Turbulence and waves over irregularly sloping topography : cruise report - Oceanus 324

This report documents the work of R/V Oceanus cruise 324, which occurred during May of 1998. This cruise was the field component of the Turbulence and Waves in Irregularly SlopingTopography (TWIST) program. TWIST was part of the Littoral Internal Wave Initiative (LIW)supported by the Office of Naval Research.The objective of TWIST was to sample the background, internal wave and turbulence propertieson the Continental Slope in the Mid-Atlantic Bight. Previous investigations have revealedstrongly enhanced finescale internal wavefields and much more energetic turbulence due tointernal wave breaking above topographic roughness associated with the Mid-Atlantic Ridge. So,an area of steeply sloping ridges and troughs running perpendicular to the continental slope near36˚34'N, 74˚39'W was chosen as the site of the observational program due to its topographicsimilarity to the Mid-Atlantic Ridge.Fíve instrument systems were employed to make observations during this cruise: the HighResolution Profier (HRP), three Moored Profiler (MP) moorings, a Lowered Acoustic DopplerCurrent Profiler/Conductivity, Temperature, Depth (LADCP/CTD) rosette, eXpendable CurrentProfilers/eXpendable CTD (XCP/XCTD), and finally, the shipboard ADCP. The data from theseinstruments (more than 1100 full depth profiles) provide adequate spatial and temporal resolutionto describe the finescale and turbulent processes observed.

Funding was provided by the Office of Naval Research under Grant No. N00014-97-1-0087.