Velocity measurements from a moored profiling instrument

Velocity profile measurements from a recently-developed moored profiling instrument are discussed. The WHOI Moored Profiler uses a traction drive system to propel itself along a standard subsurface mooring cable at a nominal speed of 0.3 m s^-1. The instrument´s onboard controller supports complex sampling scenarios, limited chiefly by the configuration of the mooring and the capacity of the battery. The vehicle has thus far been equipped with a CTD and an acoustic travel-time current meter; data from the latter are examined. As part of this assessment, comparisons are made between velocity profile data obtained with moored profilers and those obtained from an expendable current profiler, the High Resolution Profiler, and a lowered acoustic Doppler profiler. The authors conclude with a summary of possible applications for the new instrument