Station Papa Collaborative Expedition Completed

Ten scientists and engineers. Nineteen days at sea. Approximately 620 nautical miles offshore in the Gulf of Alaska. Six successful mooring deployments — three for the Ocean Observatories Initiative (OOI),  two for the National Oceanic and Atmospheric Administration (NOAA), and one for the University of Washington (UW).   

The Station Papa 9 team aboard the R/V Sikuliaq demobilized in Seattle, Washington on May 31 after a 19-day expedition to the Global Station Papa Array, in the Gulf of Alaska. In addition to the recovery and deployment of three OOI moorings (Global Hybrid Profiler, two Global Flanking Moorings), the team successfully completed two mooring recoveries and deployments for NOAA (a surface mooring and noise reference station) and UW (a Waverider, which measures surface waves). The team also carried out shipboard underway sampling, including collection of water samples, to support field calibration and validation of the platforms and sensors in the array.

The Station Papa moorings are outfitted with instruments that measure conductivity, temperature and depth, (CTD) dissolved oxygen, pH, fluorescence, acoustic backscatter (for characterizing zooplankton), and ocean currents.  The Hybrid Profiler Mooring contains two Wire-Following Profilers that house instrumentation. The Wire-Following Profiler moves through the water column along the mooring riser, sampling ocean characteristics at a high vertical resolution over a specified depth interval (310-2,100 meters and 2,100-4000 meters deep). The flanking mooring contain instruments fixed at specific depths along the mooring riser to a depth of 1,500 meters.

“The OOI Station Papa Array was designed knowing that other groups were already contributing substantial assets to the site” said Al Plueddemann, Principal Investigator of the Coastal and Global Scale Nodes (CGSN). “Seeing this collaborative observing effort come together in one joint expedition was gratifying”.

To successfully move around a significant amount of ocean observing equipment involved in six deployments, the team conducted the operation in two stages. The team first deployed the moorings that were loaded onboard the Sikuliaq at Seward, and then retraced their steps to recover the moorings that had been in the water for over a year. (OOI’s global arrays are only turned annually).

The subsurface moorings at Station Papa have various components all important for the collection of scientific data.  The orange spheres provide buoyancy to keep the mooring vertical and instruments at the desired depth. Shown here is the recovery of one of these flotation spheres. Credit: Rebecca Travis ©WHOI.

Station Papa 9 is the second of three nearly back-to-back recovery and deployment expeditions by OOI’s Coastal and Global Scale Node (CGSN) team this spring.  The first was a Pioneer Array expedition, with two legs spanning 8-29 April. The expedition to Station Papa was next.  The third after Station Papa is a nearly month-long expedition to the Irminger Sea Array, which will leave the dock in Woods Hole, MA on June 20.  Said CGSN Program Manager Derek Buffitt,  “Once recovered equipment is brought to shore, we immediately start to tear it down, perform inspections, download data, and start the refurbishment process.  Quick turnaround times like we have had this spring, can make it challenging, but our technicians and engineers are up to the task.  I am very proud of the work the CGSN team performs onshore and offshore.  They are experienced professionals who you can always trust to get the job done.”

More photos and information about the Station Papa 9 expedition can be found at its expedition blog page here. OOI Station Papa data are available from using a variety of access methods described here. The NOAA/PMEL surface mooring is described here, the NOAA Noise Reference Station network is described here, and the UW Waverider is described here.