Primary Node (PN01D) at the Coastal Endurance Oregon Shelf Cabled Benthic Experiment Package (BEP) site provides power and communications to the Coastal Endurance Oregon Shelf Cabled infrastructure, including a low-voltage node and a low-power jbox. The Coastal Endurance Oregon Shelf BEP site is located on the Continental Slope, approximately 550 meters deep. The Continental Shelf-Slope area off the Oregon coast is a highly productive, dynamic upwelling environment. Upwelling brings nutrients to the surface sparking primary production and fueling the food web. In recent years, upwelling has also brought onto the shelf hypoxic, low oxygen, waters that can be harmful to organisms in the area. By sampling in this area, the OOI seeks to gain better insight into upwelling dynamics of this system.

As with other Primary Nodes, PN01D rests on the seafloor and is connected to the land-based shore station in Pacific City, Oregon via fiber-optic cables. Primary Nodes convert high power from the shore station to a lower power and distribute that power and communication to junction boxes within the Cabled Array through their science ports. Primary Nodes also receive data and communications from the junction boxes which they transmit back to shore.

This particular Primary Node, PN01D, provides power and bandwidth to the Oregon Shelf Cabled Benthic Experiment Package.

The Oregon Slope Base Primary Node (PN01A) is located adjacent to the continental slope off the coast of Oregon at a water depth of approximately 2,900 meters. This site provides power and bandwidth to junction boxes hosting seafloor geophysical sensors for detection of seismic events associated with earthquakes along the Cascadia Subduction Zone and within the accretionary prism. It also provides power and bandwidth to Shallow Profiler and Deep Profiler moorings with a complementary set of seafloor sensors. The coastal region of the Pacific Northwest is a classic wind-driven upwelling system where nutrient-rich deep waters rise to replace warmer surface waters. The result is a large increase in marine productivity that ranges from phytoplankton to fish to marine mammals. Near bottom fauna are periodically negatively impacted by the flow of deep waters with very low oxygen concentrations (hypoxia events), and upwelling of corrosive, acidified waters onto the continental shelf.

As with other Primary Nodes, PN01A rests on the seafloor and is connected to the land-based shore station in Pacific City, Oregon via fiber-optic cables. Primary Nodes convert high power (8 kW) from the shore station to a lower power (375 v) and distribute that power and communication to junction boxes within the Cabled Array through their science ports. Primary Nodes also receive data and communications from the junction boxes, which they transmit back to shore.

This particular Primary Node, PN1A, provides power and bandwidth to all Slope Base Cabled infrastructure, including:

• Oregon Slope Base Shallow Profiler Mooring (RS01SBPS)
• Oregon Slope Base Deep Profiler Mooring (RS01SBPD)
• Oregon Slope Base Seafloor (RS01SLBS)

The Axial Base Primary Node (PN03A) is located near the base of the Axial Seamount at the far western edge of the Juan de Fuca tectonic plate, ~2,600 meters deep.

The Axial Seamount is far from the continental shelf (>350 km) and represents an open-ocean or pelagic site in the continuum of observing scales represented in the OOI’s cabled array. Here, large-scale currents including the North Pacific Current, the subpolar gyre and the northern end of the California Current interact. These currents transport heat, salt, oxygen, and biota, all of which are crucial to the region’s ecosystem. However, their variability arises from forcing as varied as tides and winds to interannual (El Niño) to decadal (Pacific Decadal Oscillation) timescales.  This area is also impacted by undersea eruptions in the form of megaplumes, and most likely by internal tides due to the steep walls of the seamount. PN3A provides power and bandwidth to an array of moorings and seafloor instrumentation, as well as to Primary Node PN3B at the summit of Axial Seamount.

As with other Primary Nodes, PN3A rests on the seafloor and is connected to the land-based shore station in Pacific City, Oregon via fiber-optic cables. Primary Nodes convert high power from the shore station to a lower power and distribute that power and communication to junction boxes within the Cabled Array through their science ports. Primary Nodes also receive data and communications from the junction boxes which they transmit back to shore.

This particular Primary Node, PN3A, provides power and bandwidth to all Axial Base Cabled infrastructure, including:

• Axial Base Seafloor (RS03AXBS)
• Axial Base Deep Profiler Mooring (RS03AXPD)
• Axial Base Shallow Profiler Mooring (RS03AXPS)