A Compliant Surface Mooring System for Real-Time Data Acquisition

The Physical Oceanographic Research Team at the University of New Hampshire is monitoring seasonal changes in the water properties of the Gulf of Maine with four instrumented surface mooring systems which measure temperature and conductivity at 50 meter intervals to 270 m. A surface based microprocessor controlled data logger collects and telemeters data in near real time via the GOES satellite. Sensors attach to an electromechanical cable which is hardwired to the surface buoy and mounted electronics. Solar energy provides total system power. A special electromechanical connection provides the critical union of cable to buoy. Compliant rubber tethers installed in the mooring line significantly improve surface buoy stability and together with a commercial bend limiter reduce subsequent bending strain in the cable. Four moorings were deployed in August 1986 for a 13 month duration. Three systems have survived the harsh Gulf of Maine winter and still operate with near perfect data records. Two of these moorings were serviced in April 1987 and conditions evaluated. The fourth broke loose in February after returning seven months of data.