Miniature Acoustical Sensor for Fast In Situ Measurements of Currents and Simultaneous Density Fluctuations in the Same Water Sample

This paper deals with a newly developed field proven acoustical sensor, which is particularly well suited for the collection of such important pairs of data like current shears and density gradients simultaneously determined in the same sample of water, e. g. in the small scale turbulence regions of the internal wave field or in the bottom boundary layer of the ocean. It is also good for current measurements strongly depending on high zero point stabilities and requesting current resolutions of 1 mm/s or even better. The sensor has been successfully operated in the North Atlantic Ocean, delivering many profiles in real time while mounted on a free falling torpedo shaped platform. Besides the description of the sensor, results from field trials will be reported on.