the uniformity found below those hiyers. Thus water of varying pro- 

 portions of the parent water masses Avas found at some stations down 

 to depths of as much as 200 meters, ahhough at most stations the 

 water approached the characteristics of one of the tliree T-S rela- 

 tionships at depths greater than 70 meters. 



From figure 17 it will be seen that down to depths of about 400 

 meters the Labrador Current water and the mixed water followed 

 much the same characteristic curve as was found for the earlier 8-year 

 mean. These two water masses at the deeper depths, and the Atlantic 

 Current water at all depths, were colder and fresher than the 8-year 

 mean. However, since the dift'erences from the mean temperatures 

 and salinities for the 8-year period oppose each other in affecting 

 the density, changes in a^ were small and, for the levels of GOO, 800, 

 and 1,000 meters were respectively +0,01, —0.02 and —0.02. 



To facilitate comparisons of conditions found during different sur- 

 veys and during different years, certain sections designated T, U, 

 and W have been repeated whenever a survey could be accommodated 

 to permit their occupation. They are located as follows: T running 

 southeasterly from about 40°20' X., 41)°00' W. ; U extending east and 

 west at about the 45th parallel ; and W running southerly oft' the Grand 

 Banks at about the 50th meridian. 



The earlier observations (dating from 1934) probably have not 

 been Avell enough distributed in point of time so that their average 

 values may be taken as normals, but until other data are available 

 these averages are the best basis for comparison that we have and 

 are made use of here. In the following it will be understood that 

 volumes of flow are given in units of 1 million cubic meters per 

 second and temperatures expressed in ° C. With respect to normals 

 and time of year, the April survey showed the Labrador Current 

 passing section T to have a volume of 3.40 (0.53 below normal) and 

 a mean temperature of 1.55 (0.59 beloAv normal). At section U, the 

 volume of flow was 2.87 (2.97 below normal), and the mean tempera- 

 ture was 2.85 (0.81 above normal). At section ~\V, the volume was 

 2.83 (1.04 below normal), and the n^iean temperature was 2.43 (0.03 

 below normal). During the May survey, the volumes of flow past 

 sections T, U, and W were respectively 1.67 (1.88 below normal), 

 3.51 (1.95 below normal), and 2.19 (1.42 below normal), with cor- 

 responding mean temperatures of 1.70 (0.44 below normal), 1.75 (0.39 

 below normal), and 4.58 (1.9G above normal). 



Thus the volume of flow was below normal at each section at each 

 survey and except for section U during the April survey and section 

 ^Y during the May survey, the mean temperature was also below 

 normal. As the Labrador Current is formed by tlie junction of the 

 Baffin Land Current and that part of the relatively Avarm West 

 Greenland Current, Avhich branches westward south of Davis Strait, 



64 



