As for where to put the network, Delaney and his collaborators suggested the Juan de Fuca tectonic plate, a roughly triangular piece of crust that juts out into the Pacific from the northwest coast. There they would be able to observe several important processes—the formation of new seafloor, volcanic eruptions, the movement of nutrients from deep to shallow waters, and earthquakes.
Delaney and his partners targeted two sites on the plate as promising places to install their first instruments. One was Hydrate Ridge, selected for its large methane deposits and the unusual chemosynthetic organisms that thrive on top of them. Methane is a potent greenhouse gas, so scientists are interested in how it might be released from the ocean bottom. It is also the main component of natural gas; the Department of Energy is investigating whether the fuel can be mined from humongous deposits under the seafloor.
The second spot was Axial Seamount, an active underwater volcano, along with its associated hydrothermal vents, where the team could study the transfer of minerals from beneath the seafloor into the water and access hardy microbes that thrive in the vent fluids, which can reach 250 degrees Fahrenheit. During eruptions, they might be able to collect even stranger microorganisms that live in the scorching depths of Earth’s crust.
In 2000 Delaney’s group submitted the plan to the National Oceanographic Partnership Program, a collaboration of federal agencies involved in ocean research. The idea had the backing of Mike Purdy, then director of ocean sciences at NSF. Purdy had seen firsthand the limitations of existing tools. He knew that ships were great at collecting data from different locations, but when they returned to the same spots a year later, conditions were often wildly altered.
“We need a new approach to understand changes over time,” Purdy said. Delaney’s cabled observatory addressed that. And bringing power lines from shore would solve the problem of seafloor sensors whose batteries went dead, something Purdy had experienced himself.
Smaller projects already under way were proving that the deep-sea network concept could work. Scientists at the Monterey Bay Aquarium Research Institute in California had laid a 32-mile cable from shore to a site off the coast, testing power supplies, data cables, and instruments. A team at the University of Victoria in British Columbia had developed a cabled installation to study the physical and chemical properties of the local ocean.
Delaney’s proposal would dwarf those projects. Purdy hoped to fund the new ocean observatory through an account that NSF maintains for game-changing scientific infrastructure. But to win approval, the program would have to cover more than just the Pacific Northwest coast. Over nearly a decade, Purdy and his successor, Larry Clark, gathered recommendations from hundreds of researchers on what an ocean observing system should do and which sites would be best to add.
In 2009 the agency settled on a design that included not only Delaney’s cabled network at Juan de Fuca but also a wireless, satellite-linked network off Cape Cod to study the transition between shallow continental-shelf waters and the deep ocean, as well as sensor-packed moorings at four sites in high-latitude waters that are rich with aquatic life.
That fall NSF agreed to provide three-quarters of a billion dollars for construction and initial operation of the Ocean Observatories Initiative—a staggering sum in the modest-budget world of ocean exploration. By November Delaney had contracted marine operations company L-3 MariPro to build the backbone of his deep-sea network, including the seven nodes that will power instruments and transmit data through the system.
Finally, in the late spring of last year, the cable-laying vessel Dependable began stringing 560 miles of fiber-optic line from Pacific City, Oregon, to Hydrate Ridge and Axial Seamount. A few months later, with cable installation still in progress, Delaney and his team set out from Seattle aboard the Thompson to test a node in the water.
Trip to the Ocean Floor
The Thompson winds through Puget Sound and then out into the Strait of Juan de Fuca, stopping in Victoria to pick up Ropos, a remotely operated vehicle (ROV) whose motions can be controlled from the ship. The plan is for Ropos to carry a node—a 3,000-pound, yellow and orange watertight box about the size of a refrigerator—to the shallow bottom of the strait to test the plugs and connections that will link it to the cable and to scientific instruments.
The morning is chilly, with fog as impenetrable as the dark waters below. Ropos comes to life on the port-side deck as the vehicle’s engineers run their pre-dive check. The robot’s camera scans up and down, then side to side. One by one its lights flicker on and off at the command of technicians in the control room.
Crew members lower a titanium cage, which will serve as a protective frame for the node, down to the seafloor. Next Ropos must go down to unhook the wire used to lower the frame and open its doors so that the node can be placed inside. A crane lifts the robot from its cradle. With camera lenses for eyes and mechanical arms folded against its yellow and black body, it looks like a giant insect poised above the water. The crane drops Ropos in. Its lights pop on and diving thrusters kick into gear. Then it disappears into the gray, trailing the umbilical tether that allows it to communicate with the ship.
About 15 scientists and engineers crowd into the dark control room to watch the ROV’s video feed. Pilot Reuben Mills navigates Ropos to the frame and begins unscrewing shackles connecting it to the wire, clearing the way for the node. No one speaks. The assembled researchers bite their lips, following Ropos’s smallest movements. Its two-fingered mechanical pincer grabs the pin of a shackle in an attempt to undo it, then slips off.
Jonathan Lee, another Ropos pilot, explains that if a sensitive manipulation fails on the first try, the pilot can end up in a “death spiral,” overcompensating on every movement due to nerves and sending Ropos’s arms in circles around their target. Mills keeps his cool, though, and after a few hours of painstaking work, the frame is ready. Ropos collects the node from the deck and heads back down to insert it into the frame, this time with Lee piloting.
Although the vehicle is returning to the spot it left earlier in the day, strong tidal currents are flowing now, and even with his thrusters at full power, Lee struggles to hold the ROV in place. Delaney unhappily eyes the blizzard of plankton and detritus zooming by on the video feed. “It looks like warp 6 down there,” he says. “This could be a serious problem.”
On the bottom, visibility fades to a few feet; everything beyond is a swirl of sediment. After a grueling two-hour battle against the current, Ropos reaches the frame. Unable to see clearly, Lee tries to maneuver the node into its slot by feel, without success. The group opts to wait for conditions to improve, but three hours later, the situation is not much better. Ropos operations manager Keith Shepherd slides into the pilot seat for one final attempt and somehow manages to drive the node into its frame. Deciding not to push its luck, the team abandons the remaining tests and hauls its equipment out of the turbulent water.
And that is just one node. Installing seven of them, and connecting them all to the main cable, will be a major undertaking. Delaney estimates that it will take two months at sea to complete the job.