be referred to as shelf water (along AB), slope water (along DE) , and 

 Intermediate water . No pure Gulf Stream water was sampled. 



Schematic diagrams were constructed from SXBT profiles through the 

 warm water in order to delineate features of interest to the study in 

 the simplest possible manner. The three sections of 21 and 22 September 

 (figure 12) are characterized by (1) the absence of a mixed layer over 

 the shelf, (2) warm cores (T > 23''C) in the near-surface layer, (3) a 

 cold wedge (T < 10°C) adjacent to the Continental Slope, (4) multiple 

 temperature inversions near the bottom of the seasonal thermocline, and 

 (5) an isothermal bubble (14.1°C) at the seaward end of the northernmost 

 profile. 



The three sections were repeated on 7 October (figure 13) and are 

 characterized by (1) a mixed surface layer at all stations, (2) warm 

 cores (T > 20''C) in the near-surface layer, (3) the absence of cold water 

 (T<10°C) against the shallow portions of the slope, (4) temperature 

 inversions near the bottom of the seasonal thermocline, and (5) an iso- 

 thermal bubble (14.1''C) at the seaward end of the southernmost profile. 



Comparison between the two sets of profiles is difficult, because the 

 small dimensions and complexity of the above features make delineation 

 difficult although station spacing was only 7.4 kilometers. In general, 

 (1) the thickness of the mixed layer was greater in deepwater than it was 

 over the shelf, (2) the warm core cooled from greater than 23°C to about 

 20"*C, and (3) the cold wedge disappeared from all but the southernmost 

 section in October. 



The near-surface thermal structure in the warm water ( i 21°C) differed 

 from that of the surrounding cold water ( < 19°C) in two respects. First, 

 a subsurface temperature maximum was observed at 70 percent of the warm- 

 water stations as compared to a maximum in only 17 percent of the cold- 

 water stations. Secondly, zero layer depth was observed at only 10 per- 

 cent of the warm-water stations as compared to zero layers in 58 percent 

 of the cold-water stations. Occurrences of subsurface temperature maximum 

 and zero layer depth in the boundary between the warm and cold water were 

 37 and 31 percent, respectively. Approximately 86 percent of warm-water 

 stations and 14 percent of cold-water stations were made in water deeper 

 than 500 meters, while 8 percent of the warm-water stations and 83 percent 

 of the cold-water stations were made in water shallower than 150 meters. 



The relationship between thermal structure and water depth for each 

 water regime is given in table 1. The relatively high percentages of (1) 

 warm water with a subsurface temperature maximum in deep water and (2) 

 cold water with zero layer depth in shallow water are of particular 

 interest. 



Two additional schematic diagrams are included to provide further 

 details of features described above, A section made on 7 and 8 October 

 between 36''29 'N,75°04'W and 35''54 •N,73°33'W (figure 14) shows that the 



