Example of a global surface mooring.

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Example of a global surface mooring.

Global Surface Moorings

The global surface mooring will support sensors at the air-sea interface, on the instrument frame at the end of the chain termination, and fixed instruments distributed along the mooring cable down to 1500 meters.

On the surface will be a modular buoy with a tall, low-drag tower and deep keel. The tower is a monopole and provides for instrument mounting at 5 m above the waterline. A circular crash bar below the instrument mounting area helps to prevent damage to instruments from impact. For power generation, two vertical-axis wind generators are mounted at about 3 m heights on the tower, and solar panels are mounted near the buoy deck.

The buoy will be approximately 8-9 m in overall height with a foam flotation section about 2.8 m in diameter. Unlike typical surface buoy designs that are “bi-stable,” or capable of floating upside-down, this buoy will be designed to self-right. This will be achieved by the placement of heavy batteries low in the buoy’s extended keel. The surface buoy will provide sufficient room for electronics and, when so equipped, the fuel cell power system, in the main well housing.

The global surface moorings will be a low-scope, inverse catenary style mooring consisting of the surface buoy, electromechanical universal, 10-m electro-optical-mechanical (EOM) section, acoustic transducer/instrument frame, special wire rope termination for inductive link, approximately 1000 m of wire rope, a plaited nylon section, a buoyant polypropylene section, glass spheres mounted to mooring chain for backup recovery, dual acoustic releases, and a deadweight anchor. Each Global Array will have upper-ocean and deep-ocean profiling capability.