132 



Due to the pi-oximity of the Newfoundland land area and its con- 

 sequent chilling effect on the bottom \yater, the bottom temperature 

 distribution, as shown by sketch No. 7, does not give us the excellent 

 picture of circulation that is presented in sketches 8, 9, and 10. The 

 bottom salinity distribution, sketch No. 8, shows with the utmost 

 clarity the movement of two distinct water masses at this time south 

 of Newfoundland. The isohalines of relatively salt water project- 

 ing in consecutive tonguelike shapes into the " gulley," southwest- 

 ward of Cape Eace record the movement of Arctic M^ater reaching 

 out as far as the continental edge, at which point it abuts against 

 salty oceanic water. Fresh coastal water is shown in wedgelike form 

 covering the entire bottom of St. Pierre Bank, a movement which 

 proceeded from the north and northwest and which unmistabably 

 flanked any possible arctic invasion to the westward. The surface 

 distribution of salinity and temperature, sketches Nos. 9 and 10, 

 corroborate the evidence presented by the bottom salinities. Surface 

 temperatures, sketch No. 9, portray the movement of the icy polar 

 water which poured southwestward tlirough the " gulley *' and off- 

 shore but no farther than the continental edge. The continued flow 

 of arctic water to the westward was equally effectually blocked by 

 warm fresh surface layers spreading out from the Newfoundland 

 coast. Such a movement, which flooded all depths over St. Pierre 

 Bank, caused a shai-p north-and-south line of demarkation to occur 

 in longitude 55° west, between the Arctic and coastal masses. The 

 patrol has long been of the opinion that little polar water succeeds 

 in penetrating much farther than the continental edge south and 

 west of Cape Eace and the evidence which is presented by sketches 

 7 to 10 conclusively support such a belief. Furthermore they refute, 

 for the period of April 17 to May 5 at least, a popular conception 

 that the Labrador current flows inshore of the Gulf Stream south- 

 ward down the Ignited States coast. 



CIRCULATION VICINITY TAIL OF GRAND BANK 



Sketches 11 and 12 sliow the distribution of salinity and tempera- 

 ture at a depth of 50 meters (27 fathoms) around the southern part 

 of the Grand Bank and along its eastern side April 24 to May 10. 

 In general they i)icture a distribution similar to that shown on 

 sketch No. 6, except to record a change since March in the transfer- 

 lence of arctic water along the eastern slope. A movement of warm 

 salty Atlantic water inshore toward the southwest slope also took 

 place. The foregoing appears to establish one fact in particular, 

 namely, that in general the distribution of Arctic, Atlantic, and 

 lianks water maintains more or less the same relationship over ex- 

 tended periods. In fact the conditions as pictured by sketches 11 



I 



