Greinar (Vísindafélag Íslendinga) - 01.01.1935, Side 92

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relative positions of land and sea, as the fossiliferous
stratum at Gelgjutangi, dating from this interglacial
period, is only a few metres above sea-level, and can-
not therefore have been raised more than a very few
metres. On the other hand the marine layers at Foss-
vogur seem to exclude any noteworthy subsidence of
the land. But off the east and south-east coasts of Ice-
land, where the land-bridge is presumed to have been
there were not, so far as is known, any volcanic erup-
tions during this period; yet the land-bridge theory de-
mands that there should have been a sinking of the
land to the extent of several hundred metres. This
seems improbable to me, and I consider that the sup-
posed land-bridge, if existing at all at some former
period, had been sunk under the sea before the last
interglacial period.
Dr. Lindroth also builds his theory on the assump-
tion that the temperature in the last glacial period was
only 3° C. lower than it is in Iceland now. But although
in the last ice-age the average temperature in some
parts of Europe was only 3 ° C. lower than at present
yet in other countries it is considered to have been still
lower, or 5—6° C., and as the climate is now compara-
tively mild in Iceland considering the latitude, we may
expect that there is a considerable difference between
the climate of the present time and that of the ice-
age. Observations on local conditions lead one to the
same conclusions. The precipitation in the south of
Iceland is great, something like 3000 mm on the
glaciers, and most during the coldest time of the
year. It is therefore unlikely that the increase of the
ice-cap in the glacial period was due to any consider-
able extent to changes in the precipitation. The glaciers
of this period owed their origin almost entirely to the
colder climate. On the other hand the striations near
Reykjavík show that the glacier was rather thick, and
considering how flat the land is there it appears prob-
able that the climate at Reykjavík in this glacial period