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Figure 11.10-year overlapp-
ing means of annual temper-
ature, 1901 -1990 in Grímsey
and Angmagssalik, 1922-90
inJanMayenand 1925-90 in
Scoresbysund/Kap Tobin.
— 10 ára raðmeðaltöl árs-
hita, 1901-1990 í Gríms-
ey og Angmagssalik, 1922-
1990 á Jan Mayen og 1925-
1990 á Scoresbysund/Kap
Tobin.
As already mentioned, the variation of 10-year
overlapping means, is much larger in Hopen, Björnöya
and Isfjord radio than in the Icelandic weather stations
(Grímsey, Teigarhorn). However, two characteristic
changes of temperature are very similar, i.e. the sudden
warming starting around 1920, and the cold period,
1965-1971, starting however 1952/61 in the northern
region and reaching a minimum in 1962/71. These
characteristics are seen in Grímsey and Teigarhorn.
Further, a distinct difference between the Icelandic and
the northerly stations can be pointed out, e.g. the cold
period 1940-1943 (Figure 8) is not seen in Grímsey
and Teigarhorn. On the other hand the years 1943 and
1944 are generally rather cool in Iceland.
Figure 10 shows a mean deviation of annual tem-
perature in the period 1901-1925 compared to the pe-
riod of 1925-1990. The values are calculated using
the standard deviation of 1925-1990 as a unit. It is
not possible to calculate the deviation for the north-
ernmost stations, as their observations began in 1912
in Isfjord radio, 1920 in Björnöya and 1946 at Hopen.
Negative deviations, -1.0 to -1.5 cover a rather large
region surrounding Iceland. The lowest deviation is
-0.3 at Tromsö.
We can conclude that, some of the largest varia-
tions of temperature during this century were felt in
Iceland as well as in the northern region. This ap-
plies primarily to two cold periods, the cold one at the
beginning of the century and the period 1962-1971
(1965-1971 in Iceland). The cold period 1940-1943
was not felt in Iceland (Figure 8).
III. Jan Mayen 1922-1990, Scoresbysund/Kap Tobin
1925-1990, Angmagssalik 1901-1990
Figure 11 shows overlapping means of annual tem-
perature for the three above weather stations and the
Icelandic station Grímsey. The variations observed at
the stations north of Iceland are rather like those of
Grímsey. A similar correspondence is noted between
records from these stations and the more northerly
stations (Björnöyaand others), which were compared
with the Icelandic stations in section II.
The cold period 1965-1971, seen in Grímsey,
seems to be more distinct in the northernmost sta-
tions (Björnöya, Hopen, Isfjord radio), than at the sta-
tions closer to Grímsey (i.e. Jan Mayen, Angmagssa-
lik, Scoresbysund/Kap Tobin).
Figure 12 shows the mean deviation of the annual
temperatures of 1965-1971 from those of 1925-1990,
i.e. using the standard deviation of 1925-1990 as a
norm. The regions from the NE coast of Iceland to-
wards Jan Mayen and Denmark Strait from Vestfirðir
8 JÖKULL, No. 43, 1993