A rigid, cable-lowered instrument frame for measuring turbulence and internal waves in the Arctic

The Arctic Internal Wave experiment (AIWEX) is discussed. For 1985, four instrument clusters, each measuring temperature, conductivity, and three orthogonal components of current velocity, were mounted on a 5.5-m-long rigid frame which was lowered by cable to depths as much as 70-m below the ice/ocean interface. The frame was used for both turbulent boundary layer studies in the near-surface mixed layer and for high-frequency internal studies in the Arctic halocline. The instrument clusters comprised fast-response temperature and conductivity sensors and partially ducted impeller-type current meters. Data from each cluster were sampled six times per second, along with frame depth, magnetic heading, and tilt. Deployment of an improved version of the internal wave frame is planned for CEAREX in the Fram Strait in the spring of 1989