A MOORED PROFILING INSTRUMENT

Abstract The specifications and performance of a moored vertical profiling instrument, designed to acquire near-full-ocean-depth profile time series data at high vertical resolution, are described. The 0.8-m-diameter by 0.4-m-wide device utilizes a traction drive to propel itself along a standard mooring wire at a speed of ∼0.3 m s−1. The average power required to profile at this speed is 1–2 W; the present sensor suite and controller draw about 1.5 W. Based on these figures, the instrument’s battery capacity will support approximately 1 million meters of profiling. Instrument actions are regulated by an onboard microcontroller, allowing complex dive programs to be carried out. Oceanographic and engineering data are recorded internally on a hard disk interfaced to the controller. The measurement suite thus far deployed includes a CTD for deriving ocean temperature and salinity profiles, and an acoustic current meter that returns ocean velocity profile data. Addition of other oceanographic sensors is antic...