Jökull - 01.12.1993, Page 12

Figure 13. 10-year over-
lapping means of annual
temperature, 1901-1990 in
Reykjavík, Grímsey, Godt-
haab/Nuuk and Jakobshavn,
1901-1960 in Ivigtut, 1901-
1980inUpernavik. — lOára
raðmeðaltöl árshita, 1901-
1990 í Reykjavík, Grímsey,
Godthaab/Nuuk og Jakobs-
havn, 1901-1960 ílvigtut, en
1901-1980 í Upernavik.
tions. The northern stations, Jakobshavn and Uper-
navik, show larger variations, starting with a cold
period in the beginning of the century and then an
increasing temperature with similar trend.
Summary ofresults:
The main results of the comparison of the 10-year
overlapping annual mean temperatures are:
The cold period in the first two decades of the cen-
tury appears in all parts of the North-Atlantic region.
The coldest area seems to be in northwestem Green-
land (Jakobshavn, Upernavik) and is clearly also seen
in Isfjord radio.
In Thorshavn and some weather stations at the
coast of W-Norway, temperatures were mild for the
first decades and increased then gradually up to
1930/39.
In Iceland theperiod 1965-1971 was severely cold,
with frequent sea ice along the northern coast. Most
of the North-Atlantic region had a cool or cold period
at the same time. In W-Greenland (Godthaab/Nuuk,
Jakobshavn, Upernavik) the cold weather period came
later than in Iceland, with the lowest values in 1967/76.
The N-Atlantic cooling seems to have started
one year later in Iceland, i.e. 1952/61 in Scores-
bysund/Kap Tobin and Angmagssalik, compared to
1953/62 in Grímsey and at Teigarhorn. This also ap-
pliesto JanMayen. The minimum occurred in 1965/74
in Angmagssalik, 1964/73 in Jan Mayen and 1962/71
in Scoresbysund/Kap Tobin, which coincides with the
minimum in Grímsey and Teigarhorn.
The northernmost stations of the Norwegian Sea
(Björnöya, Isfjord radio, Hopen) have similar charac-
teristics as Scoresbysund/Kap Tobin and Angmagssa-
lik as concerns the start of cooling, and similar to
Grímsey and Teigarhorn concerning the period of low-
est temperatures.
In Thorshavn the temperature decreased during
1960/69, but without a further clear cooling trend.
This is to some extent characteristic for the weather
stations of W-Norway. In the southernmost part of
the study area the cooling is hardly seen, and it is re-
ally not until 1962/71 that gradual cooling took place
in Tromsö and Vardö.
CORRELATION OF ANNUAL TEMP-
ERATURES 1925-1990 BETWEEN ICE-
LANDIC AND OTHER NORTH-ATLAN-
TIC WEATHER STATIONS
In the former sections relationships have been de-
scribed for temperature conditions in Icelandic and
North-Atlantic weather stations, based on extreme val-
10 JÖKULL,No. 43, 1993