1906. No. 3: AMUNDSEN’S OCEANOGRAPHIC OBSERVATIONS IN 1901. Th 
intermediate warm layer had a temperature about ı'ı8°C. at 300 and 
350 metres}. 
It was already mentioned above that whereever the sea is covered 
with a toplayer of comparatively light Polar water, with low temperature 
and low salinity, there must be also expected an intermediate layer of 
warmer water with higher salinity between the light top layer and the 
heavy bottom-water; and simply because this warmer water has a den- 
sity between that of the top layer and that of the bottom-water. From 
the adjacent warmer parts of the ocean it will therefore everywhere find 
its way in between the two colder waters. This characteristic feature is 
therefore found in the North Polar Basin, in the northern parts of the 
Barents Sea, in the East Greenland Polar Current, in the Baffin Bay, 
and also in the Antarctic Sea. 
At most of Amundsen’s Stations it is not found, because there is 
no top-layer of the typical light cold polar water, and because the 
sinking of the heavy surface water has given no room for this warmer 
intermediate water; but it is possible that it might appear, to some 
extent, later in the season when the heavy water has sunk to lower 
levels. 
Melting of Ice due to underlying Warmer Water. 
Prof. Otto Petterson and Hj. Ostergren believe that it is the 
assumed warm undercurrent North of Jan Mayen which keeps the way 
open to the east coast of Greenland almost every summer?, and Petter- 
son also believes that these currents underlying the cold water, are on 
the whole of much importance in the melting of the ice of the Polar 
seas. Precisely how the authors think that this undercurrent could 
manage to keep the way open, does not, however, seem to be quite 
clear; is it by altering the direction of the surface current, or by melting 
the ice on the surface? The latter is impossible, simply because the 
warm undercurrent is separated from the overlying ice by a layer of 
1 Prof. Pettersson mentions as evidence going to show that the underlying varm water 
of the East Greenland Polar Current cannot come from the north, that Dr. Akerblom 
found it to contain a very high percentage of oxygen (32°04 °/,). He believes that, if 
this under current had made “the grand circuit along Spitsbergen etc.” its contents of 
oxygen ought to have been far more reduced. He seems to forget, however, that 
under the Polar Current covered by ice there is very little animal life to reduce the 
oxygen, and it must therefore be expected that even in the North Polar Basin the 
underlying warm water will always have a comparatively high percentage of oxygen. 
2 Op. cit. Ymer, vol. XX, 1900, Stockholm, p. 327. 
