Jökull - 01.12.1979, Page 78

Fig. 2. Distribution of
precipitation. Average for
1931 —1960. From
Eythorsson and Sigtryggs-
son, 1971.
down to the ablation areas where the ablation is
extremely high. Up to 10 m of ice is melted per year
at the snouts terminating at an elevation of about
100 m. Typically the accumulation area is 1.7 times
larger than the ablation area. Very high surface
velocities have been observed. Velocities of over 1
m/day are common. At Hoffellsjökull in 1937
velocities up to 2.1 m/day were reported. The
present surface velocity of Skeidarárjökull is on the
average 1.2 m/day where the glacier flows in a 8.6
km wide channel out from the plateau towards
Skeidarársandur (Fig. 3).
Fig. 3. ERTS-1 image of
Vatnajökull and the
southern coast of Iceland.
Key: 1: Skeidarársandur,
2: Skeidarárjökull, 3:
Grímsvötn, 4: Grænalón,
5: Breidamerkursandur, 6:
Breidamerkurjökull, 7:
Tungnárjökull, 8: Bárdar-
bunga, 9: Kverkfjöll, 10:
Esjufjöll.
76 JÖKULL 29. ÁR