PHYSICAL OCEANOGRAPHY OF THE GULF OF MAINE 
727 
Changes in the salinity of the surface water off the western coast of Nova Scotia 
from March to April, or to the southward of Cape Sable, demand attention, because 
any considerable movement of the cold, comparatively fresh water of the Nova 
Scotian current past Cape Sable from the eastward would necessarily decrease the 
salinity of the neighboring parts of the Gulf of Maine, just as it retards the warming 
of the surface there (p. 558). In 1920 no evidence of this appears in the distribution 
of salinity up to the end of April. In fact, the surface was actually slightly salter on 
Browns Bank, near Seal Island, and off Yarmouth, Nova Scotia, on April 13 to 16 
(stations 20102, 20104, and 20106) than it had been on March 13 to 23 (stations 20072, 
20084, and 20085), and with no appreciable change in the Northern Channel. 86 
Stations 
Fig. 103. — Salinity profile running eastward from Cape Cod, March 28 to 29, 1919 (ice patrol stations 1 to 3) 
In 1919, however, the very low temperature recorded in the eastern side of the 
basin by the Ice Patrol cutter on March 29 (p. 553) had its counterpart in surface 
salinity considerably lower (31.87 per mille) than that of the western side of the gulf 
at the time (32.4 to 32.7 per mille; fig. 103). Judging from the geographic location, 
this can hardly have drawn from any source other than the Nova Scotian current. 
Unfortunately no observations were made on the salinity of the northern parts of 
the gulf during the spring of 1919, so that it is impossible to state how much this 
Nova Scotian water had affected the surface salinity in that direction, nor (for the 
same reason) how far it spread over the offshore banks to the southwest during 
that spring. Probably, however, it reached its farthest westward expansion by the 
last of that March or soon after, because a second profile of the gulf crossed the 
isohaline for 32 per mille at about the same longitude a month later (Ice Patrol sta- 
tions 19 to 22, p. 997) . A considerable amount of water of low salinity must therefore 
18 No observations were taken in the gulf during the summer of 1920. 
