entrainment of shelf water by the eddy. Also, comparison 

 of this XBT transect with the Experimental Gulf Stream 

 Analysis N-69 for 4-6 December 1975 produced by the 

 NESS from data obtained from the NOAA-4 satellite 

 thermal infrared VHRR showed good agreement with 

 regard to position and shelf water entrainment. 



Middle Atlantic Bight Transects 



The Gulf Stream crossings were determined in the 

 same manner as discussed earlier in the Cape Hatteras 

 section, that is, the north wall is located where the 15°C 

 isotherm is encountered at 200 m. This location is usual- 

 ly reflected also by increases in surface temperature and 

 salinity. Also the same comparisons between satellite 

 data and XBT data were made as previously discussed. 



Gulf Stream.— In 1975 the Gulf Stream was crossed 

 on 13 occasions (see Table 9 and App. Figs. 47, 49, 51, 52, 

 58 through 64, 66, and 67) by SOOP vessels in the Middle 

 Atlantic Bight. 



Table 9. Gulf Stream crossings in the Middle Atlantic Bight by 

 SOOP vessels in 1975. 



Table 10.— Cold cell crossings in the Middle Atlantic Bight 

 area by .SOOP vessels in I*(7.5. 



Cold Cell. — The importance of the formation, struc- 

 ture, and modification of the cold cell was discussed 

 earlier in the Cape Hatteras section and will not be 

 repeated here. 



In 1975 there were 15 crossings of the cold cell in the 

 Middle Atlantic Bight by SOOP vessels (see Table 10 

 and App. Figs. 47, 49, 51 through 56, and 58 through 64). 

 Some of these transects were of crossings of winter water 

 and not the cold cell feature, but were included in the 

 cold cell section because of the importance of the winter 

 water to the minimum temperature of the cold cell. 



For purposes of discussion, nine of these observations 

 that have occurred in the same geographic area have 

 been grouped into one transect. This track has been 

 designated the MORMAC transect because it is the 

 track used by Moore McCormack Line ships and closely 

 follows a line between New York and Bermuda (Fig. 1). 



Figure 1 summarizes the changes in depth and 

 temperature that occur in the cold cell throughout the 

 year. The cold cell ranged in depth from a minimum of 40 



m to a maximum of 90 m and randomly expanded and 

 contracted its extent over the bottom. 



The cold cell consistently warmed throughout the 

 spring, summer, and into early fall when the fall over- 

 turn again began to cool the water column. 



The random movement of the cold cell across the bot- 

 tom could be the aftereffect of calving or the interaction 

 with the SSF which, in turn, was responding to Gulf 

 Stream eddies that may have been passing through the 

 slope water adjacent to the MORMAC transect. 



In March (App. Fig. 47) the winter water was <6°C 

 between stations 1 and 6 while up on the continental 

 shelf. 



In April (App. Fig. 49) the water was well mixed with 

 temperatures <7°C on the shoreward end of the transect. 

 The cell structure was only beginning to form at this time 

 of the year and was evident with the slight stratification 

 of the isotherms in the near-surface water. 



In May (App. Fig. 51) the cold cell was well developed. 

 Temperatures at the bottom were still <6°C for the most 

 part. The cell structure was on the continental shelf with 

 a slight extension seaward over the shelf break. 



There were three crossings of the cold cell in June 

 (App. Figs. 52, 53, and 54). The first occurred 11 June 

 and showed a well-developed cold cell with minimum 

 temperatures slightly <7°C. The cold cell was well 

 defined because of the strong stratification above and 

 seaward of the cell. The second crossing occurred on 17 

 June at a more oblique angle to the cell structure, hence 

 the exaggerated cell-like structure in Appendix Figure 

 53. At this time, the minimum temperature was still 

 slightly <7°C, but there was an increase in temperature 

 at the bottom between stations 22 and 23 which might be 

 accounted for by an intrusion of warmer water from the 

 shoreward side of the cell structure or just the angle at 

 which the cell was transected, possibly along a lobe or 

 meander of the cell. The third crossing occurred on 22 

 June and was a much more detailed transect. In this 

 transect the entire cell structure has not been transected, 

 but rather only the main core of the cold cell containing 

 the minimum temperature. In this transect, as with the 



