Ocean observatories initiative coastal surface mooring technology

The Ocean Observatories Initiative (OOI) is directed to operate and maintain arrays of moored and mobile assets in six locations around the globe. These locations include two coastal arrays off of the east and west coasts of the United States and four global arrays in the Southern Ocean, Argentine Basin, Irminger Sea, and North Pacific. These arrays are currently operational, supplying oceanographic data to the scientific community in near real time. The moorings deployed at these arrays include a number of technological innovations in the field, resulting in some of the most complex mooring systems in use. There are several different classes of moorings in use by the OOI project. This paper will detail the primary systems of the Coastal Surface Moorings (CSMs) deployed off the east coast of the United States at the OOI Pioneer Array. The innovative systems designed into a CSM include networking and telemetry, power storage and generation, and electromechanical systems that span the distance from the seafloor to the surface. The mooring configuration includes a surface buoy with instrumentation at the air-sea interface, telemetry systems mounted over 4.5 meters above the sea surface, and power generation systems. A Near Surface Instrument Frame (NSIF) with instrumentation is located 5 meters below the surface. A MultiFunction Node (MFN) with instrumentation, communication, power distribution, and a recoverable anchor assembly is located on the sea floor. There are currently nine single board computers (SBCs), with room for expansion, distributed throughout various locations on the mooring. Several areas of technology had to be developed in order to implement this capability. The SBCs had to be networked together, creating a need for high speed connections, both to shore, and to the sea floor. The number of sensors and computers, and the use of high speed telemetry, translates to a significantly higher hotel power load than a typical offshore moored system. This power requirement led to the development of a power system with enough reserve storage and power generation to maintain operation over 6-month deployments.