Jökull - 01.12.1971, Blaðsíða 6

3 there have, however, been considerable varia-
tions in the mass balance during the past few
decades, but the glacier response to these
fluctuations has not managed to hinder the
general recession. For the last few years the
recession is definitely retarded and if the trend
of cooler summers since 1940 continues, the
effect of variations in the winter precipitation
on the recession will be an interesting study.
A general insight into the climatic condi-
tions in the area during the two glaciological
years 1966—1967 and 1967—1968 may be at-
tained by reference to obervations at the per-
manent weather station at Akureyri 15 km
northeast of Bægisárjökull. A summary of
climatological data from Akureyri is given in
Table 1 and Fig. 3 and Fig. 4 (Vedráttan 1924—
1971). An examination of these data indicates
that the winter precipitation in the former
glaciological year was clearly below normal,
whereas the following summer was very cold.
In the second glaciological year the winter
precipitation on the other hand was at or
above normal but the summer was warmer
than in the year before. Compared with the
“normal period” 1931—1960 both summers
must however be characterized as cold but
rather sunny. Especially the springs and early
summers were cold but the autumns were rela-
tively warm. Except for June in both years
the duration of bright sunshine at Akureyri
4 JÖKULL 21. ÁR
Fig. 3.
a) Mean air temperature
(May—September)
at Akureyri.
b) Precipitation (Septem-
ber—May) at Akureyri.
The broken line indicates 5-
years moving average.
3. mynd.
a) Meðalhitastig sumar-
mánaða (maí—sept.)
á Akureyri.
b) Heildarúrkoma vetrar-
mánaða (sept.—maí) á
Akureyri.
Brotalínan sýnir keðjubund-
in meðaltöl 5 ára.
Fig. 4. A summary of winter precipitation and
summer air temperature at Akureyri.
4. mynd. Vetrarúrkoma og surnarhiti á Akur-
eyri.
was above the average for the period 1931—
1960. The mean air temperature was below
normal except for July of 1968 and Septem-
ber in both years. May 1967 was tlie coldest
one since 1949 and July the same year, which
was quite dominated by northerly winds, was
the coldest since 1915.
Observations carried out on the glacier cover-