Flow structure and multiple-scale topography in the coastal ocean.

Coastal upwelling has been the focus of both modeling and observational efforts on New Jersey's inner shelf as part of the NOPP/ONR funded efforts in the vicinity of Rutgers University's LEO-15. Particular effort has focused on an upwelling center which develops as winds relax immediately to the north of a topographic high. The spin-up of the upwelling center appears to be related to a strong near-shore upwind jet which veers offshore as in impinges on the topographic high and feeds the upwelling center with cool water. While the both the topography and the upwelling center have a common 25-50 km length scale, superimposed on this larger topographic scale is smaller scale associated with oblique sand ridges. These sand ridges modulate water column depths by up to 25 percent and have a horizontal length scale 5-10 km. The ridge/swale topography is significantly more pronounced over the topographic high. Thus the multiple-scale topography along the New Jersey coast is characterized by relatively smooth topographic lows and significantly rougher topographic highs. Over the past three years shipboard and autonomous ADCP surveys have completed numerous repeated transects over both topographic features. The influence of this multiple-scale topography on detided depth averaged and depth dependent flows are discussed based on a statistical description of the entire data set and on event scale flow features.