New monitoring system to take guesswork out of tsunami predictions

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Hours after the powerful earthquake that slammed Japan on March 11, 2011, Perry Schmunk stood on the roof of a Tofino resort, on the lookout for a tsunami. As the manager of the hotel, responsible for staff and guests, he had spent the previous night anxiously tracking the threat to his Vancouver Island community.

In nearby Port Alberni, Fire Chief Tim Pley spent the night at his station, waiting for evacuation orders that never came. Communities along the West Coast of North America relied on data collected from far-off buoys to measure the risk – it is an imprecise science.

This weekend, a crew of ocean scientists will cast off from Victoria on an expedition to deploy a new coastal defence program – undersea recorders that act like an antenna to provide B.C.'s coastal communities with a more accurate tsunami warning system.

The monitoring equipment will be plugged into NEPTUNE, the North-East Pacific Time-Series Undersea Networked Experiments, a chain of deep-sea research observatories linked by powered fibre optic cables. The project is directed by researchers from 12 Canadian universities, led by the University of Victoria.

The antenna detects changes in pressure, allowing researchers to measure variations in wave height, explained Kate Moran, director of NEPTUNE Canada. The system is the first of its kind in the world.

"With an array like this, we'll be able to characterize that incoming wave much better," Dr. Moran said.

The antenna will be installed on the seabed about two kilometres deep, 200 kilometres off the west coast of Vancouver Island. It should take the guesswork out of tsunami predictions – but with little time for a warning.

How much time? "Thirty minutes or less," Dr. Moran said.

Mr. Schmunk, who is now Tofino's mayor, said that would be enough time to get people moving to safety. Since the devastating Japanese earthquake and tsunami, his community has installed sirens and an automated telephone warning system.

"A half-hour warning would make a huge difference in getting people to the two muster stations," he said. A little after 8 a.m. on the morning after Japan's earthquake, he watched as the depleted waves reached Cox Bay, an anticlimactic end to the night's vigil. Months later, he met with Japanese officials who shared their lessons from the devastation in their communities. Getting people to respond to a tsunami warning is critical, and he believes a more explicit detection system will help.

In Port Alberni, where a tsunami in 1964 wiped out 55 homes, the new monitoring system is a welcome addition to the community's emergency preparedness, but Chief Pley wants to be sure that the information is linked up so that they can make use of it. "The real test will be, can we turn that message around, will our community accept a direct notice from NEPTUNE and act on it."

The NEPTUNE project is all about connectivity. It allows researchers to listen, sample and measure what goes on in the deep – and since 2009 the data has been flowing back to the public over the Internet. There's even a new app, a free iBook that links to videos and other images recorded from the observatories. Viewers can watch ghostly skates float by, sea pigs march across the sea bed, and a territorial octopus wrestle for control of an abandoned rice cooker.

For Dr. Moran, the most promising aspect of this summer's expedition is a second set of equipment they will deploy: the VerticalProfiler System. The technology will monitor increasingly low oxygen levels in the ocean that may severely affect fisheries and aquaculture.

"For me, the ability of this network to do long-term measurements of the ocean waters, that's the most important aspect of this network," she said. There is also rising acidification which has been linked to the amount of carbon in the atmosphere. Both issues can have an impact on the food chain.

"Understanding these issues so we can make better decisions will be one of the best things coming out of NEPTUNE," she said.