The Cold-Water Pathway during an Upwelling Event on the New Jersey Shelf

Abstract

Abstract A comprehensive dataset obtained in summer of 1996 on the New Jersey shelf off Atlantic City is analyzed to determine the pathway for cold water during a period of sustained upwelling. The data include shipboard CTD/ADCP surveys, time series from three across-shelf lines of moorings, and remote sensing. An upwelling event that occurred from 30 June through 10 July 1996 is studied. The event comprised three stages: first, the cold water was upwelled through the bottom layer; second, the onshore flow concentrated in the pycnocline; and third, mesoscale eddylike features developed. During the first upwelling-favorable wind pulse, which lasted approximately 2 days, a northward alongshelf current was generated and the pycnocline outcropped at the surface approximately 5 km off the coast. The northward current occupied the whole water column, and cold water was brought to the coast through the near-bottom layer, in the manner of Ekman dynamics. After that, an alongshelf pressure gradient was set, which...