Current/temperature measurements near the Sigsbee Escarpment from the MMS Desoto Canyon Intrusion Study, 19990829 - 20010906 (NCEI Accession 0002569)

During this study in-situ measurement of currents, temperature, and conductivity were made on a series of tautline moorings near the base of and on the Sigsbee Escarpment. These were supplemented during six of the 24 months of measurements by three Inverted Echo Sounders with Pressure. The primary objective of this project was documentation of near bottom/lower layer dynamics which have been identified as having high current speeds over an extended lower layer water column with near bottom intensification. Observations were often jointly funded by the MMS and BP. Results showed the layer below a nominal depth of 1000 m to have vertically highly coherent motion with a weak shear profile. The dominant process affecting currents at the base of the Escarpment appear to be Topographic Rossby Waves with periods of 8-11 days which moved through the study area in trains that could continue for many months. Current speeds as high as 1.75 kts. were measured 100 m above the bottom in 2000 m water depths.