1 91 5- No. 2. SPITSBERGEN WATERS. 39 



deeper strata of the deep-water, with temperatures below zero, have a 

 slightlv lower salinity than the strata at higher levels, with temperatures 

 above zero. 



We thus see that the salinit\- of the deep-water of the North Polar 

 Basin is exactly the same as that of the deep-water of the Norwegian Sea. 

 It seems then probable that it is the same kind of water that is originally 

 formed during the winter at the surface of the Norwegian Sea in the 

 limited area between Jan Mayen and Spitsbergen, as I have described on 

 a previous occasion [1906, p. 75 ft seq.; see also Helland-Hansen and 

 Nansen 1912]. The fact that the deep water of the North Polar Basin has 

 a higher temperatur — with a minimum of about — 0.8' C. or — 0.9' C — 

 than the deep-water of the Norwegian Sea, where the temperature is about 

 — 1.2= C. or — I.I- C, might be due to its becoming heated (b\- intermixture) 

 in its circulation from the Norwegian Sea northwards into the North Polar 

 Basin. If this explanation were accepted, it would not be necessar\- to 

 assume that there is a continuous submarine ridge between Spitsbergen 

 and the northern part of Greenland, the existense of which I previously 

 thought was proved by the assumed difference of salinity between the 

 deep-water of the North Polar Basin and that of the Norwegian Sea. 



It is, however, possible that the difference of temperature in the two 

 basins might be explained by a low continous ridge between Spitsbergen 

 and Greenland, which prevents the coldest deep-water near the bottom of 

 the Norwegian Sea from running into the North Polar Basin. It would 

 then be only the deep-water at some higher level, where the temperature 

 is higher, that could flow over this ridge and form the deep-water of the 

 North Polar Basin. A submarine ridge rising to levels of between i 500 

 and I 200 metres below the sea-surface, and extending continuously from 

 Spitsbergen to Greenland, might be sufficient to prevent the coldest deep- 

 water of the Norwegian Sea, with temperatures below — 0.9^ C., from 

 running into the North Polar Basin (cf. the Belgica Stations 15 — 18, north- 

 west of Spitsbergen [see Dlx d'Orleans, 1907, PI. LX\'I] ). 



The Deep-Water of the Norwegian Sea. 



At Stations 17 and 57 we collected some samples of the cold deep- 

 water of the Norwegian Sea. At Station 57, cold water was observed at 

 900 metres with a temperature of — 0.84' C. and a salinit}' of 34.896 ° oo- 

 At 700 metres, at the same station, the salinity was 34.91 ° 00. an<^ the 

 temperature was slightly above zero. 



