The sill depth is about 4600 m and the deepest sections near the sill are less than 20 km wide. We plan to investigate the flow of AABW through the Vema Channel and its modification by mixing using a hierarchy of numerical ocean models. The ultimate goal is to build a regional high-resolution model of the Rio Grande Rise region. However, to focus on specific physical processes we use idealized model configuration as well. Here we show the modification of a deep channel flow by bottom friction.
Narrow passages affect the deep and bottom water transport by focusing and accelerating the flow.
Hydraulic effects play a major role in controlling the volume flux but classical rotating hydraulic theory does not include bottom and interior friction. Observed current profiles show deviations of the mean velocity vector consistent with Ekman veering at the NADW-AABW interface and at the bottom. Temperature sections show a remarkable cross channel asymmetry and a wedge-shaped deep thermocline. Click for original size. Vertical sigma-coordinate with increased resolution near the bottom.