PHYSICAL OCBANOGEAPHY OF THE GULF OF MAINE 



535 



Only one other feature of this end of the profile calls for attention — the encroach- 

 ment of water warmer than 7° on the southern side of Georges Bank and the abrupt 

 transition in bottom temperature across the latter from north to south (4° to 12°). 

 The inner parts of the gulf at the coldest season are warmest (5° to 6°) at the 

 bottom, coldest (2°) along shore and within 10 to 20 meters of the surface. 



Fig. 13.— Temperature at a depth of 100 meters, rebuary-March, 1920 



The wedge-shaped contour of this coldest water (3°), projecting shelfiike over 

 the basin, with slightly higher temperatures above it as well as below (fig. 15), taken 

 by itself might suggest some overflow by warmer surface water from the south. 

 The vertical uniformity of salinity in the upper stratum (p. 705), however, favors 



