Jökull - 01.12.1969, Page 6

The Ice in the North Polar Basin and in the Greenland Sea,
and the General Causes of Occasional Approach of the Ice
to the Coast of Iceland
TRAUSTI EINARSSON
DEPARTMENT OF ENGINEERING, AND SCIENCE INSTITUTE,
UNIVERSITY OF ICELAND
The first part of this paper gives an account
of seasonal changes of sea-ice in the Northern
Hemisphere, of types of ice in the Polar Basin
and their drift. To illustrate in a general way
the probable maximum thickness of new ice
formed in the Greenland Sea, it is pointed out
that the conditions here as to degree-days and
salinity are very similar to those in the Baffin
Bay—Davis Sund area. But the strong south-
ward current in the Greenland sea limits the
time of ice growth to about i/3 of that on the
west side of Greenland.
The drift of Papanin’s station and that of
Arlis II is used to find the net velocity of drift
as a function of latitude in the Greenland Sea,
Figs. 1 ancl 2. The ice will drift in about 2
months from the 80th to the 70th parallel and
in about 3 months to Kap Farvel.
The Greenland Ice in October—November is
essentially caused by inflow from the Polar
Basin; the narrowing of the drift down to the
latitude of Northwestern Iceland at that time
(Fig. 3) corresponds mainly to the increase in
velocity of drift. This increase in velocity guar-
antees that all the inflow from the Polar Basin
would pass well north and west of Iceland if
winds and new ice, formed in the Greenland
Sea, did not enter into the picture. But such
Fig. 1. Net monthly drift of Papanin’s sta-
tion and Arlis II: straight lines between the
positions at the beginning ancl end of each
month.
2 JÖKULL 19. ÁR