1906. No. 3. AMUNDSEN’S OCEANOGRAPHIC OBSERVATIONS IN 1901. 23 
heat during the winter. The vertical circulation thus produced reaches 
‘the bottom in all parts of the sea, where the horizontal circulation is not 
too rapid, especially in the shallower waters over the banks (as is beau- 
tifully demonstrated by Amundsen’s Stat. 6), but also, as will be mentioned 
below, in the northern central part of the central hollow or basin of the 
eastern Barents Sea. As pointed out in the above mentioned memoirt it 
is “highly probable that the sea-surface in the neighbourhood of the coasts, 
has a considerably higher salinity at the end of the winter than during the 
summer, for the water is then less diluted by the admixture of fresh-water 
from the rivers and the land, and its salinity is on the other hand in- 
creased by the formation of ice on the surface”?. It is thus easy to 
understand how it is, that, in the summer, the cold bottom-waters which 
are remnants of the cold winter-water, have higher salinities than the 
overlying water-strata. The top-layers of the sea are then also much 
diluted by the melting of the ice-masses formed during the winter. As the 
salinity varies much in the different regions of the shallow sea, it may 
also be expected that the salinity of the bottom-water in these same regions 
will vary accordingly. Over the deeper hollows and channels of the sea 
there is more atlantic water with higher salinity, but there is also at the 
same time more horizontal circulation in the various water-strata, and the 
vertical circulation has greater difficulties in reaching to the bottom. The 
very cold bottom-water is, therefore, more easily formed on the shallower 
banks and on the shelves near the coasts. 
The many series of observations now taken, by Knipowitsch, Breit- 
fuss, Wollebæk, Makaroff, and Amundsen, give a fairly clear idea of the 
formation of the cold bottom-water of the Barents Sea, and of its distri- 
bution in the months between spring and autumn. Distinction may per- 
haps, for the sake of clearness, be drawn between four cold bottom-waters, 
formed in four different regions, w/z. 
1) Cold bottom-water with a comparatively low salinity formed on the 
southern bank or shelf, with wery shallow water, north of the Russian 
coast, where the sea-water is much diluted by water from the great 
rivers (typical example is Amundsen’s Stat. 6, see Pl. IV, Sect. II). 
2) Cold bottom-water, often with a remarkably high salinity near 
the bottom, formed on the shelf along the west and southwest coast 
£ Op. cit. p. 280. 
? The same explanation of the origin of the cold bottom-water is also partly accepted by 
Dr. Knipowitsch in his recent paper, loc. cit., 1905. 
