High Salinity Core of Slope Water 



p]xten(lin<; parallel to the shelf edpe, and 5 to 

 10 nautical miles seaward from this edge, was a 

 band of hijiher salinity water similar to that re- 

 ported by Bigclow and Sears (l!);i')) and others 

 [Whitcomb (1970) for example]. This band is 

 simply an expression of the impin<renient on the 

 slope bottom of typical North Atlantic Central 

 Water (Iselin, 1936), the surface of which has 

 been freshed by inixin<i: with shelf water. Fol- 

 lowin<r Whitcomb's (1!>70) example for Septem- 

 ber 1967 of defining the core as salinities greater 

 than 3.5.75°/<,„, the defined core did not reach the 

 surface, and its depth range was dependent on 

 whether or not there was an eddy present. 



On section A the core was characterized 

 by an anticyclonic eddy which caused the cross- 

 section of this core to increase considerably. 

 Maximum salinity in the core section of this 

 eddy was 36.2°/„o, and the 35.75°/„„ isohaline ex- 

 tended from about 20 to 375 meters. The defined 

 core was absent on section B north of the eddy; 

 on sections C and D it was found between about 

 70 to 120 meters. Sections E and F were in- 

 fluenced by a large eddy eastward of the sections, 

 thus the defined core extended from about 30 to 

 210 meters and was still increasing in thickness 

 at the end of the sections. The salinity and 

 signia-t profiles .show little evidence for the 

 35.7.5°/oo core intersecting the bottom, although 

 there is an obvious bottom salinity maximum 

 over the shelf break. 



Temperature/Salinity Correlations 



The temperature salinity correlation for water 

 present in the New York Bight during August 

 1974 could be accounted for in terms of the prin- 

 cipal modes described by Hayes (197.5) (figs. 

 25a, and 25b). 



In August 1974 waters from the coastal area 

 and contained within a band extending approxi- 

 mately 40 nautical miles oti'shore had charac- 

 teristics that fell within an envelope with 

 salinities less than 33.5%„ (Envelope A. fig. 

 25a). Note that the lower portion of this enve- 

 lope includes what Hayes called Middle Atlantic 

 Bight Coastal Water. The lower portion of the 

 envelope also represents the cold core previously 

 described. The upper portion of the envelope 

 reflects the warming eflFect of summer surface 

 heating and the freshening efl'ect of spring run- 

 off. 



Water from the centers of the two eddies fell 

 within an envelope with salinities greater than 

 34.0°/„„ (Envelope B. fig. 25a), displaying char- 

 acteristics similar to those described as Regions 

 8 and !» in "Physical Proi)erties of the North 

 Atlantic Ocean," Naval Oceanographic Office 

 Publication #700, Section II (fig. 25b). This 

 etivelope could also be explained in terms of 

 Hayes', Gulf Stream Water, Surface — and Mid- 

 slope AVater, and Deep Slope/North Atlantic 

 Deep Water if allowance weie made for summer 

 warming of his Surface — and Mid-slope AA'ater 

 (fig. 2.5b). 



At the stations between tiio.se founil in the two 

 envelopes the water shows the influence of mix- 

 ing between the envelopes. Station 28 (fig. 25a) 

 is an extreme example of this mixing. The 

 water at the surface shows characteristics similar 

 to that in envelope B; at depths of about 25 to 

 70 meters water derived from the cokl core is 

 encountered, below this the mid-slope water is 

 found. An example of this type of mixing in 

 shallower shelf water can be seen at station 12 

 (fig. 25a). Here the influence of surface water 

 in envelope A is much stronger tlian that in 

 envelojie B. Another example of this type of 

 mixing, in deeper slope water, can be observed 

 at .station 53 (fig. 2.5a). Here the influence of 

 sui face water from envelope A cannot be seen 

 at all, and the influence of the cold low salinity 

 core at the bottom of envelope A is slight. Simi- 

 lar situations are found for .stations 6, 51, 50, 54, 

 55, and 49 around the southern eddy, and for 

 station 26 near the northern eddy. These sta- 

 tions appear to basically represent slope or eddy 

 water with which some shelf water has been 

 mixed. 



Station 29 on the shelf represents intrusion of 

 slope and eddy derived water onto the shelf. 

 This is apparent in the salinities of 35.5°/„o 

 found around 30 meters. 



Circulation 



In coastal waters, where there is adequate 

 fresh water discharge, a slope of the .sea surface 

 downward from the coast offshore is usually at- 

 tributed to the increases in the steric anomaly 

 related to run-off. The resulting dynamic gradi- 

 ent is associated with a steady flow turned to the 

 right (in the northern hemisphere) and thus 

 nearly parallel to the coast. Steady wind drift 

 currents may modify this rough picture (Bum- 



