’s too small, so we won’t for this one,” Johnson said.

The moment passed so rapidly that another watch stander, Paul Huang, missed it entirely when he stepped out of the center’s central room for a moment.

“Yeah, where were you?” Johnson said

“I was brushing my teeth,” Huang said.

“Oh … that’s why I don’t brush my teeth,” Johnson joked.

Huang asked if they could turn up the volume for the alarm.

Suddenly, the automated warning sounded again. A magnitude 3.3 quake rumbled the seafloor off of Nicaragua’s Pacific coast. Huang and Johnson jumped on the computers and traded the same numbers Johnson and Whitmore had moments earlier, with the short back-and-forth ease of habitual co-workers.

“Depth of 155,” Johnson said.

“No, you’re wrong,” Huang said.

“You’re wrong,” Johnson said, in an exaggerated sing-song taunt.

“It’s 55,” Huang said. “There’s no way it’s that deep.”

He wheeled his chair over to peer at her screen. They looked at her data together, then at his data, trying to figure out the discrepancy. They had too many earthquakes on their screens: the data didn’t match because it was from the first earthquake, which happened about seven minutes before the Nicaragua quake. The Nicaragua quake was 155 meters deep.

“See? I was right,” Johnson joked. “A little friendly competition.”

Landlocked Palmer isn’t a place that immediately springs to mind in connection with tsunamis, the giant waves that can pour into coastlines after earthquakes. The local ecosystem is punctuated by the aftermath of the legendary 1964 Good Friday earthquake: a two-foot lowering of the Palmer Hay Flats as a result of the quake transformed them from farmland into marshland. But tsunamis?

“We have extremely low tsunami risk here, which is why we’re here,” said intern watch stander Summer Ohlendorf, who conducted part of a recent tour of the building for the Frontiersman.

The center’s Felton Street location is also a legacy of the 1964 quake. Three observatories established in Alaska as a result of that quake were eventually consolidated into the Palmer office. The center’s jurisdiction covers the entire mainland U.S. Pacific coast, plus the U.S. Virgin Islands and Puerto Rico, though those areas will eventually be moved to the jurisdiction of the Pacific Tsunami Warning Center, based in Hawaii.

“It’s a little crazy, say, if you live in San Diego, to think that there are people in Alaska watching out for you, but that’s the way things kind of naturally developed,” Ohlendorf said.

The center runs 24 hours per day on nine-hour shifts (shifts overlap to provide by an hour to provide for transfer), and two watch standers receive data from networks of sensors maintained by universities, governments, and other institutions all over the world. When an earthquake registers in the system, standers, who are also geologists and seismologists, come to the computers to evaluate possible tsunami risks. Watch standers said they are able to tell within a few moments whether the risk is severe enough to alert the public. From there, word goes out to the public via weather band radio, and, more recently, social media and cell phone text messages.

“The rest of the time, we have developmental projects we’re all working on to either streamline the operations of the center here or to perform kind of auxiliary tasks that would help out in the case of a warning,” she said.

Apart from receiving data from other institutions, the center also builds its own sensors, ranging from seismographs to radar-based water-level monitors.

Two technicians — Scott Langley and Michael Burgy — design the sensors, and then fly as far as Amchitka, in the far western Aleutians, to monitor and maintain them. Contracts for specially constructed parts go out to local metal fabricators, Langley said.

The latest seismographs are much more advanced than the days of what Huang joked was “voodoo seismology” or using pen, paper and mathematics to predict the seismic waves’ progress through the earth. For that matter, they’re much better than the seismographs used in the more recent past, Burgy said.

“It’s like going from a single AM radio in your pick up truck to surround sound in your home,” he said.

All the data goes into one of two mathematical models used to predict the point at which a tsunami will arrive at certain land masses. Older models can predict a simple time and region of location, while newer models are able to predict different levels of flooding at various points along the coast.

That distinction can be important. The Japanese tsunami of 2011 killed a single person in Crescent City, California, which also suffered massive damage from the 1964 Good Friday quake, because it rests at the end of a narrow submerged ridge stretching for miles across the Pacific, which dead ends at the harbor, and amplifies the effects of tsunamis, said Kara Gately, the center’s senior watch stander.

The center is also working to produce a system called T-Web specifically for emergency managers, expected to go live in 2016, which combines the inundation data with Google maps to help emergency mangers decide whether to order people out of potentially affected areas or not, Gately said.

“You’d have to have a login to access that,” she said.

Despite the center’s near global reach and national significance, it’s still connected to the local community, Ohlendorf said. When a 7.1 magnitude quake struck Southcentral Alaska in late January, the center brought on additional people, not because it was an emergency (the center didn’t issue a tsunami warning, its most serious advisory, as a result of the January quake), but because the phone was ringing. Reporters from CNN and local folks alike wanted to know what was going on, Ohlendorf said.

“A lot of the local residents actually call when they feel an earthquake, because they know we’re monitoring things all the time,” she said.

The center will hold an open house from 1 p.m. to 4 p.m. on Saturday, April 2 with an earthquake simulator, a wave tank, information about warning signs and other activities for all ages. The activities are the culmination of Alaska Tsunami Preparedness week, which began Monday.

A tsunami emergency broadcast system test is also scheduled for 10:15 a.m. on Wednesday.

The Center also holds regular tours for the public at 1 p.m., 2 p.m., and 3 p.m. every Friday.

In the event of an earthquake or tsunami warning, officials urge coastal residents to evacuate to nearby high ground or inland and stay there until instructed otherwise, according to www.tsunamizone.org, the official Web site of Tsunami preparedness week.

Contact reporter Brian O’Connor at 352-2270, brian.oconnor@frontiersman.com, or on Twitter @reporterbriano.

Correction: An earlier version of this article misstated the name of the National Tsunami Warning Center director and the times of the open house.