THE GULF STREAM 



Nova Scotia by 35 centimeters. There is a discrepancy between 

 the results of precise leveling and "oceanographic leveling" based 

 on the current and mass distribution: The piling up of water 

 along the coast takes place in the shallow coastal water only and 

 does not extend beyond the continental slope. At the edge of the 

 shelf the level sinks to the value suggested by the oceanographic 

 data, and consequently a current flows to the south along the con- 

 tinental slope, following the contour lines. This current, flowing 

 in the opposite direction to the Gulf Stream, lies between it and 

 the coast. At the tail of the Grand Banks the Gulf Stream comes 

 into close propinquity with the Labrador current, which flows 

 south past Newfoundland and on to the banks. The warm mois- 

 ture-laden air from over the Gulf Stream is chilled as it passes 

 over the cold surface water of the Labrador current, thereby pro- 

 ducing the abundance of fog for which the region is noted. 



As to the internal structure of the Gulf Stream, the main char- 

 acteristic is that the stream is by no means a surface current, but 



extends to great depths. The speed decreases from the surface 

 downward, but it is still significant at a depth of 1,500 meters 

 (nearly 5,000 feet). The flow of water in the surface layers is 

 only a small part of the total transport of the stream, and this fact 

 modifies the common concepts of the stream which are based on 

 surface phenomena. If we examine a vertical section of the 

 ocean from the eastern end of Long Island to Bermuda, we find 

 that at any level except near the surface, the temperatures rise as 

 ive go across the stream.. Thus at a depth of 500 meters (1,640 

 feet) the temperature rises from 6° to 16° C. This means that 

 the water which is moving rapidly, and which therefore consti- 

 tutes the stream, is on the average colder than the Atlantic water 

 on its right. The oceanographer may be forgiven if he dislikes 

 the popular concept of the Gulf Stream as a river of warm water 

 running through the ocean. 



Copyright Queen's Quarterly J950 

 (Repnnled from Queen's Quarterly, Vol. LVll, No. 1, 1950;. 



80 



tJ. S. GOVERNMENT PRINTING OFFICE : 1967 O - 272-494 



