Oregon State University will launch a fleet of undersea gliders in 2012 and deploy new moored ocean-observing platforms beginning the following year as part of the $386 million Ocean Observatories Initiative.
The OOI is a major marine science infrastructure project funded by the National Science Foundation and announced two years ago.
A significant piece of the OOI’s “Endurance Array” will be located off the coast of Newport, Ore., which increasingly has been under scientific scrutiny because of issues ranging from hypoxia and “dead zones” to climate change impacts, subduction zone earthquakes, tsunamis, harmful algal blooms, wave energy potential, ocean acidification and dramatic variations in some upwelling-fed fisheries.
One of the other institutional partners on the project is the University of Washington, which this summer led an effort to lay undersea cable off the Northwest coast that will provide power for the moorings and seafloor instrumentation as part of the OOI’s Regional Cabled Network. During the past summer, OSU’s College of Oceanic and Atmospheric Sciences has been designing and testing an array of equipment that will be deployed beginning in the spring of 2013. Testing of the new gliders will begin this fall.
“We’re in the final stage of testing many of the instruments and we’re ready to go,” said Robert Collier, OSU’s program manager for the initiative. “This project is really unprecedented. We’ll be monitoring the ocean in ways it has never been looked at before, and sharing the data in real time with scientists, managers, educators and the public around the world.”
The OOI will result in a networked infrastructure of science-driven sensor systems to measure the physical, chemical, geological and biological variables in the ocean and seafloor. The idea, according to project director Tim Cowles, a former OSU oceanographer, is to provide greater knowledge of the ocean’s interrelated systems, which is vital for understanding their effects on biodiversity, ocean and coastal ecosystems and climate change.
Creating a network of sensors that can accurately measure the physical, chemical and biological characteristics of the marine environment – and still withstand the rugged Pacific Ocean – is a major challenge, acknowledges Ed Dever, OSU’s systems engineer for the project.
“For one thing, what happens at the surface is different than what is going on along the seafloor,” Dever said, “so we have to have instrumentation that can monitor both. And the water in between is ever-changing. So the mooring sites will be designed in a way that we will be able to measure changes throughout the water column.”
Beginning in the spring of 2013, the first three (of six) mooring systems will be deployed – all off the coast of Newport. The final three will be deployed in 2014 off Grays Harbor, Wash. The Newport sites will be located at one mile, 10 miles and 33 miles offshore, with the outer two sites connected to the undersea cable.
Each site will feature a surface buoy that will monitor the air-sea interface, and measure air and sea surface temperatures, solar radiation, humidity, air pressure and other variables. The site will include a seafloor platform containing its own array of instruments, including sensors to measure dissolved oxygen for hypoxia studies, carbon dioxide levels, pH and nitrogen. Other sensors will actively observe larger plankton and fish, while “passive” acoustic devices will listen for marine mammals. A third instrument array will continuously move up and down through the full water column, tethered to the seafloor.
“The suite of instruments will really allow us to look at what is happening in the ocean and discover when changes occur,” Collier said. “Some of the biological sensors, for example, will be able to model primary production through chlorophyll and light levels, and another will use acoustic backscatter that can estimate zooplankton density.
“However, it’s not these individual measurements that are really new,” Collier added. “It’s the fact that we’ll be monitoring the ocean 24 hours a day, all year long, instead of looking at it periodically from ships of opportunity.”
One limitation, Dever said, is that these mooring sites will be located only off Newport and Grays Harbor, “giving us great vertical resolution, but only two lines of observations spanning the entire coast.” To cover more of the Northwest regional ocean, the OSU oceanographers will deploy a dozen new undersea gliders beginning in 2012.
Six gliders at a time will patrol the ocean from the Canadian border to southern Oregon. These sophisticated machines can be programmed to run for 2-3 months from the near-shore to the continental slope and every six hours they will rise to the surface and transmit data to OOI computers via satellite.
Instruments aboard the gliders will record temperatures, salinity, biological production and dissolved oxygen – many of the same measurements being made from mooring instruments. “One difference,” Collier said, “is that the mooring platforms will give us a constant look at six places, while the gliders will give us larger views of the coast ocean from Oregon to Canada.”
The gliders are incredibly productive, said Jack Barth, OSU’s project scientist.
“In more than half a century of work, OSU scientists have recorded about 4,000 profiles of the near-shore from ships,” Barth said. “During the past five years, the handful of gliders we already utilize have logged more than 156,000 profiles – nearly 40 times what six decades of shipboard studies have provided.
“That’s pretty amazing, when you think about it,” Barth added. “Each year alone, we log more profiles than have ever been recorded via ship off Newport. And that will only increase as the Ocean Observatories Initiative reaches fruition.”
The Ocean Observatories Initiative team at OSU has grown to 17 staff scientists, engineers and technicians, and the university expects to add even more people to operate the Endurance Array over the next few years, Collier said.
“We are excited to be so close to getting this into the water,” Collier said. “This dream we’ve been developing for more than a decade will soon be a reality.”