The Botany of Iceland - 01.12.1914, Page 85

PHYSICAL OKOGRAPHY
269
Table I. Mean Temperature of the Surface Water of the Ocean round
Iceland for the Period 1872—1906. (Centigrade scale used.)
Name of Statíon January u 0 March April May June July August 0) 0 qT crj October 3 S (U > O £ December > Winter Spring Summer Autumn Averageforyear
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Stykkisholm. . 0.9 0.3 0.4 1.7 4.7 8.2 10.4 10.6 9.1 6.3 3.7 1.8 1.0 2.3 9.7 6.4 4.9
The Vest- mannaeyjar. 4.1 4.1 4.5 6.1 7.7 9.5 10.9 10.8 9.1 6.8 5.1 4.1 4.1 6.1 10.4 7.0 6.9
Papey 0.7 0.4 0.5 1.5 3.1 4.8 6.0 6.6 6.2 4.3 2.6 1.3 0.8 1.7 5.8 4.4 3.2
Grímsey 1.8 1.4 0.7 1.3 2.6 4.2 6.6 7.4 6.9 5.3 4.1 2.9 2.0 1.5 6.1 5.4 3.8
The temperature-conditions of the coastal districts correspond
very closely with those of the ocean. The north-east coast has, on
an average, a mean winter-temperature of from —2° to —4° (2,
a sunnner temperature of 6° to ll!‘i0 C., and a mean 1‘or the
tvhole year of 1° to 2°C.; while the south-west coast has a winter
temperature ol’ 0° to — 2° C., a summer temperature of 9° to 10° C.,
and one l'or the whole year of 3° to 4°. When the Greenland drift-
ice blockades the coast, the difference hetween these temperatures
is considerably greater. In the severe ice-year, 1881, the difference
between the temperature on the isle of Grímsey and in the Vest-
mannaeyjar, from January to March, was IOV20 to 14° C., while
normally in these inonths it is only 3V20 to 5V20; in the same
months (in 1881) the difference of temperature between Stykkisholm
and the Vestmannaeyjar was 7° to 10° C., while normally it is only
3° to 4°. Therefore the temperature varies very greatly from year
to year, and so also does the mean of the different months. For
instance, take the month of March: at Stykkisholm the highest
mean temperature in a period of 33 years was 2.9° C.; and the
lowest meau in tlie same period was —13.3° C. From this it will
be seen that the Polar current, and especially the drift-ice, exercises
a great iníluence upon the climate in Iceland and thereby upon
the vegetation and the means of sustenance of the people. When
the Polar ice arrives at the north coast the temperature immediately
falls: when in May and June the people who live in South Iceland,
see that it is snowing on the mountains, they at once take it as a
sign thal the dreaded drift-ice is atiout to blockade the coast ol.
18*