In considering- the meaning of the net transport in the past a 

 net southeasterly flow has been taken to mean the excess of con- 

 tributions into Baffin Bay through the northern openings (Smith 

 Sound, Lancaster Sound, Jones Sound), over the amounts which 

 sank below the reference surface in the Labrador Sea to exit to 

 the Atlantic below the reference surface. When the net transport 

 was northwesterly the balance was again presumed to be accom- 

 plished by sinking past the reference surface between the section 

 and Davis Strait with a resulting net outflow below the reference 

 surface. While it is realized that the cumulative errors of the 

 second depth integral which are involved in the transport com- 

 putation make the computed net transport below the reference 

 surface of doubtful accuracy, if the northwesterly direction is 

 significant it requires some revision in our thinking regarding 

 the movement of the deep water of the Labrador Sea. 



The tendency of the deeper isentropic surfaces in the Labrador 

 Sea to parallel the bottom, resulting in an inclination upward 

 toward Davis Strait ridge provides the possibility for water to 

 change depth with the performance of a minimum of work. Thus 

 it seems probable that the transfer of water across Davis Strait 

 ridge is not always from north to south and that the oxygen-poor 

 water in the deeper waters of Baffin Bay are kept from complete 

 depletion of oxygen not only by water sinking from high levels 

 within Baffin Bay itself but also by water crossing the threshold 

 of Davis Strait from the south. Similar considerations suggest 

 that the contributions of the Labrador Sea to the deep and bottom 

 water of the North Atlantic may not be an annual cycle but may 

 involve irregular periods with no contributions in one or more 

 succeeding winters. The system cannot be clearly defined until 

 such time as more extensive and repeated observations are avail- 

 able from both the Labrador Sea and Baffin Bay. 



SUMMARY 



1. Three dynamic topographic charts resulting from as many 

 surveys of the Grand Banks region made in 1958 have been 

 presented. 



2. The Effects of the abnormal amount of onshore winds along 

 the Labrador coast in the first 3 months of 1958 is altering the 

 thermo-haline structure of the Labrador Current have been 

 discussed. 



3. The temperature-salinity characteristics of the three water 

 masses found in the Grand Banks in 1958 have been compared 

 with mean values 1948-58. 



4. An extra southerly extension of a section southward from 

 the Grand Banks completely crossing the Atlantic Current and 



61 



