Roszan Holmen

News staff

Trawlers stumbled upon it accidentally off Vancouver Island’s coast .

Dredged up from the sea floor, half a ton of yellowish ice filled their nets, taking both the fishing and scientific community by surprise.

“It was just astonishing,” said Ross Chapman, the lead investigator in a project to study the mysterious mounds of ice. 

Some five years later, he and his team of international engineers, geophysicists, ecologists and  biologists have high-tech surveillance equipment trained on the frozen gas hydrates (comprised mainly of methane) 24/7. 

Chapman’s proposal — to study where and why the methane ice forms and how long it lasts —  was one of a handful selected by Victoria-based NEPTUNE Canada, dedicated to researching the ocean depths. 

Last week, NEPTUNE crews returned from their month-long mission to install dozens of sensors and probes along the sea floor, off the West Coast of Vancouver Island. 

Frozen methane is a source of growing concern and interest for scientists, governments and oil companies around the world. While some fear rising temperatures will speed its release into the atmosphere, others, such as the Geoscience Centre in Sidney, are investigating its potential as a source of fuel. 

“Methane is perhaps 100 times more potent as a green house gas than Co2,” said NEPTUNE’s project director Chris Barnes. 

Frozen methane in the Arctic permafrost gets most of the media attention while methane off the coast is “out of sight, out of mind,” he said.

“In the bigger picture, one really needs to be worried because there are probably far more hydrates in the marine realm than in these relatively small permafrost areas.”

In the ocean, methane solidifies under a certain temperature and pressure. It occurs extensively along continental margins in many parts of the world and has been discovered to run from B.C. down to Oregon. 

Just how big the deposits are, however, nobody knows.

Also unknown is how global warming will affect the gas hydrates.

“We’re not sure which way it will go,” said Mairi Best, NEPTUNE’s associate director of science, who just returned from the month-long sea voyage.

While warming oceans could cause the methane to bubble to the surface, rising sea levels could also counteract the temperature change.

Chapman’s research takes place at Barkley Canyon, an underwater valley cut by ancient rivers 100 kilometres off the coast. While methane is usually frozen in the subsurface, here it juts out in the form of icy mounds.

Among the many probes, sensors and cameras installed by NEPTUNE is a machine named Wally.

Wally is Chapman’s main “methane sniffer.”

“He’s kind of a myopic little fellow that can’t see very far,” said Chapman, admitting Wally’s taken on a real personality in the minds of the whole crew.

Wally is a crawler that’s tethered to a track and designed at Jacobs University in Germany.

Equipped with a light and webcam, Wally is trained to respond to the unexpected, such as seismic events.

Operators will send Wally on a mission to check out how the change has effected the methane structures.

Wally’s also equipped with a number of sensors to measure methane, temperature, water flow, and salt concentration.

The data is continuously streamed to NEPTUNE’s headquarters at the University of Victoria. 

rholmen@saanichnews.com