Jökull - 01.12.1969, Side 16

Fig. 1.
Major drifts of
ice in the Arc-
tic Ocean. The
Pacific Gyral,
the Transpolar
Drift and the
East Greenland
Current.
(K. Striibing,
1968).
assume that the monthly pressure pattern over
tlie EGC to a certain degree is a measure for
the mean wind field. And according to Zubov
(1944) the wind drift of ice is approximately
parallel to the isobars.
For January 1965 (Fig. 2) the mean pressure
pattern indicates wind drift cf ice along the
EGC but away from Iceland. In February the
anticyclone south of Iceland causes a diverg-
ence in the ice drift in the Greenland Sea.
At the encl of February 1965 the ice lies close
up to the north coast and the formation of
an ice tongue along the east coast is in sur-
prisinglv good accordance with what coulcl be
expected from the pressure pattern. In March
1965 northerly wincls dominate together with
a divergence in the pressure field north of Ice-
land and the ice-map illustrates the corre-
12 JÖKULL 19. ÁR
spondingly bad ice conditions. In April and
May 1965 the Icelandic low dominates the
pressure pattern and the ice disappears from
the coast at that time.
The year 1966 seems to be the exceptional
one among these 4 years. Due to a persistency
of the Icelandic low, easterly winds are
dominating ancl no sea-ice comes to the coast.
Pressure patterns and ice conditions should be
compared with those of 1965.
In 1967 the pressure pattern is favourable
until March but then the ice border appro-
aches the northern coast of Iceland. Tliere
seems to be a small cyclonic activity over the
EGC in April, and May is dominated by eastcr-
ly winds. The change in the ice conditions is
in goocl accordance with tlie change in the
pressure pattern.