OCEANOGRAPHY OF SEA OF GREENLAND—DAMAS, 879 
1,000. ‘They are then at the same time very cold and relatively salt. 
It should be noted also that their density is 1.02811. These waters 
can not then be polar waters, properly called. 
According to Nansen and Helland-Hansen, they owe their origin 
to the progressive cooling of the intermediary bed (of Atlantic 
origin, therefore salt). In winter, in the central part of the Green- 
land Sea and during the formation of the bay ice, the water becomes 
cooled at the surface to the freezing point (—1° to —1.8°). At this 
point it becomes more and more dense, sinks into the depths and 
becomes the bottom water (“Veau de fond”). At the time of the 
melting of the ice in summer the surface waters are slowly warmed 
up and there is formed at 
the same time a superficial 
layer of water only slightly 
salt, which impedes the 
penetration of heat into the 
depths. In the center of 
the Sea of Greenland there 
is found, even in summer, a 
great uniformity in the dis- 
tribution of temperatures. 
This is made very clear in 
figures 4 and 5. The for- 
mation of the bottom water 
in the central region of the 
Greenland Sea is then in 
close relation with that of 
the bay ice. This could not 
freeze in situ unless the 
total body of the sea water cfg See Salinity 
had a low temperature. elow aoa D es === above 
The extension of the polar ere 34 ~ 35% 35%o 
ice is likewise in relation Fic. 6.—Temperature and salinity of the Atlan- 
with that of the polar cur- tie current off Spitzbergen. 
rent, and it is evident that the topography of the depths exercises a 
preponderating influence as much upon the ice as upon the body of 
water which carries it. 
The polar current which turns toward the south along the western 
border of the Sea of Greenland, and the Gulf Stream, which flows 
toward the north along its eastern margin, cause the formation of 
a cyclonic system peculiar to this basin, the center of which lies in 
the region of the bay ice above the great depths. This movement. 
cyclonic in the periphery, brings about an ascension of the water of 
the depths in the central regions, and the formation of the bay 
