Underwater observatory captures coastal upwelling events off New Jersey

A third summer of coastal upwelling observations was recently completed by researchers at LEO-15, the Long-term Ecosystem Observatory established in 15 m of water offshore of Tuckerton, New Jersey. Each year, real-time satellite images of wind-driven upwelling events trigger fast-response shipboard surveys to study the subsurface structure of the upwelled features and their relationship to bottom dissolved oxygen (DO) concentrations (Figure 1). The LEO-15 observations indicate that recurrent up-welling centers develop on the downslope sides of topographic highs and coincide with the historically observed regions of recurrent low DO. Recent modeling suggests that because of the along-shore topographic variations, a cyclonic eddy in the upwelling center forms that may concentrate nutrients, leading to phytoplankton blooms and subsequent reductions in DO as the resulting organic material decays below the thermocline.