82 MARION AND GENERAL GREENE EXPEDITIONS 



topographic map of the Labrador Sea (fig. 122, p. 167) these several 

 tortuous streams are traced to the West Greenland Current, which, as 

 emphasized in chapter IV, branched westward toward the American 

 shore, the bulk of the West Greenland contribution in 1928, as 

 indicated on figure 47, met the American slope between latitudes 68° 

 and 65°, where the Corolian force steepened the dynamic gradient 

 and accelerated the slope current. One of the most important 

 branches of the West Greenland Current, described on page 33, as 

 parting from the slope off Godthaab, is the same as that shown on 

 figure 47, as joining the Baffin Land Current on the Baffin Land 

 slope, in the vicinity of latitude 64°. Although relic traces of 

 Irminger-Atlantic water were found as far north as 65° 37' (p. 42), 

 they apparently formed no continuous current and, therefore, the 

 more southern position is held to have marked in 1928 the source 

 region of the Labrador Current. The point of junction of the Baffin 

 Land Current and the West Greenland Current is probably subject to 

 considerable fluctuation along the Baffin Land slope from the Davis 

 Strait Ridge southward. The physical character and the distribu- 

 tion of velocity of the currents before and after forming the Labra- 

 dor Current are discussed further in vertical cross section, on 

 page 83. 



The farthest offshore observations, which are located in the lower 

 right-hand part of figure 47, indicate the presence of a northerly 

 countercurrent. Had the 1928 survey been extended a little farther 

 offshore in this region, more definite statements regarding the circu- 

 lation there could be made. In the light of subsequent Coast Guard 

 observations (p. 170) it can be stated, however, that in 1928 outer por- 

 tions of the Labrador Current in the vicinity of latitude 53°, longi- 

 tude 50°, joined in an easterly set with a branch of the Atlantic 

 Current. 



Two areas marking weak currents are noted near Hudson Strait 

 on figure 47, the one due east of the strait and the other extended 

 for about 150 miles southward of Hudson Strait along the coast. In 

 the first case the continuation of the Hudson Strait trough across 

 the continental shelf forms an embayment of deeper water around 

 which, in 1928, the currents were turned c^yclonically. The free 

 area along the coast south of Hudson Strait is also attributed 

 to the shelf contour; the bottom being flat and near the surface 

 caused the more rapid currents to sweep out around the steepest 

 inclination of the slope. 



A third region of w^eak circulation was located over a broad de- 

 pression in the continental shelf southeast of Belle Isle, around which 

 a cyclonic eddy w^as developed. 



An interesting feature of the Labrador Current in 1928 Avas the 

 apparent tendency as revealed by the streamlines (fig. 47) to group 

 themselves in two bands — the one over the inshore portion of the 

 continental shelf and the other over the steepest part of the slope. 

 The banding may have been due to (a) the bottom configuration, one 

 of the chief features of the Labrador shelf being a series of longi- 

 tudinal folds which are to be seen in many of the cross sections (figs. 

 48, 50 and 51) ; or (h) the separate sources of the Labrador Current; 

 or (c) a combination of (a) and (h). The Baffin Land Current as 

 described (p. 68) was a relatively shallow, frigid stream which, hold- 



