The Rapid-Sampling Vertical Profiler: An Evaluation

Evaluation of the Rapid-Sampling Vertical Profiler, which was developed for sampling the hydrophysical fields in the upper ocean from a moving vessel, shows that the instrument is useful for near-microscale measurements of temperature and salinity and also for turbulent kinetic energy dissipation measurements with airfoil probes. A depth of 200 meters is reached from a ship moving at 6 knots. The vertical resolution is 3 cm, the temperature resolution is 0.5 millidegrees, the salinity resolution is 0.6 parts per million, and the sigma-t resolution is 0.0004. (The estimates given for resolution are 99% confidence limits on series of 3-cm samples.) The instrument falls with a speed uniform within 20% in an orientation within a few degrees of vertical. Vibrations within the dissipation range of turbulence are sufficiently small to permit the measurement of turbulence with airfoil probes in many regions of the ocean.