Rit (Vísindafélag Íslendinga) - 01.07.1931, Side 10

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Fig. 3. The mean temperature in Iceland in ]une—Sept.
Temperature. The third map represents the distribution
of the mean temperature in Iceland during the period ]une
lst to Sept. 30th. The readings are reduced to sea level by
adding 0 .7 C for each 100 m. The monthly mean temp-
erature ]une—Sept. at 30 stations in Iceland will be seen
from table II. As no suifable stations for the calculation of
the vertical temperature-gradient exist in this country I have
used the same mean value as adopted for the glacial re-
search work in South Norway. In the Alps the value of the
decrease of temperature pr. 100 m. rise has been found
to lie between 0 .6 and 0 .7 centigrade.
The distribution of the summer temperature also shows the
interesting fact, that the maximal values are found in the
eastern part of the central highland to the north of Vatna-
jökull, and the minimal ones on the eastern coast of the
Westfjord-peninsula or in the very same districts as the re-
spective maximal and minimal heights of the firnlimit.
Both in Norway and in the Alps the mean temperature at
the firnlimit during summer has been found to be about
+ 2 C in most places. A positive deviation from that tem-