Operational requirements permitting, d3^namic topographic sur- 

 veys have been made so as to include the reoccupation of certain 

 sections across the Labrador Current from South Wolf Island, Lab- 

 rador, to the southern slope of the Grand Banks. For each such 

 occupation the temperature and velocity structure of the Labrador 

 Current have been examined and the volume transport, mean tem- 

 perature, minimum observed temperature, and heat transport have 

 been recorded. As the data have accumulated, estimates of tentative 

 normal seasonal variation relationships have been made and published 

 from time to time. The location of these sections, their designations 

 and the most recently published tentative normals can be found in 

 Bulletin No. 48 of this series. 



The term "heat transport" as used by the CG Oceanographic Unit 

 is the product of in-situ temperature and volume transport obtained 

 from the summation of products of elemental graphically determined 

 areas of cross section enclosed between two isotherms and two lines 

 of equal velocity multiplied by the average velocity in the enclosed 

 area and by the average temperature in the enclosed area. The 

 first two factors give an elemental volume transport and their summa- 

 tion gives a figure for the volume transport across the section. For 

 the measurement of small areas, a figure for the mean temperature is 

 obtained by dividing the summation of area times velocity times 

 temperature by the summation of area times velocit\^ in an effort 

 to reduce planimeter errors. The figure for mean temperature thus 

 obtained is then used to multiply the best value of volume transport 

 to obtain the heat transport. 



A summary of the results of the analyses of the data obtained 

 from the 1963 season and postseason reoccupation of sections across 

 the Labrador Current for which tentative seasonal normals have 

 been published is found in table VIII, and the volume transports 

 have been shown schematically in figure 31. Volume transports 

 are given in millions of cubic meters per second, mean, and minimum 

 observed temperatures in degrees C, and heat transport in millions 

 of cubic meter degrees C. per second. 



Sections T, U, and W, located south of the latitude of Flemish 

 Cap, showed a characteristic volume transport decrease as the season 

 advanced, with sections U and W above normal for the entire season 



59 



