The Hudson and Raritan Rivers are polluted, while nearly the entire watershed of the pristine Mullica River is protected by the New Jersey Pinelands National Reserve. Barnegat Inlet is the entrance to a long bay fed by several rivers, while Townsend and Hereford inlets serve several small bays that no major rivers feed. The New Jersey coast, with tributaries and ocean depths shown. The gray shaded areas identify the four historical regions of recurrent low dissolved oxygen. Letters designate specific inlets and estuaries discussed in the text.
White lines indicate rivers.
Recurrent Upwelling Under the initial hypothesis that regions of recurrent low dissolved oxygen are related to the three-dimensional structure of upwelling features, several coastal upwelling events were documented off New Jersey each summer between 1993 and 1995. The upwelling response to winds from the southwest usually begins with the offshore transport of the warm surface water and its replacement by a narrow, fairly uniform cold band along a section of the New Jersey coast. This forms a strong temperature front along the offshore side of the upwelled water. Subsequent evolution of the upwelling front occurs as illustrated in the figure. Each year, these upwelling centers are located off the same inlets and estuaries previously identified as regions of recurrent low dissolved oxygen.