The adjusted area and predicted adjusted area for the second survey 

 differ by 1.0 which is probably close to the amount by which the Grand 

 Banks eddy was below normal during this survey. The discrepancy 

 existing during the third survey is not the result of an abnormal situa- 

 tion at section U and may possibly arise from the pronounced meander 

 of the Atlantic Current to the right. If, as suggested by Haurwitz and 

 Panofski,^ such meanders are the results of unstable waves, the effect 

 of very large meanders on the boundary in this area would not be 

 forecast by the sea level differences along the Charleston-Bermuda 

 section . 



The temperature distribution found during the June survey along 

 section W and its southward extension is shown in figure 20. The 

 low temperatures over the shelf, which in this case is the Grand Banks, 

 and adjacent to the slope identify the remnants of the Labrador 

 Current and the mixed water respectively. Seaward of the mixed 

 water, beginning at about station 4183, lies the eastward moving 

 water of the North Atlantic eddy. The dip of the isotherms doA\Ti- 

 ward and to the right is indicative of the swift easterly current. In 

 Ice Patrol parlance the cold wall is the steep horizontal temperature 

 gradient at the sea surface which appears immediately to the right of 

 station 4183. Some students of the Gulf Stream sector of the North 

 Atlantic eddy define the cold wall as being indicated by the descent of 

 the isotherm of 65° F (18.3° C) to a depth of 800 feet (244 meters) 

 or more. Figure 20 shows this to have occurred between stations 

 4176 and 4177. Reference to figure 18 suggests an extensive meander 

 of the Atlantic Current southward to the vicinity of latitude 39° N., 

 and a subseciuent return of at least a part of the current to a latitude 

 greater than 41° N. It will be seen, therefore, that the temperature 

 profile presented in figure 20 is not entirely a profile across the Atlantic 

 Current but for a considerable part of its length is a section along the 

 current. There is also evidence of another and probably smaller 

 meander of the Atlantic Current to the right southeastward of station 

 4199. 



Measurements made in 1937 in the area eastward of the Grand 

 Banks have been interpreted * to indicate that the depth of the 

 motionless surface beneath the Atlantic Current in this region is 

 about 2,000 or 2,500 meters. The conclusion was based on considera- 

 tions of patterns of flow, bottom temperatures, a volume transport 

 balance, temperature-salinity correlations, and a deep water isentropic 

 analysis. Using the Meteor results, Hidaka ^ computed the depth of 

 the motionless surface in the Atlantic from 20° N. to 30° S., assuming 



3 Haurwitz, B., and H. A. Panofski "Stability and Meandering of the Gulf Stream" Trans. Amer. 

 Geophys. Union, vol. .31, No. 5, pi). 72.S-731 (October 1950) Washington. 



* Soule, Floyd M., "Consideration of the depth of the motionless surface near the Grand Banks of New- 

 foundland, " Jl. Marine Res. vol. II, No. 3, pp. 169-180 (January 1940), New Haven. 



5 Hidaka, Koji, "Depth of motionless layer as inferred from the distribution of salinity in the ocean." 

 Trans. Amer. Geophys. Union vol. 30, No. 3, pp. 346-348 (June 1949), Washington. 



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